UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, DC 20549
Form 10-K
xANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the fiscal year ended December 31, 2016
For the fiscal year ended
December 31, 2019
¨TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
 
For the transition period from ___________________ to __________________
 
Commission File Number1-07978

BLACK HILLS POWER, INC.
BLACK HILLS POWER, INC.
Incorporated inSouth Dakota IRS Identification Number46-0111677
625 Ninth Street,
7001 Mount Rushmore RoadRapid CitySouth Dakota 5770157702
   
Registrant’s telephone number, including area code:(605)721-1700
   
Securities registered pursuant to Section 12(b) of the Act:None
   
Securities registered pursuant to Section 12(g) of the Act:None


Indicate by check mark if the Registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.
Yes    x    No    ¨
Indicate by check mark if the Registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.
YesNo

Indicate by check mark if the Registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act.
Yes

No
Indicate by check mark whether the Registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the Registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.
YesNo
Indicate by check mark whether the Registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the Registrant was required to submit such files).
YesNo

Indicate by check mark if the Registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act.
Yes    x    No    ¨

Indicate by check mark whether the Registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the Registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.
Yes    x    No    ¨

Indicate by check mark whether the Registrant has submitted electronically and posted on its corporate Website, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the Registrant was required to submit and post such files).
Yes    x    No    ¨


Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of Registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K.
This paragraph is not applicable to the Registrant.        x


Indicate by check mark whether the Registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company, (as definedor an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act).Act.
Large accelerated filer    ¨    Accelerated filer    ¨    Non-accelerated filer    x
Large accelerated filerAccelerated filer
Non-accelerated filerSmaller reporting company
Emerging growth company

If an emerging growth company, ¨

Indicateindicate by check mark whetherif the Registrant is a shell company (as defined in Rule 12b-2has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act).Act.    ¨
Yes    ¨    No    x

Indicate by check mark whether the Registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).
YesNo
State the aggregate market value of the voting stock held by non-affiliates of the Registrant.


All outstanding shares are held by the Registrant’s parent company, Black Hills Corporation. Accordingly, the aggregate market value of the voting common stock of the Registrant held by non-affiliates is $0.

Indicate the number of shares outstanding of each of the Registrant’s classes of common stock, as of the latest practicable date.
ClassOutstanding at January 31, 20172020
Common stock, $1.00 par value23,416,396
shares


Reduced Disclosure
The Registrant meets the conditions set forth in General Instruction I (1) (a) and (b) of Form 10-K and is therefore filing this Form 10-K with the reduced disclosure format.











GLOSSARY OF TERMS AND ABBREVIATIONS


The following terms and abbreviations appear in the text of this report and have the definitions described below:
ACAlternating Current
AFUDCAllowance for Funds Used During Construction
AOCIAccumulated Other Comprehensive Income
ASCAccounting Standards Codification
ASUAccounting Standards Update as issued by FASB
Baseload plantA power generation facility used to meet some or all of a given region’s continuous energy demand, producing energy at a constant rate.
Basin ElectricBasin Electric Power Cooperative
BHCBlack Hills Corporation, the Parent of Black Hills Power, Inc.
Black Hills Electric GenerationBlack Hills Electric Generation, LLC, a direct, wholly-owned subsidiary of Black Hills Non-regulated Holdings
Black Hills EnergyThe name used to conduct the business of our utility company as well as our utility affiliatesaffiliates.
Black Hills Energy South Dakota ElectricIncludes Black Hills Power’s operations in South Dakota, Wyoming and Montana
Black Hills Non-regulated HoldingsBHSCBlack Hills Non-regulated Holdings,Service Company, LLC, a direct, wholly-owned subsidiary of BHC
Black Hills PowerBlack Hills Power, Inc., a direct, wholly-owned subsidiary of BHC (doing business as Black Hills Energy South Dakota)
Black Hills Service CompanyBlack Hills Service Company LLC, a direct, wholly-owned subsidiary of BHCEnergy)
Black Hills Utility HoldingsBlack Hills Utility Holdings, Inc. a direct, wholly-owned subsidiary of BHC
(doing business as Black Hills Energy Wyoming ElectricIncludes Cheyenne Lights electric utility operationsEnergy)
CFTCUnited States Commodity Futures Trading Commission
Cheyenne LightCheyenne Light, Fuel and Power Company, a direct, wholly-owned subsidiary of BHC
Cheyenne PrairieCheyenne Prairie Generating Station is a 132 MW natural gas-fired generating facility in Cheyenne, Wyoming, jointly owned by Cheyenne LightWyoming Electric and Black Hills Power.South Dakota Electric. Cheyenne Prairie was placed into commercial operationsservice on October 1, 2014.
City of GilletteThe City of Gillette, Wyoming affiliate of the JPB.
CO2
Common Use System (CUS)
Carbon dioxideThe Common Use System is a joint transmission system we participate in with Basin Electric and Powder River Energy Corporation. The Common Use System provides transmission service over these utilities' combined 230-kilovolt (kV) and limited 69-kV transmission facilities within areas of southwestern South Dakota and northeastern Wyoming.
Cooling degree day (CDD)A cooling degree day is equivalent to each degree that the average of the high and low temperature for a day is above 65 degrees. The warmer the climate, the greater the number of cooling degree days. Cooling degree days are used in the utility industry to measure the relative warmth of weather and to compare relative temperatures between one geographic area and another. Normal degree days are based on the National Weather Service data for selected locations over a 30 year average.locations.
CorriedaleWind project near Cheyenne, Wyoming, that will be 52.5 MW wind farm jointly owned by South Dakota Electric and Wyoming Electric and will serve as the dedicated wind energy supply to the Renewable Ready program.
CPCNCertificate of Public Convenience and Necessity
CPPClean Power Plan
CTCombustion turbine
DCDirect current
DSMDemand Side Management
ECAEnergy Cost Adjustment - adjustments-- adjustment that allowallows us to pass the prudently-incurred cost of fuel, purchased energy and purchased powertransmission related expenses through to customers.
EIAEnvironmental Improvement Adjustment -- annual adjustment mechanism that allows us to recover from customers eligible investments in and expense related to new environmental measures.
EPAUnited States Environmental Protection Agency
FASBFinancial Accounting Standards Board
FDICFederal Depository Insurance Corporation
FERCUnited States Federal Energy Regulatory Commission
FitchFitch Ratings Inc.
GAAPAccounting principles generally accepted in the United States of America
GHGGreenhouse gas


gases
Global SettlementSettlement with a utilities commission where the dollar figurerevenue requirement is agreed upon, but the specific adjustments used by each party to arrive at the figureamount are not specified in public rate ordersorders.
Happy JackHappy Jack Wind Farm, LLC, a subsidiary of Duke Energy Generation Services

Heating degree day (HDD)A heating degree day is equivalent to each degree that the average of the high and the low temperaturestemperature for a day is below 65 degrees. The colder the climate, the greater the number of heating degree days. Heating degree days are used in the utility industry to measure the relative coldness of weather and to compare relative temperatures between one geographic area and another. Normal degree days are based on the National Weather Service data for selected locations over a 30 year average.locations.
Horizon PointBHC Corporate headquarters building in Rapid City, South Dakota, which was completed in 2017.
IRSInternal Revenue Service
JPBConsolidated Wyoming Municipalities Electric Power System Joint Powers Board. The JPB exists for the purpose of, among other things, financing the electrical system of the City of Gillette. The JPB financed the purchase of 23% of the Wygen III power plant for the City of Gillette.
kVKilovolt
LIBORLondon Interbank Offered Rate
MAPPMid-Continent Area Power Pool
MATSUtility Mercury and Air Toxics Rules under the United States EPA National Emissions Standards for Hazardous Air Pollutants from Coal and Oil Fired Electric Utility Steam Generating Units
MDUMontana DakotaMontana-Dakota Utilities CompanyCo., a subsidiary of MDU Resources Group, Inc.
MEANMunicipal Energy Agency of Nebraska
Moody’sMoody’s Investor Services, Inc.
MTPSCMontana Public Service Commission
MWMegawatts
MWhMegawatt-hours
N/ANot Applicable
Native loadEnergy required to serve customers within our service territory
NAVNet Asset Value
NERCNorth American Electric Reliability Corporation
NOLNet operating loss
NOAANational Oceanic and Atmospheric Administration
NOAA Climate Normals
This dataset is produced once every 10 years. This dataset contains daily and monthly normals of temperature, precipitation, snowfall, heating and cooling degree days, frost/freeze dates, and growing degree days calculated from observations at approximately 9,800 stations operated by NOAA’s National Weather Service.

NOx
Nitrogen oxideOxide
OCIOther Comprehensive Income
OPEBOther Post-Employment Benefits
OSHAOccupational Safety and Health Organization
PacifiCorpPacifiCorp, a wholly owned subsidiary of MidAmerican Energy Holdings Company, itself an affiliate of Berkshire Hathaway
ParentBlack Hills Corporation
System Peak System LoadDemandPeak system load representsRepresents the highest point of customerretail usage for a single hour for the system in total. Our system peaks include demand loads for 100% of plants regardless of joint ownership.hour.
PPAPower Purchase Agreement
PRPAPlatte River Power Authority
PSAPower Sales Agreement
SDPUCSouth Dakota Public Utilities Commission
SECUnited States Securities and Exchange Commission
Silver SageSilver Sage Windpower, LLC, a subsidiary of Duke Energy Generation Services
SO2
Sulfur dioxideDioxide
South Dakota ElectricBlack Hills Power, Inc., a direct, wholly-owned subsidiary of Black Hills Corporation, providing electric service to customers in Montana, South Dakota and Wyoming (doing business as Black Hills Energy).
S&PStandard & Poor’s, Rating Servicesa division of The McGraw-Hill Companies, Inc.
Spinning ReserveSPPGeneration capacity that is on-line but unloadedSouthwest Power Pool, Inc. which oversees the bulk electric grid and that can respond within 10 minutes to compensate for generation or transmission outages.


wholesale power market in the central United States
TCJATax Cuts and Jobs Act enacted on December 22, 2017
TCATFATransmission CostFacility Adjustment - adjustments passed through-- annual adjustment mechanism that allows us to the customer based onrecover charges for qualifying new and modified transmission costs that are higher or lower than the costs approved in the rate case.
Thunder CreekThunder Creek Gas Services, LLCfacilities from customers.
WECCWestern Electricity Coordinating Council
WPSCWyoming Public Service Commission
WRDCWyodak Resources Development Corporation, a direct, wholly-owned subsidiary of Black Hills Non-regulated Holdings LLC(doing business as Black Hills Energy)

Wygen III110 MW mine-mouth coal-fired power plant in which South Dakota Electric owns a 52% interest, MDU owns a 25% interest and the City of Gillette owns the remaining 23% interest. BHP operates the plant.
Wyodak PlantWyodak, a 362 MW mine-mouth coal-fired plant in Gillette, Wyoming, is owned 80% by PacifiCorp and 20% by Black Hills Energy South Dakota. OurDakota Electric. The WRDC mine supplies all of the fuel for the plant.
Wyoming ElectricCheyenne Light, Fuel and Power Company, a direct, wholly owned subsidiary of Black Hills Corporations, providing electric service to customers in the Cheyenne, Wyoming area (doing business as Black Hills Energy).


PART I

Forward-Looking Information


This Form 10-K contains forward-looking statements as defined by the SEC. Forward-looking statements are all statements other than statements of historical fact, including without limitation those statements that are identified by the words “anticipates,” “estimates,” “expects,” “intends,” “plans,” “predicts” and similar expressions and include statements concerning plans, objectives, goals, strategies, future events or performance, and underlying assumptions and other statements that are other than statements of historical facts. From time to time, we may publish or otherwise make available forward-looking statements of this nature, including statements contained within Item 7 - Management’s Discussion & Analysis.Analysis of Financial Condition and Results of Operations.


Forward-looking statements involve risks and uncertainties, which could cause actual results or outcomes to differ materially from those expressed. Our expectations, beliefs and projections are expressed in good faith and we believe we have a reasonable basis, including, without limitation, management’s examination of historical operating trends, data contained in our records and other data available from third parties. Nonetheless, our expectations, beliefs or projections may not be achieved or accomplished.


Any forward-looking statement contained in this document speaks only as of the date on which the statement is made and we undertake no obligation to update any forward-looking statement or statements to reflect events or circumstances that occur after the date on which the statement is made or to reflect the occurrence of unanticipated events. New factors emerge from time to time, and it is not possible for management to predict all of the factors, nor can it assess the effect of each factor on our business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in any forward-looking statement. All forward-looking statements, whether written or oral and whether made by or on behalf of us are expressly qualified by the risk factors and cautionary statements in this Form 10-K, including statements contained within Item 1A - Risk Factors.Factors.


PART I

ITEMS 1 and 2.    BUSINESS AND PROPERTIES


GeneralHistory and Organization


Black Hills Power (“South Dakota Electric,” the Company,“Company,” “we,” “us” and “our”) is a regulated electric utility incorporated in South Dakota corporation doing business as Black Hills Energy -Energy. We are a regulated electric utility company headquartered in Rapid City, South Dakota and serving customers in South Dakota, Wyoming and Montana.Dakota. We began providing electric utility service in 1941. We are a wholly-owned subsidiary of the publicly traded Black Hills Corporation (“Parent” or “BHC”). Engaging

Business

We generate, transmit and distribute electricity to approximately 73,000 customers in theMontana, South Dakota and Wyoming. We own 445 MW of generation and 3,819 miles of electric transmission and distribution lines. Our electric generating facilities and power purchase agreements provide for the supply of electricity provides a solid foundation of revenues, earnings and cash flow that support our capital expenditures, dividendsprincipally to our Parent,own distribution systems.

Capacity and Demand. System peak demands for our overall performance and growth.retail customers for each of the last three years are listed below:
 System Peak Demand (in MW)
 2019 2018 2017
 SummerWinter SummerWinter Summer Winter
South Dakota Electric335320 355314 370 310


Regulated Power Plants.As of December 31, 2016,2019, our ownership interests in electric generation plants were as follows:
Unit
Fuel
Type
Location
Ownership
Interest %
Owned Capacity (MW)
Year
Installed
Fuel
Type
Location
Ownership
Interest %
Owned Capacity (MW)
Year
Installed
Wygen III (a)
CoalGillette, WY52%57.22010
Cheyenne Prairie (a)
GasCheyenne, Wyoming58%55.02014
Wygen III (b)
CoalGillette, Wyoming52%57.22010
Neil Simpson IICoalGillette, WY100%90.01995CoalGillette, Wyoming100%90.01995
Wyodak (b)
CoalGillette, WY20%72.41978
Cheyenne Prairie (c)
GasCheyenne, WY58%55.02014
Wyodak Plant (c)
CoalGillette, Wyoming20%72.41978
Neil Simpson CTGasGillette, WY100%40.02000GasGillette, Wyoming100%40.02000
Lange CTGasRapid City, SD100%40.02002GasRapid City, South Dakota100%40.02002
Ben French Diesel #1-5OilRapid City, SD100%10.01965OilRapid City, South Dakota100%10.01965
Ben French CTs #1-4Gas/OilRapid City, SD100%80.01977-1979Gas/OilRapid City, South Dakota100%80.01977-1979
 444.6  444.6 
_______________________
(a)Cheyenne Prairie supports the utility customers of Wyoming Electric and us. The facility includes one simple-cycle, 37 MW combustion turbine that is wholly-owned by Wyoming Electric and one combined-cycle, 95 MW unit that is jointly-owned by Wyoming Electric (40 MW) and South Dakota Electric (55 MW).
(b)We operate Wygen III, a 110 MW mine-mouth coal-fired power plant and own a 52% interest in the facility. MDU owns a 25% interest and the City of Gillette owns the remaining 23% interest. The adjacent WRDC mine furnishes all of the coal fuel supply for the plant.
(b)(c)Wyodak isPlant, a 362 MW mine-mouth coal-fired power plant, is owned 80% by PacifiCorp and 20% by us. This baseload plant is operated by PacifiCorp and WRDC furnishesmine supplies all of the coal fuel supply for 100% of the plant.
Our annual weighted average cost of fuel utilized to generate electricity and the average price paid for purchased power (excluding contracted capacity) per MWh for the years ended December 31 were as follows:
Fuel Source (dollars per MWh)201920182017
Coal$11.48
$11.13
$10.96
    
Natural Gas$17.24
$29.98
$28.46
    
Diesel Oil (a)
$202.08
$268.27
$208.86
    
Total Weighted Average Fuel Cost$13.17
$12.74
$12.41
    
Purchased Power - Coal, Gas and Oil$24.53
$29.01
$28.10
    
Purchased Power - Renewable Sources$46.69
$54.31
$53.08
______________
(c)(a)
Cheyenne Prairie, a gas-fired power generation facility includes one combined-cycle, 95 MWIncluded in the Price per MWh for Diesel Oil are unit thatstart-up costs. The diesel-fueled generating units are generally used as supplemental peaking units and the cost per MWh is jointly owned by Wyoming Electric (40 MW)reflective of how often the units are started and us (55 MW). This facilitywas placed into commercial operations on October 1, 2014.
how long the units run.


Our power supply, by resource as a percent of the total power supply for our energy needs for the years ended December 31 was as follows:
Power Supply201920182017
Coal46%48%47%
Gas and Oil8
4
3
Total Generated54
52
50
Purchased (a)
46
48
50
Total100%100%100%
______________
(a)Wind represents approximately 13%, 7% and 6% of our purchased power in 2019, 2018, and 2017, respectively.



Power Purchase and Power Sales Agreements. We have executed various PPAs to support our capacity and energy needs beyond our regulated power plants’ generation. We also have various long-term PSAs. Key contracts are disclosed in Note 13 and Note 14 of the Notes to the Financial Statements in this Annual Report on Form 10-K.
Distribution
Transmission and TransmissionDistribution. Our distribution and transmission system serves approximately 71,000 electric customers, with anWe own electric transmission system of 1,260 milesand distribution systems composed of high voltage lines (greater than 69 kV) and 2,497 miles of lowerlow voltage lines. In addition, welines (69 kV or less). We also jointly own 44 miles of high voltage linesan electric transmission system, referred to as the Common Use System, with Basin Electric. Our service territory covers areas with a strongElectric and stable economic base including western South Dakota, northeastern Wyoming and southeastern Montana. A majority of our retail electric revenues in 2016 were generated in South Dakota. We are subject to state regulation by the SDPUC, the WPSC and the MTPSC.Powder River Energy Corporation.


The following are characteristics of our distribution and transmission business:

We have a diverse customer and revenue base. Our revenue mix for the year ended At December 31, 2016 was comprised of 36% commercial, 27% residential, 7% contract wholesale, 6% wholesale off-system, 12% industrial2019, we owned the electric transmission and 12% municipal and other revenue.
distribution lines shown below:

We own 35% and Basin Electric owns 65% of a DC transmission tie that interconnects the Western and Eastern transmission grids, which are independently-operated transmission grids serving the Western United States and the Eastern United States, respectively. This transmission tie provides transmission access to both the WECC region in the West and the MAPP region in the East. Our system is located in the WECC region. The total transfer capacity of the tie is 200 MW from West to East and 200 MW from East to West. This transmission tie allows us to buy and sell energy in the Eastern interconnection without having to isolate and physically reconnect load or generation between the two electrical transmission grids. The transmission tie accommodates scheduling transactions in both directions simultaneously. This transfer capability provides additional opportunity to sell our excess generation or to make economic purchases to serve our native load and our contract obligations, and to take advantage of the power price differentials between the two electric grids. Additionally, our system is capable of directly interconnecting up to 80 MW of generation or load to the Eastern transmission grid. Transmission constraints within the MAPP transmission system may limit the amount of capacity that may be directly interconnected to the Eastern system at any given time.

We have firm point-to-point transmission access to deliver up to 50 MW of power on PacifiCorp’s transmission system to wholesale customers in the Western region through 2023.

We have firm network transmission access to deliver power on PacifiCorp’s system to Sheridan, Wyoming to serve our power sales contract with MDU through 2017, with the right to renew pursuant to the terms of PacifiCorp’s transmission tariff.

Power Sales Agreements. We sell a portion of our current load under long-term contracts. Our key contracts include:

MDU owns a 25% interest in Wygen III’s net generating capacity for the life of the plant. During periods of reduced production at Wygen III, or during periods when Wygen III is off-line, we will provide MDU with 25 MW from our other generation facilities or from system purchases with reimbursement of costs by MDU.

We have an agreement through December 31, 2023 under which we serve MDU with capacity and energy up to a maximum of 50 MW.

The City of Gillette owns a 23% ownership interest in Wygen III’s net generating capacity for the life of the plant. During periods of reduced production at Wygen III, or during periods when Wygen III is off-line, we will provide the City of Gillette with its first 23 MW from our other generation facilities or from system purchases with reimbursement of costs by the City of Gillette. Under this agreement we will also provide the City of Gillette their operating component of spinning reserves.

•An agreement under which we supply up to 20 MW of energy and capacity to MEAN under a contract that expires in 2023. This contract is unit-contingent based on the availability of our Neil Simpson II and Wygen III plants with decreasing capacity purchased over the term of the agreement. The unit-contingent capacity amounts from Wygen III and Neil Simpson II are as follows:
 State
Transmission
(in Line Miles)
Distribution
(in Line Miles)
South Dakota ElectricSouth Dakota, Wyoming1,219
2,557
South Dakota Electric - Jointly Owned (a)
South Dakota, Wyoming43

  1,262
2,557
__________________________
2017(a)20 MW - 10 MW contingent
We own 35% of a DC transmission tie that interconnects the Western and Eastern transmission grids, which are independently-operated transmission grids serving the western and eastern United States, respectively. This transmission tie allows us to buy and sell energy in the Eastern grid without having to isolate and physically reconnect load or generation between the two transmission grids, thus enhancing the reliability of our system. It accommodates scheduling transactions in both directions simultaneously, provides additional opportunities to sell excess generation or to make economic purchases to serve our native load and contract obligations, and enables us to take advantage of power price differentials between the two grids. See Note 4 of the Notes to the Financial Statements in this Annual Report on Wygen III and 10 MW contingent on Neil Simpson II
2018-201915 MW - 10 MW contingent on Wygen III and 5 MW contingent on Neil Simpson II
2020-202112 MW - 6 MW contingent on Wygen III and 6 MW contingent on Neil Simpson II
2022-202310 MW - 5 MW contingent on Wygen III and 5 MW contingent on Neil Simpson II.Form 10-K for additional information.


Material contracts are disclosed in Note 13 and Note 14 of the Notes to the Financial Statements in this Annual Report on Form 10-K.



Operating Agreements. Material operating agreements are disclosed in Note 14 of the Notes to the Financial Statements in this Annual Report on Form 10-K. Additional agreements shown below are also key to our operations:
An agreement from January 1, 2017 through December 31, 2021 under which we provide 50 MW of energy to Cargill during heavy and light load timing intervals.

Shared Services Agreements -
Regulated Power Plants and Purchased Power. Our electric load is primarily served by our generating facilities in
South Dakota and Wyoming, which provide approximately 445 MW of generating capacity, with the balance supplied under purchased power and capacity contracts. We generated approximately 57% of our energy requirements in 2016 and purchased approximately 43% which was supplied under the following contracts:

A PPA with PacifiCorp expiring in 2023, whereby we purchase 50 MW of coal-fired baseload power.

A PPA with Wyoming Electric, expiring in 2028, under which we will purchase up to 14.7 MW of wind energy through Wyoming Electric’s agreement with Happy Jack.

A PPA with Wyoming Electric expiring in 2029, under which we will purchase up to 20 MW of wind energy through Wyoming Electric’s agreement with Silver Sage.

A Generation Dispatch Agreement with Wyoming Electric that requires us to purchase all of Wyoming Electric’s excess energy.

Since 1995, we have been a net producer of energy. Our 2016 winter peak system load was 389 MW and our 2016 summer peak system load was 438 MW. None of our generation is restricted by hours of operation, thereby providing us the ability to generate power to meet demand whenever necessary and economically feasible. We have historically optimized the utilization of our power supply resources by selling wholesale power to other utilities and to power marketers in the spot market, and through short-term sales contracts primarily in the WECC and MAPP regions. Our 220 MW of low-cost, coal-fired resources supports most of our native load requirements and positions us for wholesale off-system sales.

Operating Agreements

Related-party Gas Transportation Service Agreement - On October 1, 2014 we entered into a gas transportation service agreement with Wyoming Electric in connection with gas supply for Cheyenne Prairie. The agreement is for a term of 40 years, in which we pay a monthly service and facility fee for firm and interruptible gas transportation.

Shared Services Agreement- We have a shared services agreement with Wyoming Electric, and Black Hills Wyoming are parties to a shared facilities agreement, whereby each entity charges for the use of assets andlocated at the performance of services being usedGillette, Wyoming energy complex by or performed for, anthe affiliate entity. The revenues

South Dakota Electric and expenses associated with these assets are included in rate base.Wyoming Electric receive certain staffing and management services from BHSC for Cheyenne Prairie.


Jointly Owned Facilities - WeSouth Dakota Electric and BHSC are parties to ana shared facilities agreement, withwhereby BHSC is charged for the Cityuse of Gillettethe Horizon Point facility that is owned by South Dakota Electric and MDU for joint ownership of Wygen III. We charge the City of Gillette and MDU for administrative services, plantBHSC provides certain operations and maintenance services at the facility.

Jointly owned facilities agreements are discussed in Note 4 of the Notes to the Financial Statements in this Annual Report on Form 10-K.

Seasonal Variations of Business. We are a seasonal business and weather patterns may impact our operating performance. Demand for their shareelectricity is sensitive to seasonal cooling, heating and industrial load requirements, as well as market price. In particular, demand is often greater in the summer and winter months for cooling and heating, respectively.

Competition. We generally have limited competition for the retail generation and distribution of electricity in our service areas. Various legislative or regulatory restructuring and competitive initiatives have been discussed in the states in which our utilities operate. These initiatives would be aimed at increasing competition or providing for distributed generation. To date, these initiative have not had a material impact on our business.


Rates and Regulation. We are subject to the jurisdiction of the Wygen III generating facilitypublic utilities commissions in the states where we operate and the FERC for certain assets. These commissions oversee services and facilities, rates and charges, accounting, valuation of property, depreciation rates and various other matters. The public utility commissions determine the liferates we are allowed to charge for our utility services. Rate decisions are influenced by many factors, including the cost of providing service, capital expenditures, the plant.



Regulations

Rate Regulation

prudence of costs we incur, views concerning appropriate rates of return, general economic conditions and the political environment. Certain commissions also have jurisdiction over the issuance of debt or securities and the creation of liens on property located in their states to secure bonds or other securities. The following table illustrates certain enacted regulatory information with respect to the states in which we operate:


StateAuthorized Rate of Return on EquityAuthorized Return on Rate BaseAuthorized Capital Structure Debt/EquityEffective DateOther Tariffs, Riders and Rate MattersPercentage of Off-System Sale Profits Shared with Customers
SDGlobal Settlement7.76%Global Settlement10/2014ECA,TCA, Energy Efficiency Cost Recovery/ DSM70%
Jurisdic-tionAuthorized Rate of Return on EquityAuthorized Return on Rate BaseAuthorized Capital Structure Debt/EquityAuthorized Rate Base (in millions)Effective DateAdditional Tariffed MechanismsPercentage of Off-System Sale Profits Shared with Customers
SD 7.76% 6/2011Environmental Improvement Cost Recovery Adjustment TariffN/AGlobal Settlement7.76%Global Settlement$543.910/2014ECA, Energy Efficiency Cost Recovery/DSM, TFA, EIA70%
WY9.9%8.13%46.7%/53.3%10/2014ECA65%9.9%8.13%46.7%/53.3%$46.810/2014ECA65%
MT15.0%11.73%47%/53%1983N/AN/A
FERC10.8%9.10%43%/57%2/2009FERC Transmission TariffN/A10.8%8.76%43%/57%
$138.4 (a)
2/2009FERC Transmission TariffN/A

__________
(a)Includes $121.3 million in 2019 rate base for the Common Use System formula rate that is updated annually and $17.1 million in rate base for the DC transmission tie that is based on the approved stated rate from 2005.

Rates for our retail electric service are subject to regulation by the SDPUC for customers in South Dakota, the WPSC for customers in Wyoming and the MTPSC for customers in Montana. Any changes in retail rates are subject to approval by the respective regulatory body. We have rate adjustment mechanisms in WyomingSouth Dakota and South DakotaWyoming which provide for pass-through of certain costs related to the purchase, production and/or transmission of electricity. We are also subject to the jurisdiction of FERC with respect to accounting practices and wholesale electricity sales. We have been granted market-based rate authority by FERC and are not required to file cost-based tariffs for wholesale electric rates. Rates charged by us for use of our transmission system are subject to regulation by FERC.


A summary of mechanisms we have in place are shown in the table below:
Electric Utility JurisdictionCost Recovery Mechanisms
Environmental CostEnergy EfficiencyTransmission ExpenseFuel CostTransmission CapitalPurchased Power
South Dakota Electric (SD)þþþþþþ
South Dakota Electric (WY)þþþþ
South Dakota Electric (FERC)þ

See Note 7 of the Notes to the Financial Statements in this Annual Report on Form 10-K for information regarding current electric rate activity.

Some of the mechanisms we have in place include:

An approved annual EIA tariff which recovers costs associated with generation plant environmental improvements. We also have a TFA tariff which recovers the costs associated with transmission facility improvements. The EIA and TFA were suspended for a six-year moratorium period effective July 1, 2017. On January 7, 2020, we received approval from the SDPUC on a settlement reached with the SDPUC staff agreeing to extend the six-year moratorium period by an additional three years whereby rate increases for these recovery mechanisms will not go into effect prior to July 1, 2026. See Note 7 of the Notes to the Financial Statements in this Annual Report on Form 10-K for further information.

An approved vegetation management recovery mechanism that allows for recovery of and a return on prudently-incurred vegetation management costs.

In South Dakota we have an annual adjustment clauseECA which provides for the directover or under recovery of increased fuel, transmission and purchased power cost incurred to serve South Dakota customers. Additionally, thethis ECA contains an off-system sales sharing mechanism in which South Dakota customers will receive a credit equal to 100% of off-system power marketing operating income from the first $1.0 million of power marketing margin from short-term sales and a credit equal to 70% of off-system power marketing operating income.margins from short-term sales in excess of the first $1.0 million. We retain the remaining 30%. For the period of July 1, 2017 through March 31, 2023, the 100% credit of power marketing margin increased from $1.0 million to $2.0 million. The modification also adjusts theECA methodology allows us to directly assign renewable resources and firm purchases to the customer load. In Wyoming, has a similar Fuelfuel and Purchased Power Cost Adjustment.purchased power cost adjustment is also in place.

The Common Use System (CUS) has an annual rate determination process that is governed by the FERC formula rate protocols established in the filed FERC joint-access transmission tariff. See Note 7 of the Notes to the Financial Statements in this Annual Report on Form 10-K for further information.

Tariff Filings. See Note 7 of the Notes to the Financial Statements in this Annual Report on Form 10-K for tariff filings and additional information.

Operating Statistics. The following tables provide certain electric utility operating statistics for the years ended December 31:
Heating and Cooling Degree Days
 201920182017
Actual   
Heating degree days8,284
7,749
6,870
Cooling degree days404
488
709
    
Variance from normal   
Heating degree days16 %8 %(4)%
Cooling degree days(36)%(23)%11 %

  Electric Revenue (in thousands) Quantities Sold (MWh)
  201920182017 201920182017
Residential $72,950
$75,319
$72,764
 555,519
546,825
526,730
Commercial 92,457
95,509
96,531
 766,057
751,479
769,463
Industrial 34,893
32,748
33,464
 457,413
407,683
430,300
Municipal 3,248
3,571
3,707
 30,415
31,636
33,272
Subtotal Retail Revenue - Electric 203,548
207,147
206,466
 1,809,404
1,737,623
1,759,765
Contract Wholesale (a)
 19,079
33,687
30,435
 368,360
900,854
722,659
Off-system/Power Marketing Wholesale 16,475
17,692
14,271
 472,276
518,725
509,963
Other 52,117
39,554
37,261
 


Total Revenue and Energy Sold 291,219
298,080
288,433
 2,650,040
3,157,202
2,992,387
Other Uses, Losses or Generation, net (b)
 


 148,847
203,194
195,005
Total Revenue and Energy 291,219
298,080
288,433
 2,798,887
3,360,396
3,187,392
Less cost of fuel and purchased power 73,115
92,886
87,638
    
Gross Margin (non-GAAP) (c)
 $218,104
$205,194
$200,795
    
(a)2019 revenue and purchased power, as well as associated quantities, for a certain wholesale contract have been presented on a net basis, which resulted in a decrease of $12 million, or 480,400 MWh, in 2019.  Prior year amounts were presented on a gross basis and, due to their immaterial nature, were not revised.  This 2019 presentation change has no impact on Gross margin.
(b)Total MWh includes Other Uses, Losses or Generation, net, which is approximately 6%.
(c)
For further information on Gross Margin, see “Non-GAAP Financial Measure” within Management’s Discussion and Analysis of Financial Condition and Results of Operations in Item 7 of this Annual Report on Form 10-K.



In South Dakota we have an approved annual Environmental Improvement Cost Recovery Adjustment tariff which recovers costs associated with generation plant environmental improvements.

 For the year ended December 31,
Quantities Generated and Purchased (MWh)201920182017
Coal-fired1,495,309
1,598,957
1,485,254
Natural Gas and Oil273,147
135,265
96,661
Total Generated1,768,456
1,734,222
1,581,915
    
Purchased (a)
1,030,431
1,626,174
1,605,477
Total Generated and Purchased2,798,887
3,360,396
3,187,392
We have an approved FERC Transmission Tariff based on a formulaic approach that determines the revenue component of our open access transmission tariff._________________________
(a)2019 purchased power quantities for a certain wholesale contract have been presented on a net basis, which resulted in a decrease of 480,400 MWh in 2019.  Prior year amounts were presented on a gross basis and, due to their immaterial nature, were not revised.  This 2019 presentation change has no impact on Gross margin.



Rate MattersUtility Regulation Characteristics

South Dakota

On March 2, 2015, the SDPUC issued an order approving a rate stipulation and agreement authorizing an annual electric revenue increase for us of $6.9 million. The agreement was a Global Settlement and did not stipulate return on equity and capital structure. The SDPUC’s decision provides us a return on our investment in Cheyenne Prairie and associated infrastructure, and provides recovery of our share of operating expenses for this natural gas-fired facility. We implemented interim rates on October 1, 2014, coinciding with Cheyenne Prairie’s commercial operation date. Final rates were approved on April 1, 2015, effective October 1, 2014.



Transmission

On July 23, 2015, we received approval from the WPSC for a CPCN originally filed on July 22, 2014 to construct the Wyoming portion of a $54 million, 230-kV, 144 mile-long transmission line that would connect the Teckla Substation in northeast Wyoming, to the Lange Substation near Rapid City, South Dakota. We received approval on November 6, 2014 from the SDPUC for a permit to construct the South Dakota portion of this line. The first segment of this project connecting Teckla to Osage, Wyoming was energized on August 31, 2016. The second segment of the project is expected to be placed in service in the first half of 2017.


State Regulation


Certain states where we conduct electric utility operations have adopted renewable energy portfolio standards that require or encourage us to source, by a certain future date, a minimum percentage of the electricity delivered to customers from renewable energy generation facilities. At December 31, 2016,2019, we were subject to the following renewable energy portfolio standards or objectives:


Montana. In 2005, Montana established a renewable portfolio standard that requires public utilities to obtain a percentage of their retail electricity sales from eligible renewable resources. In March 2013, South Dakota Electric filed a petition with the MTPSC requesting a waiver of the renewable portfolio standards primarily due to exceeding the applicable “cost cap” included in the standards. In March 2013, the Montana Legislature adopted legislation that had the effect of excluding South Dakota Electric from all renewable portfolio standard requirements under State Senate Bill 164, primarily due to the very low number of customers South Dakota Electric has in Montana and the relatively high cost of meeting the renewable requirements.

South Dakota. South Dakota has adopted a renewable portfolio objective that encourages, but does not mandate utilities to generate, or cause to be generated, at least 10% of their retail electricity supply from renewable energy sources by 2015.
South Dakota. South Dakota has adopted a renewable portfolio objective that encourages, but does not mandate utilities to generate, or cause to be generated, at least 10% of their retail electricity supply from renewable energy sources by 2015.
Wyoming. Wyoming currently has no renewable energy portfolio standard.

Montana. In 2005, Montana established a renewable portfolio standard that requires public utilities to obtain a percentage of their retail electricity sales from eligible renewable resources. In March 2013, the Montana Legislature adopted legislation that excluded us from all renewable portfolio standard requirements under Senate Bill 164, primarily due to the very low number of customers we have in Montana and the relatively high cost of meeting the renewable requirements.

Wyoming. Wyoming currently has no renewable energy portfolio standard.


Absent a specific renewable energy mandate in South Dakota,the territories we serve, our current strategy is to prudently incorporateproactively integrate alternative and renewable energy into our resourceutility energy supply seeking to minimize associatedwhile mitigating customer rate increases for our utility customers.impacts. Mandatory portfolio standards have increased, and maywill likely continue to increase the power supply costs of our electric utility operations. Although we will seek to recover these higher costs in rates, we can provide no assurance that we will be able to secure full recovery of the costs we pay to be in compliance with standards or objectives. We cannot at this time reasonably forecast the potential costs associated with any new renewable energy standards that have been or may be proposed at the federal or state level.


Environmental RegulationsFederal Regulation

Federal Power Act. The Federal Power Act gives FERC exclusive rate-making jurisdiction over wholesale sales of electricity and the transmission of electricity in interstate commerce. Pursuant to the Federal Power Act, all public utilities subject to FERC’s jurisdiction must maintain tariffs and rate schedules on file with FERC that govern the rates, and terms and conditions for the provision of FERC-jurisdictional wholesale power and transmission services. Public utilities are also subject to accounting, record-keeping and reporting requirements administered by FERC. FERC also places certain limitations on transactions between public utilities and their affiliates. We provide FERC-jurisdictional services subject to FERC’s oversight.


We are authorized by FERC to make wholesale sales of electric capacity and energy at market-based rates under tariffs on file with FERC. As a condition of our market-based rate authority, we file Electric Quarterly Reports with FERC. We own and operate FERC-jurisdictional interstate transmission facilities and provide open access transmission service under tariffs on file with FERC. We are subject to numerous federal, stateroutine audit by FERC with respect to our compliance with FERC’s regulations.

The Federal Power Act authorizes FERC to certify and local lawsoversee a national electric reliability organization with authority to promulgate and regulations relatingenforce mandatory reliability standards applicable to the protectionall users, owners and operators of the environmentbulk-power system. FERC has certified NERC as the electric reliability organization. NERC has promulgated mandatory reliability standards and the safetyNERC, in conjunction with regional reliability organizations that operate under FERC’s and health of personnelNERC’s authority and the public. These laws and regulations affect a broad range of our utility activities, and generally regulate: (i) the protection of air and water quality; (ii) the identification, generation, storage, handling, transportation, disposal, record-keeping, labeling, reporting of, and emergency response in connection with hazardous and toxic materials and wastes, including asbestos; and (iii) the protection of plant and animal species and minimization of noise emissions. We have incurred, and expect to incur, capital, operating and maintenance costs for the operations of our plants to comply with these laws and regulations. While the requirements are evolving, it is virtually certain that environmental requirements placed on the operations will continue to be more restrictive.oversight, enforces those mandatory reliability standards.


Environmental Matters

Water Issues

Issues. Our facilities are subject to a variety of state and federal regulations governing existing and potential water/wastewater discharges and protection of surface waters from oil pollution. Generally, such regulations are promulgated under the Clean Water Act and govern overall water/wastewater discharges through NPDESEPA’s surface water discharge and storm water permits. All of our facilities that are required to have such permits have those permits in place and are in compliance with discharge limitations and plan implementation requirements. The EPA proposed effluent limitation guidelines and standards on June 7, 2013, and published the final rule on November 3, 2015. In 2017, the EPA postponed the implementation of the rule and set a timeline in 2018 to revise the rule. To date, the rule is being reviewed by the Office of Management and Budget. This rule will have an impact on the Wyodak Plant, requiring conversion to a dry method of handling coal ash and further restrictions of constituent concentrations in any off-site discharges. Our share of those costs is estimated at $1.8 million.Plant. Until the EPA issues the rule for publication, we cannot quantify what the potential impact may be on the Wyodak Plant. The terms of this new regulation become effective atmay impact the next permit renewal which will be in 2020.



Short-term Emission Limits. The EPA and State Air Quality Programs implemented short-term emission limits for coal and natural gas-fired generating units during normal and start-up operating scenarios for Sulfur Dioxide (SO2), Nitrogen Oxide (NOx) and opacity. The limits pertain to emissions during start-up periods and upset conditions such as mechanical malfunctions. State and federal regulatory agencies typically excuse short-term emissions exceedances if they are reported and corrected immediately or if it occurs during start-up.
Additionally, the EPA regulates surface water oil
We proactively manage this requirement through maintenance efforts and installing additional pollution through its oil pollution prevention regulations. Allcontrol systems to control SO2 emission short-term excursions during start-up. These actions have nearly eliminated our short-term emission limit compliance risk while plant availability remained above 90% for all four of our facilities subjectcoal-fired plants. To eliminate the remaining potential for exceedances, an innovative trip logic mechanism was implemented to these regulationsshut the power plant down if a predicted emission limit is to be exceeded. Similar efforts have compliant prevention plans in place.been taken and similar results achieved with our natural gas fired combustion turbine sites as well.


Clean Air Act

Title IV of the Clean Air Act created an SO2 allowance trading regime as part of the federal acid rain program. Each allowance gives the owner the right to emit one ton of SO2.Certain facilities are allocated allowances based on their historical operating data. At the end of each year, each emitting unit must possess allowances sufficient to cover its emissions for the preceding year. Allowances may be traded, so affected units that expect to emit more SO2 than their allocated allowances may purchase allowances on the open market.

Title IV applies to several of our generation facilities, including the Neil Simpson II, Neil Simpson CT, Lange CT, Wygen III, Cheyenne Prairie and Wyodak plants. Without purchasing additional allowances, we currently hold sufficient allowances to satisfy Title IV at all such plants through 2046. We expect to integrate the cost of obtaining the required number of allowances needed for future projects into our overall financial analysis of such new projects.

Title V of the Clean Air Act requires that all of our generating facilities obtain operating permits. All of our existing facilities have received Title V permits, with the exception of Wygen III and Cheyenne Prairie Generating Station. Wygen III and Cheyenne Prairie Generating Station are allowed to operate under their construction permit until the Title V permit is issued by the state. The Title V application for Wygen III was submitted in January 2011, with the permit expected in 2017. The Cheyenne Prairie Generating Station Title V application was submitted in 2015, with the permit expected in 2017. All applications were filed in accordance with regulatory requirements.

On February 16, 2012, the EPA published in the Federal Register the National Emission Standards for Hazardous Air Pollutants from Coal and Oil Fired Electric Utility Steam Generating Units (MATS), with an effective date of April 16, 2012. This rule imposes requirements for mercury, acid gases, metals and other pollutants. As of April 16, 2016, all plants are in compliance.

In August 2012, the EPA proposed revisionsRegional Haze (Impacts to the Electric Utility New Source Performance Standards for stationary combustion turbines. This rule is expected to be finalized in 2017 and, as proposed, will be applicable to Cheyenne Prairie and eventually all the combustion turbines in our fleet. Among other things, the rule seeks to eliminate startup exemptions and clearly define overhauls for impact on the EPA’s New Source Review regulations, with the intention of eventually bringing all units under the applicability of this rule. Wyodak Power Plant). The primary impact is expected to be on our older existing units, which will eventually be required to meet tighter NOx emission limitations.

Regional Haze

TheEPA Regional Haze Program is an EPA rule was promulgated to improve visibility in our National Parks and Wilderness Areas.The stateState of Wyoming is currently developingproposed controls in its 2017 initial progress report under the EPA’s Regional Haze Program. Neil Simpson II is not currently a discussion item in that draft report, but could beState Implementation Plan (SIP) which allowed PacifiCorp to install low-NOx burners in the future.

Wyodak Plant, of which we own 20%. The Wyodak Power Plant is includedEPA did not agree with the State of Wyoming’s determination and overruled it in EPA’s January 30, 2014 Regional Hazea Federal Implementation Plan which includes significant additional NOx controls by March 1, 2019. Our share of those costs is estimated at $20 million.(FIP). The State of Wyoming and PacifiCorp filed requests for reconsideration and Administrative Stay with EPA andother interested parties are challenging the United States CourtEPA’s determination. If the challenge is unsuccessful, additional capital investment would be necessary to bring the Wyodak Plant into compliance. Our 20% share of Appealsthis capital investment for the 10th Circuit. On September 9, 2014,facility would be approximately $27 million if PacifiCorp is required to install a Selective Catalytic Reactor for NOx control. The case is currently held in abeyance in the 10th Circuit stayed EPA’s NOx requirement for Wyodak pending outcomeCourt as the parties work on a settlement. Basin Electric, who is part of the appeal, whichlegal action, settled with the EPA. In lieu of going to court, PacifiCorp entered into mediation with the EPA and conservation groups. PacifiCorp submitted a “Request for Reconsideration” on October 24, 2019 to the EPA and provided a copy to the court. The purpose of the submittal is anticipated to be settled byrevisit the summeremission impacts and cost of 2017.additional investment.


Greenhouse Gas Regulations

Affordable Clean Energy Rule. The GHG Tailoring Rule, effective June 2010, will impact us in the event of a major modification at an existing facility or in the event of a new major source as defined by EPA regulations. Upon renewal of operating permits for existing facilities, monitoringwas directed to repeal, revise, and reporting requirements will be implemented. New projects or major modifications to existing projects will result in a Best Available Control Technology review that could impose more stringent emissions control practices and technologies. The EPA’s GHG New Source Performance Standard for new steam electric generating units, published October 2015, effectively prohibits new coal-fired units until carbon capture and sequestration becomes technically and economically feasible.



The portion of this rule-making that applies to existing power generation sources is known asreplace the Clean Power Plan (CPP).rule. On August 31, 2018, the EPA published the proposed Affordable Clean Energy rule. The portion of this rule-making thatrule focuses on heat rate improvements on coal-fired boiler units. In July 2019, the rule was finalized and applies only to new generating units effectively prohibits newour coal-fired powerplants. These plants from being constructed until carbon capture and sequestration becomes technically and economically feasible. The objectivehave implemented, or plan to implement, a majority of the CPP regulation isefficiency requirements listed in the rule.

Environmental risk changes constantly with the implementation of new or modified regulations, changing stakeholder interests and needs, and through the introduction of innovative work practices and technologies. We assess risk annually and develop mitigation strategies to decrease existing coal-fired generation, increasesuccessfully and responsibly manage and ensure compliance across the utilization of existing gas-fired combined cycle generation, increase renewable energyenterprise. For additional information on environmental matters, see Item 1A and increase use of demand side management. The U.S. Supreme Court entered an order staying the CPP in February 2016, pending appeal. The effectNote 13 of the order isNotes to delay the CPP’s compliance deadlines until challenges to the CPP have been fully litigated and the U.S. Supreme Court has ruled. If the CPP is implemented in its current form, we cannot predict the terms of state plans and any limits on CO2 emissions at our existing plants could have a material impact on our customer rates, financial position, results of operations and/or cash flows. In 2015 and again in 2016, we met with staff of state air programs and public utility commissions on several occasions. We will continue to work closely with state regulatory staff as these plans develop.

Wyoming passed GHG legislation in 2012 and 2013, enabling the state to implement the EPA’s GHG program. Wyoming adopted and submitted a GHG regulatory program to the EPA, which the EPA approved and published in 2013. Wyoming has full jurisdiction over the GHG permitting program which includes the transfer of the Cheyenne Prairie EPA GHG air permit, to the state of Wyoming. This eliminates the increased time, expense and considerable risk of obtaining a permit from the EPA.

In 2016, we reported 2015 GHG emissions from our generation facilities in order to comply with the EPA’s GHG Annual Inventory regulation, issued in 2009. We continue to report annual GHG emissions as required by the EPA. Climate change issues are the subject of a number of lawsuits, the outcome of which could impact the utility industry. We will continue to review GHG impacts as legislation or regulation develops and litigation is resolved.

New or more stringent regulations or other energy efficiency requirements could require us to incur significant additional costs relating to, among other things, the installation of additional emission control equipment, the acceleration of capital expenditures, the purchase of additional emissions allowances or offsets, the acquisition or development of additional energy supply from renewable resources and the closure of certain generating facilities. To the extent our regulated fossil-fuel generating plants are included in rate base, we will attempt to recover costs associated with complying with emission standards or other requirements. We will also attempt to recover the emission compliance costs of our non-regulated fossil-fuel generating plants from utility customers and other purchasers of the power generated by our non-regulated power plants, including utility affiliates. Any unrecovered costs could have a material impact on our results of operations, financial position and/or cash flows. In addition, future changes in environmental regulations governing air emissions could render some of our power generating units more expensive or uneconomical to operate and maintain. The results of the 2016 U.S. elections add uncertainty as to the final disposition of recently enacted and proposed EPA regulations, including the Clean Power Plan. We will continue to monitor new developments for potential impacts to our operations.

Regulatory Accounting

We follow accounting for regulated utility operations and our financial statements reflect the effects of the different rate making principles followed by the various jurisdictions in which we operate. If rate recovery becomes unlikely or uncertain, due to competition or regulatory action, these accounting standards may no longer apply to our regulated operations. In the event we determine that we no longer meet the accounting criteria for regulated operations, the accounting impact to us could be an extraordinary non-cash charge to operations of an amount that could be material.

New Accounting Pronouncements

See Note 1 of our Notes to Financial Statements in this Annual Report on Form 10-K10-K.

Other Properties

In addition to the facilities previously disclosed in Items 1 and 2, we own several facilities throughout our service territories. Our owned facilities are as follows:

In Rapid City, South Dakota, we have a 220,000 square foot corporate headquarters building, Horizon Point, which was completed in 2017.

In South Dakota and Wyoming, we own various office, service center, storage, shop and warehouse space totaling approximately 103,000 square feet.

Substantially all of our tangible utility properties are subject to liens securing first mortgage bonds.

Employees

At December 31, 2019, we had 217 employees. Approximately 62% of our employees are represented by a union. We have not experienced any labor stoppages in recent years. At December 31, 2019, approximately 30% of our employees were eligible for information on new accounting standards adopted in 2016regular (age 65 with at least 5 years of service) or pending adoption.early (ages 55 to 64 with at least 5 years of service) retirement.

At December 31, 2019, certain employees were covered by the following collective bargaining agreement:
UtilityNumber of EmployeesUnion AffiliationExpiration Date of Collective Bargaining Agreement
South Dakota Electric135
IBEW Local 1250March 31, 2024





ITEM 1A.    RISK FACTORS


OPERATING RISKS

The nature of our business subjects us to a number of uncertainties and risks. The followingRisks that may adversely affect the business, financial condition, results of operations or cash flows are described below. These risk factors and other risk factors that we discuss in our periodic reports filed with the SEC should be considered for a better understanding of our Company. These important factors

Our continued success is dependent on execution of our strategic business plans and other matters discussed herein could causegrowth strategy.

Our results of operations depend, in significant part, on our actual results or outcomesability to differ materially.

Regulatory commissions may refuse to approve some or all of the utility rate increases we have requested or may requestexecute our strategic business plans and growth strategy. Technology advancements, disruptive forces and innovations in the future,marketplace and changing business or regulatory conditions may determine that amounts passed throughnegatively impact our current plans and strategies. An inability to customers were not prudently incurredsuccessfully and therefore are not recoverable.timely adapt to changing conditions could materially affect our financial operating results including earnings, cash flow and liquidity.


We may be subject to unfavorable federal and state regulatory outcomes.

Our electricity operations areregulated Electric Utility is subject to cost-of-service regulation and earnings oversight from federal and three state utility commissions. This regulatory treatment does not provide any assurance as to achievement of desired earnings levels. Our retail electric utility rates are regulated on a state-by-state basis by the relevant state regulatory authorities based on an analysis of our costs, as reviewed and approved in a regulatory proceeding. The rates that we are allowed to charge may or may not match our related costs and allowed return on invested capital at any given time. While rate regulation is premised on the full recovery of prudently incurred costs and a reasonable rate of return on invested capital, there can be no assurance that theeach state public utility commissionscommission will judge all of our costs, including our direct and allocated borrowing and debt service costs to have been prudently incurred or that the regulatory process in which rates are determined will always result in rates that produce a full recovery of our costs and the allowed return on invested capital allowedcapital. In addition, rate decisions could be influenced by many factors, including general economic conditions and the applicable state public utility commission.political environment.


To some degree, we areOur Electric Utility is permitted to recover certain costs (such as increased fuel and purchased power and transmission costs, as applicable) without having to filecosts) outside of a base rate case.review. To the extent we are able to pass through such costs to our customers, and athe state public utility commission subsequently determines that such costs should not have been paid by customers;the customers, we may be required to refund such costs to customers.costs. Any such costs not recovered through rates, or any such refund, could adversely affect financial operating results including earnings, cash flow and liquidity.

We may be subject to future laws, regulations, or actions associated with fossil-fuel generation and GHG emissions.

We own and operate regulated electric power plants that burn fossil fuels (natural gas and coal). This business activity is subject to evolving public concern regarding fossil fuels, GHG emissions (such as carbon dioxide and methane) and their impact on the climate.

Increased rules and regulations associated with fossil fuels and GHG emissions could result in the impairment or retirement of some of our existing or future transmission, distribution and generation facilities. Further, these rules could create the need to purchase or build clean-energy fuel sources to fulfill obligations to our customers. These actions could also result in increased operating costs which could adversely impact customers and our financial operating results of operations, financial position orincluding earnings, cash flows.flow and liquidity.

Our financial performance depends on the successful operationmanagement of our facilities. Iffacilities operations, including ongoing operation, construction, expansion, and refurbishment.

Operation, construction, expansion and refurbishment of electric generating facilities and electric transmission and distribution systems involve risks that could result in fires, explosions, property damage and personal injury, including death. These risks include:

Inherent dangers. Electricity is dangerous for employees and the risks involvedgeneral public; contact with power lines and electrical facilities and equipment can result in fires and explosions, causing significant property damage and personal injuries, including death;


Weather, natural conditions and disasters. Severe weather events could negatively impact operations, including our operationsability to provide energy safely and reliably and our ability to complete construction, expansion or refurbishment of facilities as planned. Extreme natural conditions and other disasters such as wind, lightning, flooding and winter storms, can cause wildfires, electric transmission or distribution pole failures, outages, property damage and personal injury;

Operating hazards. Operating hazards such as leaks, mechanical problems and accidents, including fires or explosions could impact employee and public safety, reliability and customer confidence;

Labor and labor relations. The cost of recruiting and retaining skilled technical labor or the unavailability of such resources could have a negative impact on our operations. Our ability to transition and replace our retirement-eligible utility employees is a risk; at December 31, 2019, approximately 30% of our employees were eligible for regular or early retirement. Our ability to avoid or minimize supply interruptions, work stoppages and labor disputes is also a risk; approximately 62% of our employees are not appropriately managedrepresented by a collective bargaining agreement;

Equipment and processes. Breakdown or mitigated, our operations may not be successfulfailure of equipment or processes, the unavailability or increased cost of equipment, and thisperformance below expected levels of output or efficiency could adversely affectnegatively impact our results of operations. New plants may employ recently developed and technologically complex equipment, including newer environmental emission control technology;


Operating electric generatingDisrupted transmission and distribution. We depend on transmission and distribution facilities, involves risks, including:including those operated by unaffiliated parties, to deliver the electricity that we sell to our retail and wholesale customers. If transmission is interrupted physically, mechanically, or with cyber means, our ability to sell or deliver product and satisfy our contractual obligations may be hindered;

Operational limitations imposed by environmental and other regulatory requirements;


Interruptions to supply of fuel and other commodities used in generation and distribution. We purchase fuel from a number of suppliers. Our results of operations could be negatively impacted by disruptions in the delivery of fuel due to various factors, including but not limited to, transportation delays, labor relations, weather and environmental regulations, which could limit our utility’s ability to operate facilities;

Replacement power. The cost of supplying or securing replacement power during scheduled and unscheduled outages of generation facilities could negatively impact our results of operations;

Governmental permits. The inability to obtain required governmental permits and approvals along with the cost of complying with or satisfying conditions imposed upon such approvals could negatively impact our ability to operate and our results of operations;

Operational limitations. Operational limitations imposed by environmental and other regulatory requirements and contractual agreements, including those that restrict the timing of generation plant scheduled outages, could negatively impact our results of operations;

Increased costs. Increased capital and operating costs to comply with increasingly stringent environmental laws and regulations; unexpected engineering, environmental and geological problems; and unanticipated cost overruns could negatively impact our results of operations;

Public opposition. Opposition by members of public or special-interest groups could negatively impact our ability to operate our facilities;businesses; and

Breakdown or failure of equipment or processes, including those operated by PacifiCorp at the Wyodak plant;

Our ability to transition and replace our retirement-eligible employees;

Inability to recruit and retain skilled technical labor;

Disrupted transmission and distribution. We depend on transmission and distribution facilities, including those operated by unaffiliated parties, to deliver the electricity that we sell to our retail and wholesale customers. If transmission is interrupted, our ability to sell or deliver product and satisfy our contractual obligations may be hindered;

Electricity is dangerous for employees and the general public should they come in contact with power lines or electrical service facilities and equipment. Natural conditions and other disasters such as wind, lightning and winter storms can cause wildfires, pole failures and associated property damage and outages;


Disruption in the functioning of our information technology and network infrastructure which areis vulnerable to disability, failures and unauthorized access. If our information technology systems were to fail and we were unable to recover in a timely manner, we would be unable to fulfill critical business functions; andfunctions.

Labor relations.



Construction, expansion, refurbishment and operation of power generating and transmission facilities involve significant risks which could reduce profitability.

The construction, expansion, refurbishment and operation of power generating and transmission facilities involve many risks, including:

The inability to obtain required governmental permits and approvals along with the cost of complying with or satisfying conditions imposed upon such approvals;

Contractual restrictions upon the timing of scheduled outages;

The cost of supplying or securing replacement power during scheduled and unscheduled outages;

The unavailability or increased cost of equipment;

The cost of recruiting and retaining or the unavailability of skilled labor;

Supply interruptions, work stoppages and labor disputes;

Increased capital and operating costs to comply with increasingly stringent environmental laws and regulations;

Opposition by members of the public or special-interest groups;

Weather interferences;

Availability and cost of fuel supplies;

Unexpected engineering, environmental or geological problems; and

Unanticipated cost overruns.

The ongoing operation of our facilitiesbusiness involves many of the risks described above, in addition to risks relating to the breakdown or failure of equipment or processes and performance below expected levels of output or efficiency. New plants may employ recently developed and technologically complex equipment, including newer environmental emission control technology.above. Any of these risks could cause us to experience negative financial results and damage to our reputation and public confidence. These risks could cause us to incur significant costs, be unable to deliver energy and/or operate below expected capacity levels, which in turn could reduce revenues increase expenses or cause us to incur higher operating and maintenance costs and penalties. While we maintain insurance and we obtain warranties from vendors and obligate contractors to meet certain performance levels, the proceeds of such insurance and our rights under contracts, warranties or performance guarantees may not be timely or adequate to cover lost revenues, increased expenses, liability or liquidated damage payments.

Our revenues,energy production, transmission and distribution activities involve numerous risks that may result in accidents and other catastrophic events.

Inherent in our business is a variety of hazards and operating risks, such as leaks, blowouts, fires, releases of hazardous materials, explosions and operational problems. Many of our transmission and distribution assets are located near populated residential areas, commercial business centers and industrial sites.

These hazards could result in injury or loss of human life, cause environmental pollution, significantly damage property or natural resources and impair our ability to operate our facilities. While we maintain liability and property insurance coverage, such policies are subject to certain limits and deductibles. The occurrence of any of these events may not be fully covered by our insurance and could have a material adverse effect on our financial operating results of operationsincluding earnings, cash flow and financial condition are impacted by customerliquidity.

Customer growth and usage in our service territories and may fluctuate with current economic conditions, emerging technologies or responses to price increases.


Our revenues,financial operating results of operations and financial condition are impacted by demand in our service territories. Customer growth and usage may be impacted by a number of factors, including:including the voluntary reduction of consumption of electricity and natural gas by our customers in response to increases in prices and demand-side managementenergy efficiency programs, economic conditions impacting decreases in customers’ disposable income and the use of distributed generation resources or other emerging technologies. Continued technological improvements may make customer and third-party distributed generation and energy storage systems, including fuel cells, micro-turbines, wind turbines, solar cells and batteries, more cost effective and feasible for our customers. If more customers utilize their own generation, demand for energy from us would decline. Such developments could affect the price of energy and delivery of energy, require further improvements to our distribution systems to address changing load demands and could make portions of our electric system power supply and transmission and/or distribution facilities obsolete prior to the end of their useful lives.  Each of these factors could materially affect our financial operating results including earnings, cash flow and liquidity.

Cyberattacks, terrorism, or other malicious acts could disrupt our operations, or lead to a loss or misuse of confidential and proprietary information.

To effectively operate our business, we rely upon a sophisticated electronic control system, SCADA, information technology systems and network infrastructure to collect and retain sensitive information including personal information about our customers and employees. Cyberattacks, terrorism or other malicious acts targeting electronic control systems could result in a full or partial disruption of our operations. Attacks targeting other key information technology systems, including our third-party vendors’ information systems, could further add to a full or partial disruption of our operations. Any disruption of these operations financial positioncould result in a loss of service to customers and cash flows.a significant decrease in revenues, as well as significant expense to repair system damage and remedy security breaches. Any theft, loss and/or fraudulent use of customer, shareowner, employee or proprietary data could subject us to significant litigation, liability and costs, as well as adversely impact our reputation with customers and regulators, among others.



Our operations rely on storage and transportation assets owned by third parties to satisfy our obligations.


We rely on pipeline companieshave instituted security measures and other ownerssafeguards to protect our operational systems and information technology assets, including certain safeguards required by FERC. The security measures and safeguards we have implemented may not always be effective. Despite our implementation of gas storage facilitiessecurity measures and safeguards, all of our information technology systems may be vulnerable to deliver natural gas to our natural gas-fired power plants. If storage capacity is inadequatedisability, failures or transportation is disrupted,unauthorized access.

Risks associated with deployment of capital may impact our ability to satisfyexecute our obligations maybusiness plans and growth strategy.

We have significant capital investment programs planned for the next five years. The successful execution of our capital investment strategy depends on, or could be hindered. Asaffected by, a result, we may be responsible for damages incurred by our counterparties, such as the additionalvariety of factors that include, but are not limited to: extreme weather conditions, effective management of projects, availability of qualified construction personnel, including contractors, changes in commodity and other prices, governmental approvals and permitting and regulatory cost of acquiring alternative supply at then-current market rates, or for penalties imposed by state regulatory authorities.recovery.


National and regional economicWeather conditions may cause increased counterparty risk, late payments and uncollectible accounts, which could adversely affect our results of operations, financial position and liquidity.

A future recession may lead to an increasefluctuation in late payments from retail, commercial and industrial utility customers,customer usage as well as from our non-regulated customers. If late payments and uncollectible accounts increase, earnings and cash flows from our continuing operations may be reduced.service disruptions.

Our credit ratings could be lowered below investment grade in the future. If this were to occur, it could impact our access to capital, our cost of capital and our other operating costs.

Our credit rating on our First Mortgage Bonds is A1 by Moody’s, A- by S&P and A by Fitch. Reduction of our credit ratings could impair our ability to refinance or repay our existing debt and to complete new financings on reasonable terms, or at all. A credit rating downgrade could also result in counterparties requiring us to post additional collateral under existing or new contracts or trades.

Prices for some of our products and services as well as a portion of our operating costs are volatile and may cause our revenues and expenses to fluctuate significantly.

A portion of our net income is attributable to sales of contract and off-system wholesale electricity. The related power prices are influenced by many factors outside our control, including, among other things, fuel prices, transmission constraints, supply and demand, weather, general economic conditions, and the rules, regulations and actions of the system operators in those markets. Moreover, unlike most other commodities, electricity cannot be stored and therefore must be produced concurrently with its use. As a result, wholesale power markets may be subject to significant, unpredictable price fluctuations over relatively short periods of time.

Our energy production, transmission and distribution activities involve numerous risks that may result in accidents and other catastrophic events that could give rise to additional costs and cause a substantial loss to us.

Inherent in our electricity transmission and distribution activities are a variety of hazards and operating risks, such as fires, releases of hazardous materials, explosions and operational problems. These events could impact the safety of employees or others and result in injury or loss of human life, and cause significant damage to property or natural resources (including public lands), environmental pollution, impairment of our operations, and substantial financial losses to us. Particularly for our transmission and distribution lines located near populated areas, including residential areas, commercial business centers, industrial sites and other public gathering areas, the damages resulting from any such events could be substantial. While we maintain liability and property insurance coverage, such policies are subject to certain limits and deductibles. The occurrence of any of these events not fully covered by our insurance could have a material adverse effect on our financial position, results of operations or cash flows.

Operating results can be adversely affected by variations from normal weather conditions.


Our utility business is a seasonal business and weather conditions and patterns can have a material impact on our operating performance. Demand for electricity is typically greater in the summer and winter months associated with cooling and heating.heating, respectively. Accordingly, our utility operations have historically generated lower revenues and income when weather conditions are cooler than normal in the summer and warmer than normal in the winter. Unusually mild summers and winters, therefore, could have an adverse effect on our results of operations, financial condition andposition or cash flows.


Our business is located in areas that could be subject to seasonal natural disasterssevere weather events such as severe snow and ice storms, tornadoes, strong winds, significant thunderstorms, flooding and wildfires.drought. These factorsevents could result in interruption of our business,lost operating revenues due to outages, property damage, to our property such as powerincluding inoperable generation facilities and downed transmission and distribution lines, and substations, and repair and clean-up costs associated with these storms.storm restoration activities. We may not be able to recover the costs incurred in restoring transmission and distribution property following these natural disasters through a change in our regulated rates therebyweather events resulting in a negative impact on our financial operating results including earnings, cash flow and liquidity.

We may be subject to increased risks of operations,regulatory penalties.

Business activities in the energy sector are heavily regulated, primarily by agencies of the federal government. Many agencies employ mandatory civil penalty structures for regulatory violations. The FERC, NERC, CFTC, EPA, OSHA and SEC may impose significant civil and criminal penalties to enforce compliance requirements relative to our business, which could have a material adverse effect on our financial conditionoperating results including earnings, cash flow and cash flows.liquidity.




The costsCertain Federal laws provide special protection to achieve or maintain compliance with existing or future governmentalcertain designated animal species. These laws regulations or requirements, and any failurestate equivalents provide for significant civil and criminal penalties for non-permitted activities that result in harm to do so, could adversely affect our resultsor harassment of certain protected animals, including damage to their habitats. If such species are located in an area in which we conduct operations, financial position or liquidity.

Our business isif additional species in those areas become subject to extensive energy, environmentalprotection, our operations and other lawsdevelopment projects, particularly transmission, generation and regulations of federal, state and local authorities. We generally must obtain and comply with a variety of regulations, licenses, permits and other approvals in order to operate, whichwind projects, could require significant capital expenditures and operating costs. If we fail to comply with these requirements,be restricted or delayed, or we could be subjectrequired to civil or criminal liability and the imposition of penalties, liens or fines, claims for property damage or personal injury, and/or environmental clean-up costs. In addition, existing regulations may be revised or reinterpreted and new laws and regulations may be adopted or become applicable to us or our facilities, which could require additional unexpected expenditures or cause us to reevaluate the feasibility of continued operations at certain sites and have a detrimental effect on our business.implement expensive mitigation measures.

Future steps to bring our facilities into compliance, if necessary, could be expensive and could adversely affect our results of operations and financial condition. Environmental compliance expenditures could be substantial in the future if the trend towards stricter standards, greater regulation, more extensive permitting requirements and an increase in the number of assets we operate continues.

Our ability to obtain insurance and the terms of any available insurance coverage could be adversely affected by international, national, state or local events and company-specific events, as well as the financial condition of insurers. Our insurance coverage may not provide protection against all significant losses.

Our ability to obtain insurance, as well as the cost of such insurance, could be affected by developments affecting insurance businesses, international, national, state or local events and company-specific events, as well as the financial condition of insurers. Insurance coverage may not continue to be available at all, or at rates or on terms similar to those presently available to us. A loss for which we are not fully insured could materially and adversely affect our financial results. Our insurance may not be sufficient or effective under all circumstances and against all hazards or liabilities to which we may be subject, including but not limited to environmental hazards, fire-related liability from natural events or inadequate facility maintenance, distribution property losses and cyber-security risks.


Municipal governments may seek to limit or deny our franchise privileges which could inhibit our ability to secure adequate recovery of our investment in assets subject to condemnation.privileges.


Municipal governments within our utility service territories possess the power of condemnation and could establish a municipal utility within a portion of our current service territories by limiting or denying franchise privileges for our operations and exercising powers of condemnation over all or part of our utility assets within municipal boundaries. Although condemnation is a process that is subject to constitutional protections requiring just and fair compensation, as with any judicial procedure, the outcome is uncertain. If a municipality sought to pursue this course of action, we cannot assure that we would secure adequate recovery of our investment in assets subject to condemnation.

FINANCING RISKS

A sub-investment grade credit rating could impact our ability to access capital markets.

Our issuer credit rating is A1 by Moody’s, A by S&P and A by Fitch. Reduction of our credit ratings could impair our ability to refinance or repay our existing debt and complete new financings on reasonable terms, if at all. A credit rating downgrade, particularly to sub-investment grade, could also result in counterparties requiring us to post additional collateral under existing or new contracts. In addition, a ratings downgrade would increase our interest expense under some of our existing debt obligations.

Market performance or changes in key valuation assumptions could require us to make significant unplanned contributions to our pension plans and other postretirement benefit plans.

Assumptions related to interest rates, expected return on investments, mortality and other key actuarial assumptions have a significant impact on our funding requirements and the expense recognized related to these plans. An adverse change to key assumptions associated with our defined benefit retirement plans may require significant unplanned contributions to the plans which could adversely affect our financial operating results including earnings, cash flow and liquidity.


FederalWe may be unable to obtain financing on reasonable terms needed to refinance debt, fund planned capital expenditures or otherwise execute our operating strategy.

Our ability to execute our operating strategy is highly dependent upon our access to capital. Historically, we have addressed our liquidity needs (including funds required to make scheduled principal and interest payments, refinance debt and fund working capital and planned capital expenditures) with operating cash flow, borrowings under credit facilities, proceeds of debt and equity offerings and proceeds from asset sales. Our ability to access the capital markets and the costs and terms of available financing depend on many factors, including changes in our credit ratings, changes in the federal or state regulatory environment affecting energy companies, volatility in electricity prices and general economic and market conditions.

National and regional economic conditions may cause increased counterparty credit risk, late payments and uncollectible accounts.

A future recession, if one occurs, may lead to an increase in late payments from retail, commercial and industrial utility customers. If late payments and uncollectible accounts increase, earnings and cash flows from our continuing operations may be reduced.

Our ability to obtain insurance and the terms of any available insurance coverage could be adversely affected by international, national, state or local events and company-specific events, as well as the financial condition of insurers. Our insurance coverage may not provide protection against all significant losses.

Our ability to obtain insurance, as well as the cost of such insurance, could be impacted by developments affecting insurance businesses, international, national, state or local events, as well as the financial condition of insurers. Insurance coverage may not continue to be available at all, or at rates or on terms similar to those presently available to us. A loss for which we are not fully insured could materially and adversely affect our financial results. Our insurance may not be sufficient or effective under all circumstances and against all hazards or liabilities to which the Company may be subject, including but not limited to environmental hazards, fire-related liability from natural events or inadequate facility maintenance, distribution property losses and cyber-security risks.

Costs associated with our healthcare plans and other benefits could increase significantly.

The costs of providing healthcare benefits to our employees and retirees have increased substantially in recent years. We believe that our employee benefit costs, including costs related to healthcare plans for our employees and former employees, will continue to rise. Significant regulatory developments have, and likely will continue to, require changes to our current employee benefit plans and in our administrative and accounting processes. Our electric utility rates are regulated on a state-by-state basis by the relevant state regulatory authorities based on an analysis of our costs, as reviewed and approved in a regulatory proceeding. Within our utility rates we have generally recovered the cost of providing employee benefits. As benefit costs continue to rise, there can be no assurance that the state public utility commissions will allow recovery. The increasing cost, or inadequate recovery of, rising employee benefit costs may adversely affect our financial operating results including earnings, cash flow or liquidity.

An effective system of internal control may not be maintained, leading to material weaknesses in internal control over financial reporting.

Section 404 of the Sarbanes-Oxley Act of 2002 requires management to make an assessment of the design and effectiveness of internal controls. Our independent registered public accounting firm is required to attest to the effectiveness of these controls. During their assessment of these controls, management or our independent registered public accounting firm may identify areas of weakness in control design or effectiveness, which may lead to the conclusion that a material weakness in internal control exists. Any control deficiencies we identify in the future could adversely affect our ability to report our financial results on a timely and accurate basis, which could result in a loss of investor confidence in our financial reports or have a material adverse effect on our ability to operate our business or access sources of liquidity.

A control system, no matter how well designed and operated, can provide only reasonable, not absolute, assurance that the control system’s objectives will be met. If we are unable to assert that our internal controls over financial reporting are effective, market perception of our business, operating results and stock price could be adversely affected.


ENVIRONMENTAL RISKS

Developments in federal and state laws concerning greenhouse gasGHG regulations and air emissions mayrelating to climate could materially increase our generation and production costs and could render some of our generating units uneconomical to operate and maintain.

To the extent climate change occurs, our businesses could be adversely impacted. Warmer temperatures during the heating season or cooler temperatures during the cooling season in our service territories could adversely affect financial results through lower MWh sold and associated lower revenues.

We own and operate regulated fossil-fuel generating plants in South Dakota and Wyoming. Recent developmentsDevelopments under federal and state laws and regulations governing air emissions from fossil-fuel generating plants may result in more stringent emission limitations, which could have a material impact on our costs of operations. Various pending or final state and EPA regulations that will impact our facilities are also discussed in Item 1 of this Annual Report on Form 10-K under the captionsection “Environmental Regulations.”Matters”.
The GHG Tailoring Rule, effective June 2010 will impact us
There is uncertainty surrounding current climate regulation due to legal challenges, new federal climate legislation anticipated in the event of a major modification at an existing facilityfuture, or in the event of a new major source as defined by EPA regulations. Upon renewal of operating permits for existing facilities, monitoringstate climate legislation and reporting requirements will be implemented. New projects or major modifications to existing projects will result in a Best Available Control Technology review that could impose more stringent emissions control practices and technologies. The EPA’s GHG New Source Performance Standard for new steam electric generating units, published October 2015, effectively prohibits new coal-fired units until carbon capture and sequestration becomes technically and economically feasible.


On October 23, 2015, the EPA finalized the CPP to cut carbon emissions from existing electric generating units. The design of the CPP is to decrease existing coal-fired generation, increase the utilization of existing gas generation, increase renewable energy and demand side management. The rule, which does not propose to regulate individual emission sources, calls for each state to develop plans to meet the EPA-assigned statewide average emission rate target for that state by 2030. The rule also allows states to formulate a regional approach whereby they would join with other states and be assigned a new single target for the group. The U.S. Supreme Court entered an order staying the CPP in February 2016, pending appeal. The effect of the order is to delay the CPP’s compliance deadlines until challenges to the CPP have been fully litigated and the U.S. Supreme Court has ruled. In 2015 and again in 2016, we met with the staff of state air programs and public utility commissions on several occasions.regulation. We will continue to work closely with state regulatory staff as these plans develop.

Due to uncertainty as to the final outcome of federal climate change legislation, legal challenges, state clean power plan developments or regulatory changes under the Clean Air Act, we cannot definitively estimate the effect of GHG legislation or regulation on our results of operations, financial position or cash flows or financial position.flows.


New or more stringent regulations or other energy efficiency requirements could require us to incur significant additional costs relating to, among other things, the installation of additional emission control equipment, the acceleration of capital expenditures, the purchase of additional emissions allowances or offsets, the acquisition or development of additional energy supply from renewable resources, the closure or reduction of load of coal generatingcoal-fired power generation facilities and potential increased load of our combined cycle natural gas firedgas-fired generation units. To the extent our regulated fossil-fuel generating plants are included in rate base we will attempt to recover costs associated with complying with emission standards or other requirements. Any unrecovered costs could have a material impact on our results of operations and financial condition. In addition, future changes in environmental regulations governing air emissions could render some of our power generating units more expensive or uneconomical to operate and maintain.
Increased risks of regulatory penaltiesmaintain; this could negativelycause those generating units to be de-commissioned, potentially resulting in impairment costs. We will attempt to recover any remaining asset value; however, any unrecovered costs could have a material impact on our results of operations and financial positioncondition.

The costs to achieve or liquidity.maintain compliance with existing or future governmental laws, regulations or requirements, or failure to comply, could increase significantly.


Business activitiesWe are subject to numerous environmental laws and regulations affecting many aspects of present and future operations, including air emissions, water quality, wastewater discharges, solid waste and hazardous waste. These laws and regulations may result in increased capital, operating and other costs. These laws and regulations generally require us to obtain and comply with a wide variety of environmental licenses, permits, inspections and other approvals. Compliance with environmental laws and regulations may require significant expenditures, including expenditures for cleanup costs and damages arising from contaminated properties. Failure to comply with environmental regulations may result in the energy sector are heavily regulated, primarily by agenciesimposition of fines, penalties and injunctive measures affecting operating assets.

We may not be successful in recovering capital and operating costs incurred to comply with new environmental regulations through existing regulatory rate structures and contracts with customers. More stringent environmental laws or regulations could result in additional costs of operation for existing facilities or impede the federal government. Agenciesdevelopment of new facilities. Although it is not expected that historically sought voluntary compliance, or issued non-monetary sanctions, now employ mandatory civil penalty structures for regulatory violations. The FERC, NERC, CFTC, EPA, OSHA and SEC may impose significant civil and criminal penaltiesthe costs to enforce compliance requirements relative to our business, which couldcomply with current environmental regulations will have a material adverse effect on our operations and/or our financial results.

Certain Federal laws, including the Migratory Bird Act and the Endangered Species Act, provide special protection to certain designated species. These laws and any state equivalents provide for significant civil and criminal penalties for non-permitted activities that result in harm to or harassmentposition, results of certain protected animals, including damage to their habitats. If such species are located in an area in which we conduct operations or if additional species in those areas become subject to protection, our operations and development projects, particularly transmission, generation and wind projects, could be restricted or delayed, or we could be required to implement expensive mitigation measures.

An effective system of internal control may not be maintained, leading to material weaknesses in internal control over financial reporting.

Section 404 of the Sarbanes-Oxley Act of 2002 requires management to make an assessment of the design and effectiveness of internal controls. During their assessment of these controls, management or our independent registered public accounting firm may identify areas of weakness in control design or effectiveness, which may lead to the conclusion that a material weakness in internal control exists. A control system, no matter how well designed and operated, can provide only reasonable, not absolute, assurance that the control system’s objectives will be met. Any control deficiencies we identify in thecash flows, future could adversely affect our ability to report our financial results on a timely and accurate basis, which could result in a loss of investor confidence in our financial reports or have a material adverse effect on our ability to operate our business or access sources of liquidity.



Threats of terrorism and catastrophic events that could result from terrorism, or individuals and/or groups attempting to disrupt our businesses, or the businesses of third parties, may impact our operations in unpredictable ways.

Terrorist acts or other similar events could harm our business by limiting its ability to generate, purchase or transmit power and by delaying the development and construction of new generating facilities and capital improvements to existing facilities. These events, and governmental actions in response, could result in a material decrease in revenues and significant additionalenvironmental compliance costs to repair and insure our assets and could adversely affect our operations by contributing to disruption of supplies and markets for natural gas, oil and other fuels. They could also impair our ability to raise capital by contributing to financial instability and lower economic activity.

The implementation of security guidelines and measures and maintenance of insurance, to the extent available, addressing such activities could increase costs. These types of events could materially adversely affect our financial results. In addition, these types of events could require significant management attention and resources and could adversely affect our reputation among customers and the public.

A cyber attack may disrupt our operations, or lead to a loss or misuse of confidential and proprietary information and create a potential liability.

We use and operate sophisticated information technology systems and network infrastructure. In addition, in the ordinary course of business, we collect and retain sensitive information including personal information about our customers and employees. Cyber attacks targeting our electronic control systems used at our generating facilities and for electric and gas distribution systems, could result in a full or partial disruption of our electric operations. Cyber attacks targeting other key information technology systems could further add to a full or partial disruption to our operations. Any disruption of these operations could result in a loss of service to customers and a significant decrease in revenues, as well as significant expense to repair system damage and remedy security breaches. Any theft, loss and/or fraudulent use of customer, shareowner, employee or proprietary data as a result of a cyber attack could subject us to significant litigation, liability and costs, as well as adversely impact our reputation with customers and regulators, among others.

We have instituted security measures and safeguards to protect our operational systems and information technology assets, including certain safeguards required by FERC. The security measures and safeguards we have implemented may not always be effective due to the evolving nature and sophistication of cyber attacks. Despite our implementation of security measures and safeguards, all of our information technology systems are vulnerable to disability, failures or unauthorized access, including cyber attacks. If our information technology systems were to fail or be breached by a cyber attack or a computer virus and be unable to be recovered in a timely way, we would be unable to fulfill critical business functions and sensitive confidential and other data could be compromised which could have a material adverse effect not only on our financial results, but on our public reputation as well.significant negative impact.


Market performance or changes in other assumptions could require us to make significant unplanned contributions to our pension plans and other postretirement benefit plans. Increasing costs associated with our defined benefit retirement plans may adversely affect our results of operations, financial position or liquidity.

We have a defined benefit pension plan that covers a substantial portion of our employees. Assumptions related to future costs, return on investments, interest rates and other actuarial assumptions have a significant impact on our funding requirements and the expense recognized related to these plans. These estimates and assumptions may change based on actual return on plan assets, changes in interest rates and changes in governmental regulations.



Increasing costs associated with our health care plans and other benefits may adversely affect our results of operations, financial position or liquidity.

The costs of providing health care benefits to our employees and retirees have increased substantially in recent years. We believe that our employee benefit costs, including costs related to health care plans for our employees and former employees, will continue to rise. Significant regulatory developments have, and likely will continue to, require changes to our current employee benefit plans and in our administrative and accounting processes, as well as changes to the cost of our plans, and the increasing costs and funding requirements associated with our health care plans may adversely affect our results of operations, financial position or liquidity.

Our electric utility rates are regulated on a state-by-state basis by the relevant state regulatory authorities based on an analysis of our costs, as reviewed and approved in a regulatory proceeding. Within our utility rates we have generally recovered the cost of providing employee benefits. As benefit costs continue to rise, there can be no assurance that the state public utility commissions will allow recovery.

ITEM 1B.    UNRESOLVED STAFF COMMENTS


None.


ITEM 3.LEGAL PROCEEDINGS


Information regarding our legal proceedings is incorporated herein by reference to the “Legal Proceedings” sub caption within Item 8, Note 1113, “Commitments and Contingencies,” of our Notes to the Financial Statements in this Annual Report on Form 10-K.




PART II


ITEM 5.MARKET FOR REGISTRANT’S COMMON EQUITY AND RELATED STOCKHOLDER
MATTERS


All of our common stock is held by our parent company, Black Hills Corporation. Accordingly, there is no established trading market for our common stock.


ITEM 7.MANAGEMENT’S DISCUSSION AND ANALYSIS OF RESULTS OF OPERATIONS


Our discussion and analysis for the year ended December 31, 2019 compared to 2018 is included herein. For discussion and analysis for the year ended December 31, 2018 compared to 2017, please refer to Item 7 of Part II, “Management’s Discussion and Analysis of Financial Condition and Results of Operations” in our Annual Report on Form 10-K for the year ended December 31, 2018, which was filed with the SEC on February 20, 2019.

All amounts are presented on a pre-tax basis unless otherwise indicated.

Significant Events


Name Rebranding2019 Overview


We now operate withOn September 17, 2019, South Dakota Electric completed construction on the trade name Black Hills Energy South Dakota. BHC rebranded allfinal 94-mile segment of its regulated utilities to operate under the name Black Hills Energy.

Regulatory Matters

During the first quarter of 2016, we commenced construction of the $54 million, 230-kV, 144 milea 175-mile electric transmission line that will connect the Teckla Substation in northeast Wyoming, to the Lange Substation nearfrom Rapid City, South Dakota.Dakota, to Stegall, Nebraska. The first 48-mile segment of thiswas placed in service on July 25, 2018, and the second 33-mile segment was placed in service on November 20, 2018.

In July 2019, South Dakota Electric and Wyoming Electric received approvals for the Renewable Ready program and jointly-filed CPCN to construct Corriedale. The wind project connecting Tecklawill be jointly owned by the two electric utilities to Osage, Wyoming was energized on August 31, 2016.deliver renewable energy for large commercial, industrial and governmental agency customers. In November 2019, South Dakota Electric received approval from SDPUC to increase the offering under the program by 12.5 MW to 32.5 MW. The second segment oftwo electric utilities also received a determination from the WPSC to increase the project to 52.5 MW. The $79 million project is expected to be placed in service in the first half of 2017.by year-end 2020.

On March 2, 2015, the SDPUC issued an order approving a rate stipulation and agreement authorizing an annual electric revenue increase for us of $6.9 million. The agreement was a Global Settlement and did not stipulate return on equity and capital structure. The SDPUC’s decision provides us a return on our investment in Cheyenne Prairie and associated infrastructure, and provides recovery of our share of operating expenses for this natural gas-fired facility. We implemented interim rates on October 1, 2014, coinciding with Cheyenne Prairie’s commercial operation date. Final rates were approved on April 1, 2015, effective October 1, 2014.


Non-GAAP Financial Measure


The following discussion includes financial information prepared in accordance with GAAP, as well as another financial measure, gross margin, that is considered a “non-GAAP financial measure.” Generally, a non-GAAP financial measure is a numerical measure of a company’s financial performance, financial position or cash flows that excludes (or includes) amounts that are included in (or excluded from) the most directly comparable measure calculated and presented in accordance with GAAP. Gross margin (revenue less cost of sales) is a non-GAAP financial measure due to the exclusion of depreciation from the measure. The presentation of gross margin is intended to supplement investors’ understanding of our operating performance.


In our Management’s Discussion and Analysis of Results of Operations, grossGross margin is calculated as operating revenue less cost of fuel and purchased power. Our gross margin is impacted by the fluctuations in power purchases and natural gas and other fuel supply costs. However, while these fluctuating costs impact gross margin as a percentage of revenue, they only impact total gross margin if the costs cannot be passed through to our customers.


Our gross margin measure may not be comparable to other companies’ gross margin measure. Furthermore, this measure is not intended to replace operating income as determined in accordance with GAAP as an indicator of operating performance.





Results of Operations

For the years ended December 31,2016Variance2015Variance2014
 (in thousands)
Revenue$267,632
$(10,232)$277,864
$9,376
$268,488
Fuel and purchased power75,026
(8,313)83,339
(10,637)93,976
Gross margin192,606
(1,919)194,525
20,013
174,512
      
Operating expenses107,026
415
106,611
1,213
105,398
Operating income85,580
(2,334)87,914
18,800
69,114
      
Interest expense, net(20,192)982
(21,174)(1,472)(19,702)
Other income, net2,278
1,244
1,034
372
662
Income tax expense(22,528)72
(22,600)(6,088)(16,512)
Net income$45,138
$(36)$45,174
$11,612
$33,562

The following tables provide certain electric utility operating statistics for the years ended December 31 (dollars inOperating results were as follows (in thousands):
Revenue
Customer Base2016Percentage Change2015Percentage Change2014
Residential$72,084
(1)%$72,659
4 %$69,712
Commercial97,579
(3)%100,511
9 %91,882
Industrial33,409
 %33,336
17 %28,451
Municipal3,705
2 %3,626
6 %3,409
Total retail sales206,777
(2)%210,132
9 %193,454
Contract wholesale17,037
(3)%17,537
(17)%21,206
Wholesale off-system15,431
(34)%23,241
(17)%28,002
Total electric sales239,245
(5)%250,910
3 %242,662
Other revenue28,387
5 %26,954
4 %25,826
Total revenue$267,632
(4)%$277,864
3 %$268,488
For the years ended December 31,2019Variance2018Variance2017
  
Revenue (a)
$291,219
$(6,861)$298,080
$9,647
$288,433
Fuel and purchased power (a)
73,115
(19,771)92,886
5,248
87,638
Gross margin (non-GAAP)218,104
12,910
205,194
4,399
200,795
  
 
 
Operations and maintenance134,167
7,308
126,859
9,890
116,969
Operating income83,937
5,602
$78,335
(5,491)83,826
  
 
 
Interest expense, net(21,718)(370)(21,348)(968)(20,380)
Other income (expense), net(5,816)(5,146)(670)(2,650)1,980
Income tax expense(9,501)1,171
(10,672)3,456
(14,128)
Net income$46,902
$1,257
$45,645
$(5,653)$51,298


(a)2019 revenue and purchased power, as well as associated quantities, for a certain wholesale contract have been presented on a net basis. This resulted in a decrease of $12 million to both 2019 revenue and fuel and purchased power.  Prior year amounts were presented on a gross basis and, due to their immaterial nature, were not revised.  This 2019 presentation change has no impact on Gross margin.

2019 Compared to 2018

Gross margin increased primarily due to $6.5 million of reduced purchased power capacity charges, $3.4 million of increased rider revenues from new investments and $3.1 million of increased commercial and industrial demand.

Operations and maintenance expense increased primarily due to higher employee costs and outside services expenses.
Other income (expense), net. For the year ended December 31, 2019, we expensed $5.4 million of development costs related to projects we no longer intend to construct.

Income tax expense decreased primarily due to tax benefits for excess deferred tax amortization related to tax reform.

MWh Sold
Customer Base2016Percentage Change2015Percentage Change2014
Residential520,798
 %521,828
(4)%542,008
Commercial783,319
(1)%792,466
1 %782,238
Industrial429,912
 %429,140
7 %399,648
Municipal33,591
5 %31,924
 %32,076
Total retail sales1,767,620
 %1,775,358
1 %1,755,970
Contract wholesale246,630
(5)%260,893
(23)%340,871
Wholesale off-system (a)
597,695
(29)%837,120
4 %808,257
Total electric sales2,611,945
(9)%2,873,371
(1)%2,905,098
Losses and company use155,370
(7)%167,332
(6)%177,577
Total energy2,767,315
(9)%3,040,703
(1)%3,082,675
 For the year ended December 31,
Contracted power plant fleet availability (a)201920182017
Coal-fired plants (b)
91.0%92.7%86.0%
Other plants (c)
85.0%96.8%96.4%
Total availability87.8%94.9%91.6%
_________________________
(a)Decrease in 2016Availability is driven by weaker market conditions

We own approximately 445 MW of electric utility generating capacity and purchase an additional 50 MW under a long-term agreement expiring in 2023. On March 21, 2014, we retired the Ben French, Neil Simpson I, and Osage coal-fired power plants. These three plants totaling 81 MW were closed because of federal environmental regulations. On October 1, 2014, we transferred the remaining net book value of these retired plants to a regulatory asset in accordance with an order granted by the SDPUC. These plants are primarily replaced by our share of Cheyenne Prairie.



Regulated Power Plant Fleet Availability201620152014
Coal-fired plants86.5%
(a) 
91.1%91.8% 
Other plants98.0% 96.0%91.5%
(b) 
Total availability93.0% 93.9%91.6% 
_________________________
(a)2016 reflects planned and unplanned outages.calculated using a weighted average based on capacity of our generating fleet.
(b)2014 reflects scheduled outages.2019 included planned outages at Neil Simpson II and Wygen III and unplanned outages at Wyodak Plant and Wygen III.
Resources2016Percentage Change2015Percentage Change2014
MWh generated:     
Coal1,467,403
(5)%1,537,744
(3)%1,591,061
Gas118,467
46 %80,944
80 %44,984
 1,585,870
(2)%1,618,688
(1)%1,636,045
      
MWh purchased1,181,445
(17)%1,422,015
(2)%1,446,630
Total resources2,767,315
(9)%3,040,703
(1)%3,082,675

Heating and Cooling Degree Days201620152014
Actual   
Heating degree days6,402
6,521
7,373
Cooling degree days646
577
481
    
Variance from 30-year average (a)
   
Heating degree days(10)%(8)%4 %
Cooling degree days(4)%(14)%(28)%
______________
(a)(c)30-year average is from NOAA Climate Normals2019 included planned outages at Neil Simpson CT and Lange CT.


2016 Compared to 2015

Gross margin decreased primarily due to a prior year return on invested capital of $1.2 million from a rate case, and a $1.3 million decrease due to third party billing true-ups related to the current and prior years, partially offset by the weather impact from the increase in cooling degree days compared to the same period in the prior year.

Operations and maintenance increased primarily due to higher depreciation expense driven by additional plant in service compared to the same period in the prior year, partially offset by lower employee costs driven by a change in operating expense allocations impacting us as a result of our Parent Company integrating the acquired SourceGas utilities.

Interest expense, net decreased primarily due to higher AFUDC income in the current year driven by higher construction work-in-process balances compared to the same period in the prior year.

Other income, net was comparable to the prior year.

Income tax expense: The 2016 effective tax rate is comparable to the prior year.



2015 Compared to 2014

Gross margin increased primarily due to a return on capital investments in Cheyenne Prairie which increased gross margins by $11.9 million and increased energy cost recoveries by $2.7 million. Retail margins increased $4.7 million primarily due to commercial and industrial load increases from higher MWh sold. These increases are partially offset by an approximately $1.7 million decrease in residential margins driven primarily by a 12% decrease in heating degree days compared to the same period in the prior year.

Operations and maintenance increased reflecting an increase in depreciation expense primarily due to a higher asset base and amortization of regulatory plant decommissioning costs.

Interest expense, net increased primarily due to interest costs from the $85 million of permanent financing put in place during the fourth quarter of 2014 for Cheyenne Prairie.

Other income, net was comparable to the prior year.

Income tax expense: The 2015 effective tax rate is comparable to the prior year.

Credit Ratings


Credit ratings impact our ability to obtain short and long-term financing, the cost of such financing, and vendor payment terms, including collateral requirements. The following table represents our credit rating from each agency’s review which were in effect at December 31, 2016:2019:


Rating AgencySenior Secured Rating
S&P(a)
A-A
Moody’s(b)
A1
Fitch(c)
A

__________
(a)On April 30, 2019, S&P affirmed A rating.
(b)On December 20, 2019, Moody’s affirmed A1 rating.
(c)On August 29, 2019, Fitch affirmed A rating.


Critical Accounting Policies Involving Significant Accounting Estimates


We prepare our financial statements in conformity with GAAP. In many cases, the accounting treatment of a particular transaction is specifically dictated by GAAP and does not require management’s judgment in application. There are also areas which require management’s judgment in selecting among available GAAP alternatives. We are required to make certain estimates, judgments and assumptions that we believe are reasonable based upon the information available. These estimates and assumptions affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the periods presented. Actual results may differ from our estimates and to the extent there are material differences between these estimates, judgments or assumptions and actual results, our financial statements will be affected. We believe the following accounting estimates are the most critical in understanding and evaluating our reported financial results.


The following discussion of our critical accounting estimates should be read in conjunction with Note 1, “Business Description and Summary of Significant Accounting Policies” of the Notes to Financial Statements in this Annual Report on Form 10-K.

Pension and Other Postretirement Benefits

The Company, as described in Note 8 of the Financial Statements in this Annual Report on Form 10-K, has a defined benefit pension plan, a post-retirement healthcare plan and a non-qualified retirement plan. A Master Trust was established for the investment of assets of the defined benefit pension plan.10-K.

Accounting for pension and other postretirement benefit obligations involves numerous assumptions, the most significant of which relate to the discount rates, health care cost trend rates, expected return on plan assets, compensation increases, retirement rates and mortality rates. The determination of our obligation and expenses for pension and other postretirement benefits is dependent on the assumptions determined by management and used by actuaries in calculating the amounts. Although we believe our assumptions are appropriate, significant differences in our actual experience or significant changes in our assumptions may materially affect our pension and other postretirement obligations and our future expense.



The pension benefit cost for 2017 for our non-contributory funded pension plan is expected to be approximately $0.6 million compared to $1.5 million in 2016. The decrease in pension benefit cost is driven by the merging of three of Black Hills Corporation’s defined benefit pension plans into one, improved mortality rates and better than expected return on plan assets partially offset by a decrease in the discount rate.

Beginning in 2016, the Company changed the method used to estimate the service and interest cost components of the net periodic pension, supplemental non-qualified defined benefit and other postretirement benefit costs. The new method used the spot yield curve approach to estimate the service and interest costs by applying the specific spot rates along the yield curve used to determine the benefit obligations to relevant projected cash outflows. Prior to 2016, the service and interest costs were determined using a single weighted-average discount rate based on hypothetical AA Above Median yield curves used to measure the benefit obligation at the beginning of the period. The change does not affect the measurement of the total benefit obligations as the change in service and interest costs offsets the actuarial gains and losses recorded in other comprehensive income.

The Company changed to the new method to provide a more precise measure of service and interest costs by improving the correlation between the projected benefit cash flows and the discrete spot yield curve rates. The Company accounted for this change as a change in estimate prospectively beginning in 2016.

The effect of hypothetical changes to selected assumptions on the pension and other postretirement benefit plans would be as follows in thousands of dollars:
AssumptionsPercentage Change
December 31, 2016
Increase/(Decrease)
PBO/APBO (a)
2017
 Increase/(Decrease) Expense - Pretax
Pension
Discount rate (b)
 +/- 0.5(3,658)/4,020(854)/803
Expected return on assets +/- 0.5N/A(266)/266
OPEB
Discount rate (b)
 +/- 0.5(211)/22511/(12)
Expected return on assets +/- 0.5N/AN/A
Health care cost trend rate (b)
 +/- 1.0125/(121)5/(5)
__________________________
(a)Projected benefit obligation for pension plans and accumulated postretirement benefit obligation (APBO) for OPEB plans.
(b)Impact on service cost, interest cost and amortization of gains or losses.


Regulation


Our utility operations are subject to cost-of-service regulation with respectand earnings oversight from federal and state utility commissions. This regulatory treatment does not provide any assurance as to achievement of desired earnings levels. Our retail electric rates service area, accounting,are regulated on a state-by-state basis by the relevant state regulatory commissions based on an analysis of our costs, as reviewed and various other matters by stateapproved in a regulatory proceeding. The rates that we are allowed to charge may or may not match our related costs and federal regulatory authorities. The accounting regulations provide that rate-regulated public utilities account and report assets and liabilities consistent with the economic effects of the manner in which independent third-party regulators establish rates. Regulatory assets generally represent incurred or accrued costs that have been deferred when future recovery from customers is probable. Regulatory liabilities generally represent amounts that are expected to be refunded to customers in future rates or amounts collected in current rates for future costs.allowed return on invested capital at any given time.


Management continually assesses the probability of future recoveries and obligations associated with regulatory assets and future obligations associated with liabilities. Factors such as the current regulatory environment, recently issued rate orders, and historical precedents are considered. As a result, we believe that the accounting prescribed under rate-based regulation remains appropriate and our regulatory assets are probable for recovery in current rates or in future rate proceedings.



To some degree, we are permitted to recover certain costs (such as increased fuel and purchased power costs) without having to file a rate review. To the extent we are able to pass through such costs to our customers, and a state public utility commission subsequently determines that such costs should not have been paid by the customers, we may be required to refund such costs. Any such costs not recovered through rates, or any such refund, could adversely affect our results of operations, financial position or cash flows.


Unbilled RevenueAs of December 31, 2019 and 2018, we had total regulatory assets of $76 million and $76 million respectively, and total regulatory liabilities of $166 million and $163 million respectively. See Note 7 of the Notes to the Financial Statements for further information.


Revenues attributable to energy delivered to customers, but not yet billed under the cycle billing method, are estimated and accrued and the related costs are charged to expense. Factors influencing the determination of unbilled revenues may include estimates of delivered sales volumes based on weather information and customer consumption trends.


Income Taxes


We file a federal income tax return with other members of the Parent consolidated group. For financial statementEach tax-paying entity records income taxes as if it were a separate taxpayer for both federal and state income tax purposes federal income taxesand consolidating adjustments are allocated to the individual companiessubsidiaries based on amounts calculated on a separate return basis.company computations of taxable income or loss.


We use the asset and liability method ofin accounting for income taxes. Under thisthe asset and liability method, deferred income taxes are recognized at currently enacted income tax rates, to reflect the tax effect of temporary differences between the financial and tax basis of assets and liabilities as well as net operating loss and tax credit carryforwards. Such temporary differences are the result of provisions in the income tax law that either require or permit certain items to be reported on the income tax return in a different period than they are reported in the financial statements.


As of December 31, 2019, we have a regulatory liability associated with TCJA related items of $98 million, completing our accounting for the revaluation of deferred taxes pursuant to the TCJA. A significant portion of the excess deferred taxes are subject to the average rate assumption method, as prescribed by the IRS, and will generally be amortized as a reduction of customer rates over the remaining lives of the related assets.

As of December 31, 2019, the Company has amortized $3.1 million of regulatory liability associated with TCJA related items. The portion that was eligible for amortization under the average rate assumption method in 2019, but is awaiting resolution of the treatment of these amounts in future regulatory proceedings, has not been recognized and may be refunded in customer rates at any time in accordance with the resolution of pending or future regulatory proceedings.
In assessing the realization of deferred tax assets, management considers whether it is more likely than not that some portion or all of the deferred tax assets will not be realized and provides any necessary valuation allowances as required. If we determine that we will be unable to realize all or part of our deferred tax assets in the future, an adjustment to the deferred tax asset would be charged to income in the period such determination was made. Although we believe our assumptions, judgments and estimates are reasonable, changes in tax laws or our interpretations of tax laws and the resolution of current and any future tax audits could significantly impact the amounts provided for income taxes in our financial statements.


See Note 69 of the Notes to the Financial Statements in this Annual Report on Form 10-K for additional information.

Pension and Other Postretirement Benefits

As described in Note 12 of the Financial Statements in this Annual Report on Form 10-K, we have a defined benefit pension plan, a post-retirement healthcare plan and non-qualified retirement plans. A Master Trust was established for the investment of assets of the defined benefit pension plan.

Accounting for pension and other postretirement benefit obligations involves numerous assumptions, the most significant of which relate to the discount rates, health care cost trend rates, expected return on plan assets, compensation increases, retirement rates and mortality rates. The determination of our obligation and expenses for pension and other postretirement benefits is dependent on the assumptions determined by management and used by actuaries in calculating the amounts. Although we believe our assumptions are appropriate, significant differences in our actual experience or significant changes in our assumptions may materially affect our pension and other postretirement obligations and our future expense.

The 2020 pension benefit cost for our non-contributory funded pension plan is expected to be $2.1 million compared to $0.6 million in 2019. The increase in pension benefit cost is driven primarily by a decrease in the discount rate and lower expected return on assets.


The effect of hypothetical changes to selected assumptions on the pension and other postretirement benefit plans would be as follows in thousands of dollars:
December 31,
AssumptionsPercentage Change
2019
Increase/(Decrease)
PBO/APBO (a)
2020
 Increase/(Decrease) Expense - Pretax
Pension
Discount rate (b)
 +/- 0.5(3,879)/4,270(703)/709
Expected return on assets +/- 0.5N/A(282)/282
OPEB
Discount rate (b)
 +/- 0.5(225)/2459/(10)
Expected return on assets +/- 0.5N/AN/A
__________________________
(a)Projected benefit obligation (PBO) for pension plans and accumulated postretirement benefit obligation (APBO) for OPEB plans.
(b)Impact on service cost, interest cost and amortization of gains or losses.


New Accounting Pronouncements

See Note 1 of our Notes to the Financial Statements in this Annual Report on Form 10-K for information on new accounting standards adopted in 2019 or pending adoption.







ITEM 8.FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA


INDEX TO FINANCIAL STATEMENTS







Management’s Report on Internal Control over Financial Reporting


Management of Black Hills Power isWe are responsible for establishing and maintaining adequate internal control over financial reporting as defined in Rules 13a-15(f) and 15d-15(f) under the Securities Exchange Act of 1934, as amended. Our internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles.


All internal control systems, no matter how well designed, have inherent limitations. Therefore, even those systems determined to be effective can provide only reasonable assurance with respect to financial statement preparation and presentation. Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.
Under the supervision and with the participation of management, including our Chief Executive Officer and Chief Financial Officer, we conducted an evaluation of the effectiveness of our internal control over financial reporting as of December 31, 2016,2019, based on the criteria set forth in Internal Control - Integrated Framework (2013)issued by the Committee of Sponsoring Organizations of the Treadway Commission. This evaluation included review of the documentation of controls, evaluation of the design effectiveness of controls, testing of the operating effectiveness of controls and a conclusion on this evaluation. Based on our evaluation, we have concluded that our internal control over financial reporting was effective as of December 31, 20162019.


This annual report does not include an attestation report of our registered public accounting firm regarding internal control over financial reporting because this requirement is inapplicable to companies such as ours which are known as non-accelerated filers.


Black Hills Power







REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM


To the stockholder and the Board of Directors and Stockholder of
Black Hills Power, Inc.
Rapid City, South Dakota

Opinion on the Financial Statements

We have audited the accompanying balance sheets of Black Hills Power, Inc. (the “Company”"Company") as of December 31, 20162019 and 2015, and2018, the related statements of income, comprehensive income, (loss), common stockholder’s equity, and cash flows, for each of the three years in the period ended December 31, 2016. Our audits also included2019, and the financial statementrelated notes and the schedule listed in the Index at Item 15. 15 (collectively referred to as the “financial statements”). In our opinion, the financial statements present fairly, in all material respects, the financial position of the Company as of December 31, 2019 and 2018, and the results of its operations and its cash flows for each of the three years in the period ended December 31, 2019, in conformity with accounting principles generally accepted in the United States of America.

Basis for Opinion

These financial statements and financial statement schedule are the responsibility of the Company’sCompany's management. Our responsibility is to express an opinion on the Company's financial statements and financial statement schedule based on our audits. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.


We conducted our audits in accordance with the standards of the Public Company Accounting Oversight Board (United States)PCAOB and in accordance with auditing standards generally accepted in the United States of America. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement.misstatement, whether due to error or fraud. The Company is not required to have, nor were we engaged to perform, an audit of its internal control over financial reporting. OurAs part of our audits, included considerationwe are required to obtain an understanding of internal control over financial reporting as a basis for designing audit procedures that are appropriate in the circumstances, but not for the purpose of expressing an opinion on the effectiveness of the Company’s internal control over financial reporting. Accordingly, we express no such opinion. An audit also includes

Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence supportingregarding the amounts and disclosures in the financial statements, assessingstatements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statement presentation.statements. We believe that our audits provide a reasonable basis for our opinion.

In our opinion, such financial statements present fairly, in all material respects, the financial position of Black Hills Power, Inc. as of December 31, 2016 and 2015, and the results of their operations and their cash flows for each of the three years in the period ended December 31, 2016, in conformity with accounting principles generally accepted in the United States of America. Also, in our opinion, such financial statement schedule, when considered in relation to the basic financial statements taken as a whole, presents fairly in all material respects the information set forth therein.


/s/ DELOITTE & TOUCHE LLP

Minneapolis, Minnesota
February 28, 201718, 2020



We have served as the Company’s auditor since 2002.


BLACK HILLS POWER, INC.
STATEMENTS OF INCOME


Years ended December 31,201620152014201920182017
(in thousands)(in thousands)
  
Revenue$267,632
$277,864
$268,488
$291,219
$298,080
$288,433
  
Operating expenses:  
Fuel and purchased power75,026
83,339
93,976
73,115
92,886
87,638
Operations and maintenance66,384
68,088
70,356
84,661
79,523
74,064
Depreciation and amortization34,030
32,552
29,100
41,322
39,649
35,862
Taxes - property6,612
5,971
5,942
8,184
7,687
7,043
Total operating expenses182,052
189,950
199,374
207,282
219,745
204,607
  
Operating income85,580
87,914
69,114
83,937
78,335
83,826
  
Other income (expense):  
Interest expense(22,908)(22,337)(20,569)(23,972)(22,545)(22,421)
AFUDC - borrowed1,140
506
248
1,437
521
1,137
Interest income1,576
657
619
817
676
904
AFUDC - equity2,165
918
519

221
2,165
Other expense(185)(117)(105)
Other income298
233
248
Other income (expense), net(5,816)(891)(185)
Total other income (expense)(17,914)(20,140)(19,040)(27,534)(22,018)(18,400)
  
Income before income taxes67,666
67,774
50,074
56,403
56,317
65,426
Income tax expense(22,528)(22,600)(16,512)(9,501)(10,672)(14,128)
  
Net income$45,138
$45,174
$33,562
$46,902
$45,645
$51,298



The accompanying notesNotes to financial statementsthe Financial Statements are an integral part of these financial statements.Financial Statements.





BLACK HILLS POWER, INC.
STATEMENTS OF COMPREHENSIVE INCOME (LOSS)


Years ended December 31,201620152014
 (in thousands)
    
Net income$45,138
$45,174
$33,562
    
Other comprehensive income (loss), net of tax:   
Benefit plan liability adjustments - net gain (loss) (net of tax of $27, $(36) and $189, respectively)(50)68
(351)
Reclassification adjustment of benefit plan liability - net gain (loss) (net of tax of $(29), $(33) and $(16), respectively)53
61
29
Reclassification adjustment of cash flow hedges settled and included in net income (loss) (net of tax of $(22), $319 and $(364), respectively)42
383
(300)
Other comprehensive income (loss), net of tax45
512
(622)
    
Comprehensive income (loss), net of tax$45,183
$45,686
$32,940
Years ended December 31,201920182017
 (in thousands)
    
Net income$46,902
$45,645
$51,298
    
Other comprehensive income (loss):   
Benefit plan liability adjustments - net gain (loss) (net of tax of $83, $(62), and $50 respectively)(312)235
(94)
Benefit plan liability adjustments - prior service costs (net of tax of $2, $0 and $0, respectively)(8)

Reclassification adjustment of benefit plan liability - net (gain) loss (net of tax of $(166), $(22), and $(30), respectively)(101)81
56
Derivative instruments designated as cash flow hedges:   
Reclassification of net realized (gains) losses on settled/amortized interest rate swaps (net of tax of $(132), $(13), and $(22), respectively)(68)51
42
Other comprehensive income (loss), net of tax(489)367
4
    
Comprehensive income$46,413
$46,012
$51,302



See Note 710 for additional disclosure related to comprehensive income.


The accompanying notesNotes to financial statementsthe Financial Statements are an integral part of these financial statements.

Financial Statements.

BLACK HILLS POWER, INC.
BALANCE SHEETS

As of December 31,2016201520192018
(in thousands, except share amounts)(in thousands, except share amounts)
ASSETS  
Current assets:  
Cash and cash equivalents$234
$297
Receivables - customers, net30,614
27,856
Receivables - affiliates9,526
6,734
Other receivables, net351
236
Money pool notes receivable28,409
76,813
Cash$6
$112
Accounts receivable, net25,532
28,431
Accounts receivable from affiliates7,838
8,119
Materials, supplies and fuel22,389
24,282
27,950
24,853
Regulatory assets, current18,119
14,096
21,588
19,052
Other current assets3,876
43,118
4,949
4,538
Total current assets113,518
193,432
87,863
85,105
  
Investments4,841
4,725
5,079
4,889
  
Property, plant and equipment1,236,387
1,166,126
1,494,670
1,381,045
Less accumulated depreciation and amortization(338,828)(326,074)
Less: accumulated depreciation and amortization(400,054)(376,160)
Total property, plant and equipment, net897,559
840,052
1,094,616
1,004,885
  
Other assets:  
Regulatory assets, non-current74,015
71,717
54,109
56,680
Other, non-current assets3,816
152
Total other assets77,831
71,869
Other assets, non-current18,690
9,729
Total other assets, non-current72,799
66,409
TOTAL ASSETS$1,093,749
$1,110,078
$1,260,357
$1,161,288


The accompanying notesNotes to financial statementsthe Financial Statements are an integral part of these financial statements.Financial Statements.




BLACK HILLS POWER, INC.
BALANCE SHEETS
(Continued)


As of December 31,2016201520192018
(in thousands, except share amounts)(in thousands, except share amounts)
LIABILITIES AND STOCKHOLDER’S EQUITY  
Current liabilities:  
Accounts payable$14,158
$14,472
$20,654
$25,122
Accounts payable - affiliates31,799
30,582
Accounts payable to affiliates32,121
25,804
Accrued liabilities37,436
69,454
25,492
34,193
Money pool notes payable57,585
38,690
Notes payable to Parent25,000

Regulatory liabilities, current84

3,162
2,574
Total current liabilities83,477
114,508
164,014
126,383
  
Long-term debt339,756
339,616
340,176
340,035
  
Deferred credits and other liabilities:  
Deferred income tax liabilities, net211,443
188,961
112,202
114,009
Regulatory liabilities, non-current53,866
51,583
163,009
160,642
Benefit plan liabilities19,544
20,033
14,636
14,606
Other, non-current liabilities1,001
3,398
15,397
1,368
Total deferred credits and other liabilities285,854
263,975
305,244
290,625
  
Commitments and contingencies (Notes 4, 8, 9 and 11)
Commitments and contingencies (Notes 5, 12, 13 and 14)

  
Stockholder’s equity:  
Common stock $1 par value; 50,000,000 shares authorized; 23,416,396 shares issued23,416
23,416
23,416
23,416
Additional paid-in capital39,575
39,575
39,575
39,575
Retained earnings322,933
330,295
389,312
342,145
Accumulated other comprehensive loss(1,262)(1,307)
Accumulated other comprehensive income (loss)(1,380)(891)
Total stockholder’s equity384,662
391,979
450,923
404,245
TOTAL LIABILITIES AND STOCKHOLDER’S EQUITY$1,093,749
$1,110,078
$1,260,357
$1,161,288


The accompanying notesNotes to financial statementsthe Financial Statements are an integral part of these financial statements.

Financial Statements.

BLACK HILLS POWER, INC.
STATEMENTS OF CASH FLOWS


Years ended December 31,201620152014201920182017
(in thousands)(in thousands)
Operating activities:  
Net income$45,138
$45,174
$33,562
$46,902
$45,645
$51,298
Adjustments to reconcile net income to net cash provided by operating activities -  
Depreciation and amortization34,030
32,552
29,100
41,322
39,649
35,862
Deferred income taxes20,690
7,690
16,518
(4,281)5,218
1,004
AFUDC - equity(2,165)(918)(519)
Employee benefits1,770
2,403
1,295
778
1,518
817
Other adjustments391
232
(2,330)9,325
2,555
264
Change in operating assets and liabilities -  
Accounts receivable and other current assets(3,963)(3,223)(10,412)(933)(3,576)3,287
Accounts payable and other current liabilities6,175
20,455
7,210
(9,881)(5,648)(7,254)
Contributions to defined benefit pension plan(820)
(1,696)
Regulatory assets(4,023)(3,839)(5,366)(3,290)27
978
Regulatory liabilities
(2,479)2,479
639
2,561

Contributions to defined benefit pension plan(1,753)(1,795)(4,000)
Other operating activities(8,339)(5,680)(6,624)(1,089)(1,407)(1,853)
Net cash provided by operating activities88,884
92,367
63,217
77,739
84,747
80,403
  
Investing activities:  
Property, plant and equipment additions(84,750)(56,795)(82,826)(122,833)(73,456)(79,566)
Notes receivable from affiliate companies, net(4,095)(36,687)(51,334)
Other investing activities(102)(128)(154)1,093
(488)(861)
Net cash (used in) investing activities(88,947)(93,610)(134,314)(121,740)(73,944)(80,427)
  
Financing activities:  
Long-term debt - repayments

(12,200)
Long-term debt - issuance

85,000
Other financing activities
(2)(961)
Change in money pool notes payable, net18,895
(10,707)(194)
Notes payable to parent25,000


Net cash provided by (used in) financing activities
(2)71,839
43,895
(10,707)(194)
  
Net change in cash and cash equivalents(63)(1,245)742
Net change in cash(106)96
(218)
  
Cash and cash equivalents: 
Beginning of year297
1,542
800
End of year$234
$297
$1,542
Cash beginning of year112
16
234
Cash end of year$6
$112
$16


See Note 1011 for Supplemental Cash Flows information.


The accompanying notesNotes to financial statementsthe Financial Statements are an integral part of these financial statements.

Financial Statements.

BLACK HILLS POWER, INC.
STATEMENTS OF COMMON STOCKHOLDER’S EQUITY


201620152014201920182017
(in thousands)(in thousands)
Common stock shares:  
Balance beginning of year23,416
23,416
23,416
23,416
23,416
23,416
Issuance of common stock





Balance end of year23,416
23,416
23,416
23,416
23,416
23,416
  
Common stock amounts:  
Balance beginning of year$23,416
$23,416
$23,416
$23,416
$23,416
$23,416
Issuance of common stock





Balance end of year$23,416
$23,416
$23,416
$23,416
$23,416
$23,416
  
Additional paid-in capital:  
Balance beginning of year$39,575
$39,575
$39,575
$39,575
$39,575
$39,575
Issuance of common stock





Balance end of year$39,575
$39,575
$39,575
$39,575
$39,575
$39,575
  
Retained earnings:  
Balance beginning of year$330,295
$313,622
$280,060
$342,145
$332,499
$322,933
Net income45,138
45,174
33,562
46,902
45,645
51,298
Non-cash dividend to Parent company(52,500)(28,501)

(36,000)(42,000)
Implementation of ASU 2016-02 Leases(7)

Other272
1
268
Balance end of year$322,933
$330,295
$313,622
$389,312
$342,145
$332,499
  
Accumulated other comprehensive loss:  
Balance beginning of year$(1,307)$(1,819)$(1,197)$(891)$(1,258)$(1,262)
Other comprehensive (loss) income, net of tax45
512
(622)(489)367
4
Balance end of year$(1,262)$(1,307)$(1,819)$(1,380)$(891)$(1,258)
  
Total stockholder’s equity$384,662
$391,979
$374,794
$450,923
$404,245
$394,232


The accompanying notesNotes to financial statementsthe Financial Statements are an integral part of these financial statements.

Financial Statements.

NOTES TO THE FINANCIAL STATEMENTS
December 31, 2016, 20152019, 2018 and 20142017



(1)    BUSINESS DESCRIPTION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES


Business Description


Black Hills Power, Inc., doing business as Black Hills Energy - (“South Dakota (the Company,Electric,” the “Company,” “we,” “us”“us,” or “our”), is a regulated electric utility serving customers in Montana, South Dakota Wyoming and Montana.Wyoming. We are a wholly-owned subsidiary of BHC, or the Parent, a public registrant listed on the New York Stock Exchange.


Basis of Presentation


The financial statements include the accounts of Black Hills Power, Inc.South Dakota Electric and also our ownership interests in the assets, liabilities and expenses of our jointly owned facilities (Note 3(Note 4) and are prepared in accordance with GAAP.

Revisions

Certain revisions have been made to prior years’ financial information to conform to the current year presentation.

We revised our presentation of cash and book overdrafts and certain cash transactions processed on behalf of affiliates.  For accounts with the same financial institution where there is a banking arrangement that clears payments with balances in other bank accounts, book overdrafts are presented on a combined basis by bank as cash and cash equivalents. Cash collected or disbursed on behalf of affiliates is presented as Receivables - affiliates or Accounts Payable - affiliates. Prior year amounts were corrected to conform to the current year presentation, which decreased cash and cash equivalents by $7.3 million, $5.1 million and $1.5 million as of December 31, 2015, December 31, 2014 and December 31, 2013, respectively; increased Receivables - affiliates by $1.0 million, increased Accounts payable - affiliates by $0.6 million and decreased Accounts payable by $6.9 million as of December 31, 2015. It also decreased net cash flows provided by operations by $2.2 million and $3.6 million for the years ended December 31, 2015 and 2014 respectively. We assessed the materiality of these changes, taking into account quantitative and qualitative factors, and determined them to be immaterial to the balance sheet as of December 31, 2015 and to the statements of cash flows for the years ended December 31, 2015 and 2014. There is no impact to the Statements of Income, Statements of Comprehensive Income (Loss) or Statements of Common Stockholder’s Equity for any period reported.


Use of Estimates and Basis of Presentation


The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of certain assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. ActualChanges in facts and circumstances or additional information may result in revised estimates and actual results could differ materially from those estimates.


Cash and Cash Equivalents


We consider all highly liquid investments with an original maturity of three months or less to be cash and cash equivalents. As of December 31, 2019 and 2018, we have 0 cash equivalents.

Accounts Receivable and Allowance for Doubtful Accounts

Accounts receivable consists of sales to residential, commercial, industrial, municipal and other customers all of which do not bear interest. These accounts receivable are stated at billed and unbilled amounts, net of write-offs or payment received.

We maintain an allowance for doubtful accounts which reflects our best estimate of uncollectible trade receivables. We regularly review our trade receivable allowances by considering such factors as historical experience, credit worthiness, the age of the receivable balances and current economic conditions that may affect collectibility.

In specific cases where we are aware of a customer’s inability or reluctance to pay, we record an allowance for doubtful accounts to reduce the net receivable balance to the amount we reasonably expect to collect. However, if circumstances change, our estimate of the recoverability of accounts receivable could be affected. Circumstances which could affect our estimates include, but are not limited to, customer credit issues, the level of commodity prices, customer deposits and general economic conditions. Accounts are written off once they are deemed to be uncollectible or the time allowed for dispute under the contract has expired.

Following is a summary of accounts receivable as of December 31 (in thousands):
 20192018
Accounts receivable, trade$14,778
$16,236
Unbilled revenue10,914
12,333
Less Allowance for doubtful accounts(160)(138)
Accounts receivable, net$25,532
$28,431



Changes to allowance for doubtful accounts for the years ended December 31, were as follows (in thousands):
 Balance at beginning of yearAdditions charged to costs and expensesDeductions charged to costs and expensesBalance at end of year
2019$138
$899
$(877)$160
2018$224
$911
$(997)$138
2017$157
$882
$(815)$224


Materials, Supplies and Fuel

Materials, supplies and fuel used for construction, operation and maintenance purposes are recorded using the weighted-average cost method.

Deferred Financing Costs

Deferred financing costs include loan origination fees, underwriter fees, legal fees and other costs directly attributable to the issuance of debt. Deferred financing costs are amortized over the estimated useful life of the related debt. These costs are presented on the balance sheet as an adjustment to the related debt liabilities.

Regulatory Accounting


Our regulated electric operations are subject to cost-of-service regulation by variousand earnings oversight from federal and state utility commissions. We account for income and federal agencies. The accounting policies followed are generally subject to the Uniform System of Accounts of FERC.

Our regulated utility operations followexpense items in accordance with accounting standards for regulated operationsoperations:

Certain costs, which would otherwise be charged to expense or OCI, are deferred as regulatory assets based on the expected ability to recover the costs in future rates.

Certain credits, which would otherwise be reflected as income or OCI, are deferred as regulatory liabilities based on the expectation the amounts will be returned to customers in future rates, or because the amounts were collected in rates prior to the costs being incurred

Management continually assesses the probability of future recoveries and obligations associated with regulatory assets and liabilities. Factors such as the current regulatory environment, recently issued rate orders, and historical precedents are considered. As a result, we believe that the accounting prescribed under rate-based regulation remains appropriate and our financial statements reflectregulatory assets are probable of recovery in current rates or in future rate proceedings.

If changes in the effects of the different rate making principles followed by the various jurisdictions regulating our electric operations. If rate recovery becomes unlikely or uncertain due to competition or regulatory action, these accounting standardsenvironment occur, we may no longer be eligible to apply this accounting treatment, and may be required to eliminate regulatory assets and liabilities from our balance sheet. Such changes could adversely affect our results of operations, financial position or cash flows.

As of December 31, 2019 and 2018, we had total regulatory assets of $76 million and $76 million respectively, and total regulatory liabilities of $166 million and $163 million respectively. See Note 7 for further information.

Property, Plant and Equipment

Additions to property, plant and equipment are recorded at cost. Included in the cost of regulated construction projects is AFUDC, when applicable, which represents the approximate composite cost of borrowed funds and a return on equity used to finance a regulated utility project.

The cost of regulated utility property, plant and equipment retired, or otherwise disposed of in the ordinary course of business, less salvage plus retirement costs, is charged to accumulated depreciation. Estimated removal costs associated with non-legal retirement obligations related to our regulated operations. Inelectric properties are reclassified from accumulated depreciation and reflected as regulatory liabilities. Ordinary repairs and maintenance of property, except as allowed under rate regulations, are charged to operations as incurred.

Property, plant and equipment is tested for impairment when it is determined that the carrying value of the assets may not be recoverable. A loss is recognized in the current period if it becomes probable that part of a cost of a plant under construction or recently completed plant will be disallowed for recovery from customers and a reasonable estimate of the disallowance can be made. For investments in property, plant and equipment that are abandoned and not expected to go into service, incurred costs and related deferred tax amounts are compared to the discounted estimated future rate recovery, and a loss is recognized, if necessary.

Depreciation provisions for regulated electric property, plant and equipment are computed on a straight-line basis using an annual composite rate of 2.2% in 2019, 2.3% in 2018 and 2.1% in 2017.

Accrued Liabilities

The following amounts by major classification are included in Accrued liabilities on the accompanying Balance Sheets as of December 31 (in thousands):
 20192018
Accrued employee compensation, benefits and withholdings$4,387
$4,206
Accrued property taxes6,685
6,332
Accrued income taxes1,946
12,536
Customer deposits and prepayments5,486
5,204
Accrued interest4,935
4,627
Other (none of which is individually significant)2,053
1,288
Total accrued liabilities$25,492
$34,193


Derivatives and Hedging Activities

Derivatives are measured at fair value and recognized as either assets or liabilities on the Balance Sheets, except for derivative contracts that qualify for and are elected under the normal purchase and normal sales exception. Normal purchases and normal sales are contracts where physical delivery is probable, quantities are expected to be used or sold in the normal course of business over a reasonable amount of time, and price is not tied to an unrelated underlying derivative.  Normal purchase and sales contracts are recognized when the underlying physical transaction is completed under the accrual basis of accounting. As part of our operations, we enter into contracts to buy and sell energy to meet the requirements of our customers.


From time to time we utilize risk management contracts including interest rate swaps to fix the interest on variable rate debt, or to lock in the Treasury yield component associated with anticipated issuance of senior notes.  For swaps that settled in connection with the issuance of senior debt, the effective portion is deferred as a component in AOCI and recognized as interest expense over the life of the senior note. As of December 31, 2019, we have no outstanding interest rate swap agreements.

We utilize master netting agreements which consist of an agreement between two parties who have multiple contracts with each other that provide for the net settlement of all contracts in the event we determineof default on or termination of any one contract. When the right of offset exists, accounting standards permit the netting of receivables and payables under a legally enforceable master netting agreement between counterparties. Accounting standards also permit offsetting of fair value amounts recognized for the right to reclaim, or the obligation to return, cash collateral against fair value amounts recognized for derivative instruments executed with the same counterparty. We reflect the offsetting of net derivative positions with fair value amounts for cash collateral with the same counterpart when a legal right of offset exists.

Fair Value Measurements

Financial Instruments

We use the following fair value hierarchy for determining inputs for our financial instruments. Our assets and liabilities for financial instruments are classified and disclosed in one of the following fair value categories:

Level 1 — Unadjusted quoted prices available in active markets that we no longer meetare accessible at the criteriameasurement date for followingidentical unrestricted assets or liabilities. Level 1 instruments primarily consist of highly liquid and actively traded financial instruments with quoted pricing information on an ongoing basis.

Level 2 — Pricing inputs include quoted prices for identical or similar assets and liabilities in active markets other than quoted prices in Level 1, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the asset or liability and inputs that are derived principally from or corroborated by observable market data by correlation or other means.

Level 3 — Pricing inputs are generally less observable from objective sources. These inputs reflect management’s best estimate of fair value using its own assumptions about the assumptions a market participant would use in pricing the asset or liability.

Assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. Our assessment of the significance of a particular input to the fair value measurement requires judgment and may affect the placement within the fair value hierarchy levels. We record transfers, if necessary, between levels at the end of the reporting period for all of our financial instruments.

Transfers into Level 3, if any, occur when significant inputs used to value the derivative instruments become less observable, such as a significant decrease in the frequency and volume in which the instrument is traded, negatively impacting the availability of observable pricing inputs. Transfers out of Level 3, if any, occur when the significant inputs become more observable, such as when the time between the valuation date and the delivery date of a transaction becomes shorter, positively impacting the availability of observable pricing inputs. We currently do not have any Level 3 investments.

Income Taxes

We file a federal income tax return with other members of the Parent’s consolidated group. For financial statement purposes, federal income taxes are allocated to the individual companies based on amounts calculated on a separate return basis.

The Company uses the asset and liability method in accounting for income taxes. Under the asset and liability method, deferred income taxes are recognized at currently enacted income tax rates, to reflect the tax effect of temporary differences between the financial and tax basis of assets and liabilities as well as operating loss and tax credit carryforwards. Such temporary differences are the result of provisions in the income tax law that either require or permit certain items to be reported on the income tax return in a different period than they are reported in the financial statements.

We use the deferral method of accounting for investment tax credits as allowed by our rate-regulated jurisdictions. Such a method results in the investment tax credit being amortized as a reduction to income tax expense over the estimated useful lives of the underlying property that gave rise to the credit.

We recognize interest income or interest expense and penalties related to income tax matters in Income tax expense on the Statements of Income.

We account for uncertainty in income taxes recognized in the financial statements in accordance with the accounting standards for regulated operations, the accounting impact to us could be an extraordinary non-cash charge to operationsincome taxes. The unrecognized tax benefit is classified in an amount that could be material.



Regulatory assets are includedOther, non-current liabilities or in Regulatory assets, current and Regulatory assets, non-currentDeferred income tax liabilities, net on the accompanying Balance Sheets. RegulatorySee Note 9 for additional information.

Recently Issued Accounting Standards

Simplifying the Accounting for Income Taxes, ASU 2019-12

In December 2019, the FASB issued ASU 2019-12, Simplifying the Accounting for Income Taxes as part of its overall simplification initiative to reduce costs and complexity in applying accounting standards while maintaining or improving the usefulness of the information provided to users of the financial statements. Amendments include removal of certain exceptions to the general principles of ASC 740, Income Taxes, and simplification in several other areas such as accounting for a franchise tax (or similar tax) that is partially based on income. The new guidance is effective for interim and annual periods beginning after December 15, 2020 with early adoption permitted. We are currently reviewing this standard to assess the impact on our financial position, results of operations and cash flows.

Internal-Use Software: Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract, ASU 2018-15

In August 2018, the FASB issued ASU 2018-15, Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract, which aligns the requirements for recording implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software. As a result, certain categories of implementation costs that previously would have been charged to expense as incurred are now capitalized as prepayments and amortized over the term of the arrangement. The new guidance is effective for annual periods beginning after December 15, 2019, and interim periods within those fiscal years. The new guidance can be applied either retrospectively or prospectively to all implementation costs incurred after the date of adoption. Early adoption is permitted. We adopted this standard prospectively on January 1, 2020. Adoption of this guidance did not have a material impact on our financial position, results of operations or cash flows.

Financial Instruments -- Credit Losses: Measurement of Credit Losses on Financial Instruments, ASU 2018-19

In June 2016, the FASB issued ASU 2016-13, Financial Instruments -- Credit Losses: Measurement of Credit Losses on Financial Instruments, which was subsequently amended by ASU 2018-19, ASU 2019-04, 2019-05, 2019-10, and 2019-11. The standard introduces new accounting guidance for credit losses on financial instruments within its scope, including trade receivables. This new guidance adds an impairment model that is based on expected losses rather than incurred losses. It is effective for interim and annual reporting periods beginning after December 15, 2019, with early adoption permitted.

We adopted this standard on January 1, 2020 with prior year comparative financial information remaining as previously reported when transitioning to the new standard. On January 1, 2020, we recorded an increase to our allowance for doubtful accounts, primarily associated with the inclusion of expected losses on unbilled revenue. Adoption of this standard did not have a material impact on our financial position, results of operations or cash flows.

Recently Adopted Accounting Standards

Leases, ASU 2016-02

In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842), to increase transparency and comparability among organizations by requiring the recognition of right-of-use assets and lease liabilities on the balance sheet for most leases, whereas previously only financing-type lease liabilities (capital leases) were recognized on the balance sheet. Under the new standard, disclosures are required to meet the objective of enabling users of financial statements to assess the amount, timing and uncertainty of cash flows arising from leases.


We adopted the standard effective January 1, 2019. We elected not to recast comparative periods coinciding with the new lease standard transition and will report these comparative periods as presented under previous lease guidance. In addition, we elected the package of practical expedients permitted under the transition guidance with the new standard, which among other things, allowed us to carry forward the historical lease classification. We also elected the practical expedient related to land easements, allowing us to carry forward our accounting treatment for existing land easements agreements.

Adoption of the new standard resulted in the recording of an operating lease right-of-use asset and off-setting obligation liability of $14 million, primarily for the Wygen III ground lease, as of January 1, 2019.

See Note 8 for additional details on leases.


(2)    REVENUE

Our revenue contracts generally provide for performance obligations that are fulfilled and transfer control to customers over time, represent a series of distinct services that are substantially the same, involve the same pattern of transfer to the customer, and provide a right to consideration from our customers in an amount that corresponds directly with the value to the customer for the performance completed to date. Therefore, we recognize revenue in the amount to which we have a right to invoice. Our primary types of revenue contracts are:

Regulated electric utility services tariffs - Our regulated operations, as defined by ASC 980, provide services to regulated customers under tariff rates, charges, terms and conditions of service, and prices determined by the jurisdictional regulators designated for our service territories. Our regulated services primarily encompass single performance obligations for delivery of commodity electricity and electric transmission services. These service revenues are variable based on quantities delivered, influenced by seasonal business and weather patterns. Tariffs are only permitted to be changed through a rate-setting process involving the state or federal regulatory commissions to establish contractual rates between the utility and its customers. All of our regulated utility sales are subject to regulatory-approved tariffs.

Power sales agreements - We have long-term wholesale power sales agreements with other load serving entities for the sale of excess power from owned generating units. In addition to these long-term contracts, the Company also sells excess energy to other load-serving entities on a short-term basis. The pricing for all of these arrangements is included in the executed contracts or confirmations, reflecting the standalone selling price, and is variable based on energy delivered.

The following table depicts the disaggregation of revenue, including intercompany revenue, from contracts with customers by customer type and timing of revenue recognition. Sales tax and other similar taxes are excluded from revenues.
 Year ended December 31, 2019Year ended December 31, 2018
 (in thousands)
Customer types:  
Retail$202,569
$197,184
Wholesale19,078
33,687
Market - off-system sales16,475
17,691
Transmission/Other50,329
49,015
Revenue from contracts with customers288,451
297,577
Other revenues2,768
503
Total revenues$291,219
$298,080
   
Timing of revenue recognition:  
Services transferred over time$288,451
$297,577
Revenue from contracts with customers$288,451
$297,577



The majority of our revenue contracts are based on variable quantities delivered; any fixed consideration contracts with an expected duration of one year or more are immaterial to our revenues. Variable consideration constraints in the form of discounts, rebates, credits, price concessions, incentives, performance bonuses, penalties or other similar items are not material for our revenue contracts. We are the principal in our revenue contracts, as we have control over the services prior to those services being transferred to the customer.

Revenue Not in Scope of ASC 606

Other revenues included in Regulatory liabilities, currentthe table above include revenue accounted for under separate accounting guidance, including alternative revenue programs revenue under ASC 980.

Significant Judgments and Regulatory liabilities, non-currentEstimates
Unbilled Revenue

To the extent that deliveries have occurred but a bill has not been issued, the Company accrues an estimate of the revenue since the latest billing. This estimate is calculated based on several factors including billings through the last billing cycle in a month and prices in effect in our jurisdictions. Each month the estimated unbilled revenue amounts are trued-up and recorded in Accounts receivable, net on the accompanying Balance Sheets.

Contract Balances

The nature of our primary revenue contracts provides an unconditional right to consideration upon service delivery; therefore, no customer contract assets or liabilities exist. The unconditional right to consideration is represented by the balance in our Accounts Receivable and is further discussed above. We do not typically incur costs that would be capitalized, to obtain or fulfill a contract.


(3)    PROPERTY, PLANT AND EQUIPMENT

Property, plant and equipment at December 31 consisted of the following (dollars in thousands):
  2019 2018
  Weighted Weighted
  Average Average
 2019Useful Life (in years)2018Useful Life (in years)
Property, plant, and equipment:    
Production$612,517
46$588,565
46
Transmission235,390
51208,610
48
Distribution431,783
46394,475
45
Plant acquisition adjustment (a)
4,870
324,870
32
General165,342
29154,621
28
Total plant-in-service1,449,902
 1,351,141
 
Construction work in progress44,768
 29,904
 
Total property, plant and equipment1,494,670
 1,381,045
 
Less accumulated depreciation and amortization(400,054) (376,160) 
Total property, plant and equipment, net$1,094,616
 $1,004,885
 
__________________
(a)The plant acquisition adjustment is included in rate base and is being recovered with 11 years remaining.



(4)    JOINTLY OWNED FACILITIES

Our financial statements include our share of several jointly-owned utility facilities as described below. Our share of the facilities’ expenses is reflected in the appropriate categories of operating expenses in the Statements of Income. Each owner of the facility is responsible for financing its investment in the jointly-owned facilities.

We own a 20% interest in the Wyodak Plant (the “Plant”), a coal-fired electric generating station located in Campbell County, Wyoming. PacifiCorp owns the remaining ownership percentage and is the operator of the Plant. We receive our proportionate share of the Plant’s capacity and are committed to pay our share of its additions, replacements and operating and maintenance expenses.

We own a 35% interest in, and are the operator of, the Converter Station Site and South Rapid City Interconnection (the transmission tie), an AC-DC-AC transmission tie. Basin Electric owns the remaining ownership percentage. The transmission tie provides an interconnection between the Western and Eastern transmission grids, which provides us with access to both the WECC region and the SPP region. The total transfer capacity of the transmission tie is 400 MW, including 200 MW West to East and 200 MW from East to West. We are committed to pay our proportionate share of the additions, replacements and operating and maintenance expenses.

We own a 52% interest in the Wygen III power plant. MDU and the City of Gillette each owns an undivided ownership interest in Wygen III and are obligated to make payments for costs associated with administrative services and a proportionate share of the costs of operating the plant for the life of the facility. We retain responsibility for plant operations.

We own 55 MW of the Cheyenne Prairie combined cycle, a 95 MW gas-fired power generation facility located in Cheyenne, Wyoming. Wyoming Electric owns the remaining 40 MW. We are committed to pay our proportionate share of the additions, replacements and operating and maintenance expenses.

As of December 31, 2019, our interests in jointly-owned generating facilities and transmission systems were (in thousands):
Interest in jointly-owned facilitiesPlant in ServiceConstruction Work in ProgressLess Accumulated DepreciationPlant Net of Accumulated Depreciation
Wyodak Plant$116,074
$729
$(64,413)$52,390
Transmission Tie$19,862
$4,161
$(6,612)$17,411
Wygen III$146,161
$400
$(25,518)$121,043
Cheyenne Prairie$92,684
$532
$(14,202)$79,014



(5)    LONG-TERM DEBT

Long-term debt outstanding at December 31 was as follows (in thousands):
  Interest Rate atBalance Outstanding
 Due DateDecember 31, 2019December 31, 2019December 31, 2018
First Mortgage Bonds due 2032August 15, 20327.23%75,000
75,000
First Mortgage Bonds due 2039November 1, 20396.13%180,000
180,000
First Mortgage Bonds due 2044October 20, 20444.43%85,000
85,000
Series 94A Debt (a)
June 1, 20241.84%2,855
2,855
Less unamortized debt discount  (82)(86)
Less unamortized deferred financing costs  (2,597)(2,734)
Long-term Debt, net  340,176340,035
___________________
(a)Variable interest rate at December 31, 2019.

Net deferred financing costs of approximately $2.6 million and $2.7 million were recorded on the accompanying Balance Sheets in long-term debt at December 31, 2019 and 2018, respectively, and are being amortized over the term of the debt. Amortization of deferred financing costs of approximately $0.1 million for each of the years ended December 31, 2019, 2018 and 2017 are included in Interest expense on the accompanying Statements of Income.


Substantially all of our property is subject to the lien of the indenture securing our first mortgage bonds. First mortgage bonds may be issued in amounts limited by property, earnings and other provisions of the mortgage indentures. We were in compliance with our debt covenants at December 31, 2019.

Long-term Debt Maturities

Scheduled maturities of our outstanding long-term debt (excluding unamortized discounts and unamortized deferred financing costs) are as follows (in thousands):
2020$
2021$
2022$
2023$
2024$2,855
Thereafter$340,000



(6)    FAIR VALUE OF FINANCIAL INSTRUMENTS

The estimated fair values of our financial instruments at December 31 were as follows (in thousands):
 20192018
 Carrying ValueFair ValueCarrying ValueFair Value
Cash (a)
$6
$6
$112
$112
Notes payable to Parent (b)
$25,000
$25,000
$
$
Long-term debt (c)
$340,176
$458,286
$340,035
$412,894
_______________
(a)The cash fair value approximates carrying value and therefore is classified as Level 1 in the fair value hierarchy. We believe that the market risk arising from cash in a bank account is minimal.
(b)Carrying value approximates fair value due to the short-term length of maturity; since these borrowings are not traded on an exchange, they are classified in Level 2 in the fair value hierarchy.
(c)Long-term debt is valued based on observable inputs available either directly or indirectly for similar liabilities in active markets and therefore is classified as Level 2 in the fair value hierarchy. Carrying amount of long-term debt is net of deferred financing costs.

Notes payable to Parent

For additional information on our Notes payable to Parent, see Note 14.

Long-Term Debt

For additional information on our long-term debt, see Note 5.


(7)    REGULATORY MATTERS

We had the following regulatory assets and liabilities as follows as of December 31 (in thousands):
Maximum Recovery Period (in years)2016201520192018
Regulatory assets:  
Unamortized loss on reacquired debt (a)
8$1,815
$2,096
Regulatory assets 
Loss on reacquired debt (a)
$989
$1,259
Deferred taxes on AFUDC (b)
459,367
8,571
4,927
5,020
Employee benefit plans (c)
1220,100
20,866
Deferred energy costs (a)
123,016
19,875
Employee benefit plans and related deferred taxes (c)
20,661
19,868
Deferred energy and fuel cost adjustments(a)
23,203
20,334
Deferred taxes on flow through accounting (a)(c)
3512,545
12,104
9,801
8,749
Decommissioning costs (b)
812,456
13,686
6,211
8,196
Other regulatory assets (a) (d)
212,835
8,615
Vegetation management (a)
8,062
10,366
Other regulatory assets (a)
1,843
1,940
Total regulatory assets $92,134
$85,813
75,697
75,732
Less current regulatory assets(21,588)(19,052)
Regulatory assets, non-current$54,109
$56,680
   
Regulatory liabilities:  
Regulatory liabilities 
Cost of removal for utility plant (a)
61$41,541
$38,131
$57,318
$52,366
Employee benefit plans (c)
1212,304
12,616
Employee benefit plans and related deferred taxes (c)
7,023
7,518
Excess deferred income taxes (c)
98,228
100,276
TCJA revenue reserve3,162
2,523
Other regulatory liabilities (c)
13105
836
440
533
Total regulatory liabilities $53,950
$51,583
166,171
163,216
Less current regulatory liabilities(3,162)(2,574)
Regulatory liabilities, non-current$163,009
$160,642
____________________
(a)Recovery    We are allowed a recovery of costs but we are not allowed a rate of return.
(b)In addition to recovery of costs, we are allowed a rate of return.
(c)In addition to recovery or repayment of costs, we are allowed a return on a portion of this amount or a reduction in rate base, respectively.
(d)Includes vegetation management expense of approximately $12.0 million and $5.0 million in 2016 and 2015, respectively.base.


Regulatory assets represent items we expect to recover from customers through probable future increases in rates.


Unamortized Loss on Reacquired Debt - The early redemption premiumLoss on reacquired debt is being amortizedrecovered over the remaining termlife of the original bonds.issue or, if refinanced, over the life of the new issue.


Deferred Taxes on AFUDC - The equity component of AFUDC is considered a permanent difference for tax purposes with the tax benefit being flowed through to customers as prescribed or allowed by regulators. If, based on a regulator’s action, it is probable the utility will recover the future increase in taxes payable represented by this flow-through treatment through a rate revenue increase, a regulatory asset is recognized. This regulatory asset itself is a temporary difference for which a deferred tax liability must be recognized. Accounting standards for income taxes specifically address AFUDC-equity, and require a gross-up of such amounts to reflect the revenue requirement associated with a rate-regulated environment.


Employee Benefit Plans - Employee benefit plans include the unrecognized prior service costs and net actuarial loss associated with our defined benefit pension plansplan and other post-retirement benefit plans in regulatory assets rather than in accumulated other comprehensive income. In addition, this regulatory asset includes the income tax effect of the adjustment required under accounting for compensation-defined benefit plans to record the full pension and post-retirement benefit obligations. Such amounts have been grossed-up to reflect the revenue requirement associated with a rate regulated environment.


Deferred Energy Costsand Fuel Cost Adjustments - Deferred energy and fuel cost adjustments represent the cost of electricity delivered to our utility customers that areis either higher or lower than the current rates and will be recovered or refunded in future rates. Deferred energy and fuel cost adjustments are recorded and recovered or amortized as approved by the appropriate state commission. We file periodic quarterly, semi-annual and/or annual filings to recover these costs based on the respective cost mechanisms approved by the applicable state utility commissions.




Deferred Taxes on Flow-Through Accounting - Under flow-through accounting, the income tax effects of certain tax items are reflected in our cost of service for the customer in the year in which the tax benefits are realized and result in lower utility rates. This regulatory treatment was applied to the tax benefit generated by repair costs that were previously capitalized for tax purposes in a rate case settlement that was reached in 2010. In this instance, the agreed upon rate increase was less than it would have been absent the flow-through treatment. A regulatory asset was established to reflect thethat future increases in income taxes payable will be recovered from customers as the temporary differences reverse. As a result of this regulatory treatment, we continue to record a tax benefit consistent with the flow-through method with respect tofor costs considered repairscurrently deductible for tax purposes, andbut are capitalized for book purposes.


Decommissioning Costs - We received approval in 2014 for regulatory treatment on the remaining net book values and decommissioning costs of our decommissioned coal plants.


Vegetation Management Costs - We received approval in 2013 for regulatory treatment on vegetation management maintenance costs for our distribution system rights-of-way.

Regulatory liabilities represent items we expect to refund to customers through probable future decreases in rates.


Cost of Removal for Utility Plant - Cost of removal for utility plant represents the estimated cumulative net provisions for future removal costs included in depreciation expense for which there is no legal obligation for removal.


Employee Benefit Plans - Employee benefit plans represent the cumulative excess of pension and retiree healthcareother postretirement benefit costs recovered in rates over pension expense recorded in accordance with accounting standards for compensation - retirementcompensation-retirement benefits. In addition, this regulatory liability includes the income tax effect of the adjustment required under accounting for compensation - definedcompensation-defined benefit plans, to record the full pension and post-retirement benefit obligations. Such

Excess Deferred Income Taxes - The revaluation of our deferred tax assets and liabilities due to the passage of the TCJA is recorded as an excess deferred income tax effect has been grossed-up to accountbe refunded to customers primarily using the normalization principles as prescribed in the TCJA. See Note 9 for the revenue requirement aspect ofadditional information.

TCJA Revenue Reserve - Revenue to be returned to customers as a rate regulated environment.

Accounts Receivable and Allowance for Doubtful Accounts

Accounts receivable consists of sales to residential, commercial, industrial, municipal and other customers all of which do not bear interest. These accounts receivable are stated at billed and unbilled amounts net of write-offs or payment received.

We maintain an allowance for doubtful accounts which reflects our best estimate of uncollectible trade receivables. We regularly review our trade receivable allowances by considering such factors as historical experience, credit worthiness, the ageresult of the receivable balances and current economic conditions that may affect collectibility. The allowance is calculated by applying estimated write-off factors to various classes of outstanding receivables, including unbilled revenue. The write-off factors used to estimate uncollectible accounts are based upon consideration of both historical collections experience and management’s best estimate of future collection success givenTCJA. See Note 9 for additional information.

Regulatory Matters

Settlement

On January 7, 2020, South Dakota Electric received approval from the existing collections environment.

Following is a summary of accounts receivable at December 31 (in thousands):
 20162015
Accounts receivable trade$16,972
$15,268
Unbilled revenues13,799
12,795
Allowance for doubtful accounts(157)(207)
Net accounts receivable trade$30,614
$27,856

Revenue Recognition

Revenue is recognized when there is persuasive evidence of an arrangement with a fixed or determinable price, delivery has occurred or services have been rendered, and collectibility is reasonably assured. Sales and franchise taxes collected from our customers is recordedSDPUC on a net basis (excluded from Revenue).

Utility revenues are based on authorized ratessettlement agreement to extend the 6-year moratorium period by an additional 3 years to June 30, 2026. Also, as part of the settlement, we withdrew our application for deferred accounting treatment and expensed $5.4 million of development costs related to projects we no longer intend to construct. This settlement amends a previous agreement approved by the state regulatory agenciesSDPUC on June 16, 2017, whereby South Dakota Electric would not increase base rates, absent an extraordinary event, for a 6 year moratorium period effective July 1, 2017. The moratorium period also includes suspension of both the TFA and EIA.

Renewable Ready

In July 2019, South Dakota Electric and Wyoming Electric received approvals for the FERC. RevenuesRenewable Ready program and related jointly-filed CPCN to construct Corriedale. The wind project will be jointly owned by the sale, transmission2 electric utilities to deliver renewable energy for large commercial, industrial and distribution of energy, and delivery of service are generally recorded when service is rendered or energy is deliveredgovernmental agency customers. In November 2019, South Dakota Electric received approval from the SDPUC to customers. Toincrease the extent that deliveries have occurred but a bill has not been issued, we accrue an estimate of the revenue since the latest billing. This estimate is calculated based upon several factors including billings through the last billing cycle in a month, and prices in effect in our jurisdictions. Each month a true-up of the estimated unbilled revenue amounts are recorded in Receivables- customers, net on the accompanying Balance Sheets.



Materials, Supplies and Fuel

Materials, supplies and fuel used for construction, operation and maintenance purposes are generally stated on a weighted-average cost basis.

Other Current Assets

The following amounts by major classification are included in Other current assets on the accompanying Balance Sheets as of (in thousands):
 December 31, 2016December 31, 2015
Accrued receivables related to litigation expenses and settlements$
$39,050
Other (none of which is individually significant)3,876
4,068
Total other current assets$3,876
$43,118

Deferred Financing Costs

Deferred financing costs are amortized using the effective interest method over the term of the related debt.

Property, Plant and Equipment

Additions to property, plant and equipment are recorded at cost when placed in service. Included in the cost of regulated construction projects is AFUDC, which represents the approximate composite cost of borrowed funds and a return on equity used to finance a regulated utility project. The cost of regulated electric property, plant and equipment retired, or otherwise disposed of in the ordinary course of business, less salvage, is charged to accumulated depreciation. Removal costs associated with non-legal obligations are reclassified from accumulated depreciation and reflected as regulatory liabilities. Ordinary repairs and maintenance of property, except as allowed under rate regulations, are charged to operations as incurred.

Depreciation provisions for regulated electric property, plant and equipment are computed on a straight-line basis using an annual composite rate of 2.2% in 2016, 2.3% in 2015 and 2.3% in 2014.

Accrued Liabilities

The following amounts by major classification are included in Accrued liabilities on the accompanying Balance Sheets as of (in thousands):
 December 31, 2016December 31, 2015
Accrued employee compensation, benefits and withholdings$4,783
$5,054
Accrued property taxes5,522
4,962
Accrued payments related to litigation expenses and settlements
38,750
Accrued income taxes17,069
13,031
Customer deposits and prepayments2,825
2,216
Accrued interest and contract adjustment payments4,614
4,600
Other (none of which is individually significant)2,623
841
Total accrued liabilities$37,436
$69,454



Derivatives and Hedging Activities

From time to time we utilize risk management contracts including forward purchases and sales to hedge the price of fuel for our combustion turbines and fixed-for-float swaps to fix the interest on any variable rate debt. Contracts that qualify as derivatives under accounting standards for derivatives, and that are not exempted such as normal purchase/normal sale, are required to be recorded in the balance sheet as either an asset or liability, measured at its fair value. Accounting standards for derivatives require that changes in the derivative instrument’s fair value be recognized currently in earnings unless specific hedge accounting criteria are met.

Accounting standards for derivatives allow hedge accounting for qualifying fair value and cash flow hedges. Gain or loss on a derivative instrument designated and qualifying as a fair value hedging instrument as well as the offsetting loss or gain on the hedged item attributable to the hedged risk should be recognized currently in earnings in the same accounting period. Conversely, the effective portion of the gain or loss on a derivative instrument designated and qualifying as a cash flow hedging instrument should be reported as a component of other comprehensive income and be reclassified into earnings or as a regulatory asset or regulatory liability, net of tax, in the same period or periods during which the hedged forecasted transaction affects earnings. The remaining gain or loss on the derivative instrument, if any, is recognized currently in earnings.

Revenues and expenses on contracts that qualify are designated as normal purchases and normal sales and are recognized when the underlying physical transaction is completedoffering under the accrual basis of accounting. Normal purchases and normal sales are contracts where physical deliveryprogram by 12.5 MW to 32.5 MW. The 2 electric utilities also received a determination from the WPSC that the wind project can be increased to 52.5 MW. The $79 million project is probable, quantities are expected to be used or soldin service by year-end 2020.


FERC Formula Rate

The annual rate determination process is governed by the FERC formula rate protocols established in the normal course of business over a reasonable amount of time, and price is not tied to an unrelated underlying derivative. As part of our regulated electric operations, we enter into contracts to buy and sell energy to meet the requirements of our customers. These contracts include short-term and long-term commitments to purchase and sell energy in the retail and wholesale markets with the intent and ability to deliver or take delivery. If it was determined that a transaction designated as a normal purchase or normal sale no longer met the exceptions, the fair value of the related contract would be reflected as either an asset or liability, under the accounting standards for derivatives and hedging.

Fair Value Measurements

Accounting standards for fair value measurements provide a single definition of fair value as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date and also requires disclosures and establishes a fair value hierarchy that prioritizes the inputs used to measure fair value. The fair value hierarchy ranks the quality and reliability of the information used to determine fair values giving the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements).

Financial assets and liabilities carried at fair value are classified and disclosed in one of the following three categories:

Level 1 - Unadjusted quoted prices available in active markets that are accessible at the measurement date for identical unrestricted assets or liabilities.

Level 2 - Pricing inputs include quoted prices for identical or similar assets and liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the asset or liability and inputs that are derived principally from or corroborated by observable market data by correlation or other means.

Level 3 - Pricing inputs include significant inputs that are generally less observable from objective sources.

Impairment of Long-Lived Assets

We periodically evaluate whether events and circumstances have occurred which may affect the estimated useful life or the recoverability of the remaining balance of our long-lived assets. If such events or circumstances were to indicate that the carrying amount of these assets was not recoverable, we would estimate the future cash flows expected to result from the use of the assets and their eventual disposition. If the sum of the expected future cash flows (undiscounted and without interest charges) was less than the carrying amount of the long-lived assets, we would recognize an impairment loss.



Income Taxes

We file a federal income tax return with other members of the Parent’s consolidated group. For financial statement purposes, federal income taxes are allocated to the individual companies based on amounts calculated on a separate return basis.

We use the liability method in accounting for income taxes. Under the liability method, deferred income taxes are recognized at currently enacted income tax rates, to reflect the tax effect of temporary differences between the financial and tax basis of assets and liabilities, as well as operating loss and tax credit carryforwards. Such temporary differences are the result of provisions in the income tax law that either require or permit certain items to be reported on the income tax return in a different period than they are reported in the financial statements.

We recognize interest income or interest expense and penalties related to income tax matters in Income tax (expense) benefit on the Statements of Income.

We account for uncertainty in income taxes recognized in the financial statements in accordance with accounting standards for income taxes. The unrecognized tax benefit is classified in Other, non-current liabilities on the accompanying Balance Sheets. See Note 6 for additional information.

Recently Issued and Adopted Accounting Standards

Statement of Cash Flows: Classification of Certain Cash Receipts and Cash Payments, ASU 2016-15

In August 2016, the FASB issued ASU 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments (a consensus of the Emerging Issues Task Force). This ASU requires changes in the presentation of certain items including but not limited to debt prepayment or debt extinguishment costs; contingent consideration payments made after a business combination; proceeds from the settlement of insurance claims; proceeds from the settlement of corporate-owned life insurance policies and distributions received from equity method investees. The ASU will be effective for fiscal years beginning after December 15, 2017. We will use the retrospective transition method to adopt this standard with fiscal years beginning after December 15, 2017.The adoption of this standard will not have a material impact on our financial position, results of operations and cash flows.

Leases, ASU 2016-02

In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842), which supersedes ASC 840, Leases. This ASU requires lessees to recognize a right-of-use asset and lease liability for all leases with terms of more than 12 months. Lessees are permitted to make an accounting policy election to not recognize the asset and liability for leases with a term of 12 months or less. The ASU does not significantly change the lessees’ recognition, measurement and presentation of expenses and cash flows from the previous accounting standard. Lessors’ accounting under the ASC is largely unchanged from the previous accounting standard. In addition, the ASU expands the disclosure requirements of lease arrangements. Lessees and lessors will use a modified retrospective transition approach, which includes a number of practical expedients. The guidance is effective for us beginning after December 15, 2018. Early adoption is permitted. We are currently assessing the impact that adoption of ASU 2016-02 will have on our financial position, results of operations or cash flows.

Disclosures for Investments in Certain Entities That Calculate Net Asset Value per Share (or its Equivalent), ASU 2015-07

On May 1, 2015, the FASB issued ASU 2015-07, Disclosures for Investments in Certain Entities That Calculate Net Asset Value per Share (or its Equivalent). This ASU removes the requirement to categorize within the fair value hierarchy all investments for which fair value is measured using the net asset value per share practical expedient and also removes certain disclosure requirements. The new requirements were effective for us beginningfiled FERC joint-access transmission tariff. Effective January 1, 20162019 the annual revenue requirement increased by $1.9 million and were applied retrospectively to all periods presented,included estimated weighted average capital additions of $31 million for 2018 and 2019 combined. The annual transmission revenue requirement has a true up mechanism that is posted in our 2016 Form 10-K. This ASU did not materially affect our financial statements and disclosures, but did change certain presentation and disclosureJune of the fair value of certain plan assets in our pension and other postretirement benefit plan disclosures in our 2016 Form 10-K, for all periods presented.each year.



Simplifying the Presentation of Debt Issuance Costs, ASU 2015-03

In April 2015, the FASB issued ASU 2015-03, Simplifying the Presentation of Debt Issuance Costs. Debt issuance costs related to a recognized debt liability will be presented on the balance sheet as a direct deduction from the debt liability, similar to the presentation of debt discounts, rather than as an asset. Amortization of these costs will continue to be reported as interest expense. ASU 2015-03 is effective for annual and interim reporting periods beginning after December 15, 2015. We adopted ASU 2015-03 in the first quarter of 2016 on a retrospective basis. As of December 31, 2016, we presented the debt issuance costs, previously reported in other assets, as direct deductions from the carrying amount of long-term debt. The implementation of this standard resulted in reductions of other assets, non-current and long-term debt of approximately $3.1 million in the Balance Sheets as of December 31, 2015.

Revenue from Contracts with Customers, ASU 2014-09
In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers. The standard provides companies with a single model for use in accounting for revenue arising from contracts with customers and supersedes current revenue recognition guidance, including industry-specific revenue guidance. The core principle of the model is to recognize revenue when control of the goods or services transfers to the customer. The new disclosure requirements will provide information about the nature, amount, timing and uncertainty of revenue and cash flows from revenue contracts with customers. The guidance is effective for annual and interim reporting periods beginning after December 15, 2017 with early adoption on January 1, 2017 permitted. Entities will have the option of using either a full retrospective or modified retrospective approach to adopting this guidance. Under the modified approach, an entity would recognize the cumulative effect of initially applying the guidance with an adjustment to the opening balance of retained earnings in the period of adoption.

We will adopt this standard for annual and interim reporting periods beginning after December 15, 2017 and are actively assessing all of our sources of revenue to determine the impact that adoption of the new standard will have on our financial position, results of operations and cash flows. Our evaluation includes identifying revenue streams by like contracts to allow for ease of implementation. A majority of our revenues are from regulated tariff offerings that provide electricity with a defined contractual term. For such arrangements, we expect that the revenue from contracts with the customer will be equivalent to the electricity delivered in that period. Therefore, we do not expect that there will be a significant shift in the timing or pattern of revenue recognition for regulated tariff-based sales. The evaluation of other revenue streams is ongoing, including those tied to longer term contractual commitments. However, a number of industry-specific implementation issues are still unresolved and the final resolution of these issues could impact our current accounting policies and/or patterns for revenue recognition, as well as the transition method selected.



(2)    PROPERTY, PLANT AND EQUIPMENT

Property, plant and equipment at December 31 consisted of the following (dollars in thousands):
  2016 2015 
  Weighted Weighted  
  Average AverageLives (in years)
 2016Useful Life (in years)2015Useful Life (in years)MinimumMaximum
Electric plant:      
Production$576,833
46$569,182
463063
Transmission147,398
48117,708
484070
Distribution364,304
46353,241
461575
Plant acquisition adjustment (a)
4,870
324,870
323232
General88,114
2388,939
22365
Total plant-in-service1,181,519
 1,133,940
   
Construction work in progress54,868
 32,186
   
Total electric plant1,236,387
 1,166,126
   
Less accumulated depreciation and amortization(338,828) (326,074)   
Electric plant net of accumulated depreciation and amortization$897,559
 $840,052
   
__________________
(a)The plant acquisition adjustment is included in rate base and is being recovered with 14 years remaining.


(3)    JOINTLY OWNED FACILITIES

(8)    LEASES

We use the proportionate consolidation method to accounthave a ground lease for our percentage interest in the assets, liabilities and expenses of the following facilities:

We own a 20% interest in the Wyodak Plant (the “Plant”), a coal-fired electric generating station located in Campbell County, Wyoming. PacifiCorp owns the remaining ownership percentage and is the operator of the Plant. We receive our proportionate share of the Plant’s capacity and are committed to pay our share of its additions, replacements and operating and maintenance expenses.

We own a 35% interest in, and are the operator of, the Converter Station Site and South Rapid City Interconnection (the transmission tie), an AC-DC-AC transmission tie. Basin Electric owns the remaining ownership percentage. The transmission tie provides an interconnection between the Western and Eastern transmission grids, which provides us with access to both the WECC region and the MAPP region. The total transfer capacity of the transmission tie is 400 MW, including 200 MW West to East and 200 MW from East to West. We are committed to pay our proportionate share of the additions, replacements and operating and maintenance expenses.

We own a 52% interest in the Wygen III power plant. MDUgenerating facility with an affiliate and the City of Gillette each owns an undivided ownership interest in Wygen IIIcommunication tower site and are obligatedoperation center facility leases with third parties. Our leases have remaining terms ranging from 1 year to make payments for costs associated with administrative services and a proportionate share of the costs of operating the plant for the life of the facility. We retain responsibility for plant operations.

We own 55 MW of Cheyenne Prairie, a 95 MW gas-fired power generation facility located in Cheyenne, Wyoming. Wyoming Electric owns the remaining 40 MW. This facility was placed into commercial operations on October 1, 2014. We are committed to pay our proportionate share of the additions, replacements and operating and maintenance expenses.

30 years.
The investments in our jointly owned plants and accumulated depreciation are included in the corresponding captions in the accompanying Balance Sheets. Our sharecomponents of direct expenses of the Plants is included in the corresponding categories of operating expenses in the accompanying Statements of Income. Each of the respective owners is responsible for providing its own financing.



As of December 31, 2016, our interests in jointly-owned generating facilities and transmission systems included on our Balance Sheetslease expense were as follows (in thousands):
 Income Statement LocationFor the year ended December 31, 2019
Operating lease costOperations and maintenance$908
Variable lease costOperations and maintenance137
Total lease cost $1,045

Interest in jointly-owned facilitiesPlant in ServiceConstruction Work in ProgressAccumulated Depreciation
Wyodak Plant$113,611
$256
$55,878
Transmission Tie$19,978
$13
$5,793
Wygen III$138,261
$1,806
$17,635
Cheyenne Prairie$91,365
$155
$6,015


(4)    LONG-TERM DEBT

Long-term debt outstanding at December 31Supplemental balance sheet information related to leases was as follows (in thousands):
 Balance Sheet LocationAs of December 31, 2019
Assets:  
Operating lease assetsOther assets, non-current$14,374
Total lease assets $14,374
   
Liabilities:  
Current:  
Operating leasesAccrued liabilities$293
   
Noncurrent:  
Operating leasesOther deferred credits and other liabilities14,105
Total lease liabilities $14,398

 Maturity DateInterest Rate20162015
First Mortgage Bonds due 2032August 15, 20327.23%$75,000
$75,000
First Mortgage Bonds due 2039November 1, 20396.125%180,000
180,000
First Mortgage Bonds due 2044October 20, 20444.43%85,000
85,000
Unamortized Discount, First Mortgage Bonds due 2039  (94)(99)
Series 94A Debt (a)
June 1, 20240.88%2,855
2,855
Unamortized Debt Expense  (3,005)(3,140)
Long-term Debt  $339,756
$339,616

___________________Supplemental cash flow information related to leases was as follows (in thousands):
 For the year ended December 31, 2019
Cash paid for amounts included in the measurement of lease liabilities: 
Operating cash flows from operating leases$912
Right-of-use assets obtained in exchange for lease obligations: 
Operating leases$


(a)Variable interest rate atAs of December 31, 2016.2019
Weighted average remaining lease term (years):
Operating leases30 years
Weighted average discount rate:
Operating leases4.3%

Net deferred financing costs of approximately $3.0 million and $3.1 million were recorded on the accompanying Balance Sheets in long-term debt at December 31, 2016 and 2015, respectively, and are being amortized over the term of the debt. Amortization of deferred financing costs of approximately $0.1 million, $0.1 million and $0.1 million for the years ended December 31, 2016, 2015 and 2014, respectively, are included in Interest expense on the accompanying Statements of Income.

Substantially all of our property is subject to the lien of the indenture securing our first mortgage bonds. First mortgage bonds may be issued in amounts limited by property, earnings and other provisions of the mortgage indentures. We were in compliance with our debt covenants at December 31, 2016.

Long-term Debt Maturities

Scheduled maturities of our outstanding long-term debt (excluding unamortized discounts) are as follows (in thousands):
2017$
2018$
2019$
2020$
2021$
Thereafter$342,855




(5)    FAIR VALUE OF FINANCIAL INSTRUMENTS

The estimated fair values of our financial instruments at December 31operating lease liabilities for future years were as follows (in thousands):
 20162015
 Carrying ValueFair ValueCarrying ValueFair Value
Cash and cash equivalents (a)
$234
$234
$297
$297
Long-term debt (b)
$339,756
$410,466
$339,616
$404,864
 Total
2020$912
2021911
2022911
2023908
2024906
Thereafter21,128
Total lease payments25,676
Less imputed interest11,278
Present value of lease liabilities$14,398
_______________
(a)Fair value approximates carrying value due to either short-term length of maturity or variable interest rates that approximate prevailing market rates and therefore is classified in Level 1 in the fair value hierarchy.
(b)Long-term debt is valued using the market approach based on observable inputs of quoted market prices and yields available for debt instruments either directly or indirectly for similar maturities and debt ratings in active markets and therefore is classified in Level 2 in the fair value hierarchy. The carrying amount of our variable rate debt approximates fair value due to the variable interest rates with short reset periods. For additional information on our long-term debt see Note 4.


As previously disclosed in Note 11 of the Notes to the Financial Statements in our 2018 Annual Report on Form 10-K, prior to the adoption of ASU 2016-02, Leases (Topic 842), the future minimum payments required under operating lease agreements as of December 31, 2018 were as follows (in thousands):
 Operating Leases
2019$911
2020856
2021855
2022856
2023853
Thereafter21,947
Total lease payments 
$26,278



(9)    INCOME TAXES

On December 22, 2017, the U.S. government enacted comprehensive tax legislation commonly referred to as the TCJA. The following methodsTCJA reduced the U.S. federal corporate tax rate from 35% to 21%. As such, the Company has remeasured the deferred income taxes at the 21% federal tax rate as of December 31, 2017. As a result of the revaluation at December 31, 2017, deferred tax assets and assumptionsliabilities were usedreduced by approximately $103 million. Of the $103 million, approximately $101 million was ultimately reclassified to estimatea regulatory liability. As of December 31, 2019 we have a regulatory liability associated with TCJA related items of $98 million. A significant portion of the fair value of each class of our financial instruments.

Cash and Cash Equivalents

Included in cash and cash equivalents is cash and overnight repurchase agreement accounts. As part of our cash management process, excess operating cash is invested in overnight repurchase agreements with our bank. Repurchase agreementsdeferred taxes are not deposits and are not insuredsubject to the average rate assumption method, as prescribed by the U.S. Government,IRS, and will generally be amortized as a reduction of customer rates over the FDIC or any other government agency and involve investment risk including possible lossremaining lives of principal. We believe however, that the market risk arising from holding these financial instruments is minimal.related assets. As of December 31, 2019, the Company has amortized $3.1 million of this regulatory liability.



(6)    INCOME TAXES

Income tax expense (benefit) from continuing operations for the years ended December 31 was as follows (in thousands):

 201920182017
Current:   
Federal$13,782
$5,454
$13,124
    
Deferred:   
Federal(4,281)5,218
1,004
    
Total income tax expense$9,501
$10,672
$14,128

 201620152014
Current$1,838
$14,910
$(6)
Deferred20,690
7,690
16,518
Total income tax expense$22,528
$22,600
$16,512


The temporary differences, which gave rise to the net deferred tax liability, for the years ended December 31 were as follows (in thousands):
 20192018
Deferred tax assets:  
Regulatory liabilities$25,623
$25,587
Other9,128
4,721
Total deferred tax assets34,751
30,308
   
Deferred tax liabilities:  
Accelerated depreciation and other plant related differences(125,138)(125,594)
Regulatory assets(7,193)(7,147)
Deferred costs(8,264)(8,572)
Other(6,358)(3,004)
Total deferred tax liabilities(146,953)(144,317)
   
Net deferred tax liability$(112,202)$(114,009)

 20162015
Deferred tax assets:  
Employee benefits$5,163
$4,683
Regulatory liabilities9,099
9,908
Other1,815
16,186
Total deferred tax assets16,077
30,777
   
Deferred tax liabilities:  
Accelerated depreciation and other plant related differences (a)
(202,047)(196,237)
Regulatory assets(4,391)(4,236)
Employee benefits(3,075)(3,003)
Deferred costs(16,920)(14,765)
Other(1,087)(1,497)
Total deferred tax liabilities(227,520)(219,738)
   
Net deferred tax assets (liabilities)$(211,443)$(188,961)
_________________________
(a)To conform to the 2016 presentation of accelerated depreciation and other plant-related differences, 2015 is net of deferred tax liabilities of $8.6 million, previously presented as AFUDC Equity.


The effective tax rate differs from the federal statutory rate for the years ended December 31, as follows:
201620152014201920182017
Federal statutory rate35.0 %35.0 %35.0 %21.0%35.0%
Amortization of excess deferred and investment tax credits(0.4)(0.1)(0.3)(3.0)(1.3)(0.1)
AFUDC Equity(0.9)(0.6)(0.1)
Flow through adjustments (a)
(0.9)(0.9)(1.9)
Tax credits(0.1)
(0.2)
Flow-through adjustments (a)
(1.5)(1.7)(1.8)
TCJA corporate rate reduction (b)
2.5(9.2)
Other0.6

0.5
0.3(1.6)(2.3)
33.3 %33.4 %33.0 %16.8%18.9%21.6%
_________________________
(a)The flow-throughFlow-through adjustments related primarily to an accounting method change for tax purposes that allows us to take a current tax deduction for repair costs that continue to be capitalized for book purposes.costs. We recorded a deferred income tax liability in recognition of the temporary difference created between book and tax treatment and we flowed the tax benefit through to tax expense.
(b)On December 22, 2017, the TCJA was signed into law reducing the federal corporate rate from 35% to 21%, effective January 1, 2018. The 2017 effective tax rate reduction reflects the revaluation of deferred income taxes required by the change. During the year ended December 31, 2018, we recorded approximately $0.9 million of additional tax expense associated with changes in the prior estimated impacts of TCJA related items.




The following table reconciles the total amounts of unrecognized tax benefits, without interest, included in Other deferred credits and other liabilities on the accompanying Balance Sheet (in thousands):
 20192018
Unrecognized tax benefits at January 1$249
$302
Additions for current year tax positions

Additions for prior year tax positions
2
Reductions for prior year tax positions(33)(55)
Unrecognized tax benefits at December 31$216
$249

 20162015
Unrecognized tax benefits at January 1$2,264
$1,623
Additions for prior year tax positions1,194
888
Reductions for prior year tax positions(682)(247)
Settlements for prior year tax positions(2,283)
Unrecognized tax benefits at December 31$493
$2,264


The total amount of unrecognized tax benefits that, if recognized, would impact the effective tax rate is approximately $0.2 million. The reductions for prior year tax positions relate primarilynot material to the IRS settlement as discussed below.

We file income tax returns in the United States federal jurisdictions as a memberfinancial results of the BHC consolidated group.Company.


It is ourthe Company’s continuing practice to recognize interest and/or penalties related to income tax matters in income tax expense. During the years ended December 31, 20162019 and 2015,2018, the interest expense recognized was not material to ourthe financial results.results of the Company.

In January 2016, we reached a settlement in principle with IRS Appeals with respect to research and development tax credits and deductions for tax years 2007 through 2009. The settlement resulted in a reduction of approximately $2.9 million excluding interest. Accumulated deferred income taxes were restored by approximately $0.6 million and approximately $2.3 million was reclassified to current taxes payable.

We do not anticipate that total unrecognized tax benefits will significantly change due to the settlement of any audits or the expiration of statutes of limitations on or before December 31, 2017.2020.


At December 31, 2016, we are no longerWe file income tax returns in the United States federal jurisdictions as a federal NOL carry forward position.member of the BHC consolidated group.



(710)    OTHER COMPREHENSIVE INCOME


We record deferred gains (losses) in AOCI related to interest rate swaps designated as cash flow hedges and the amortization of components of our defined benefit plans. Deferred gains (losses) related to our interest rate swaps are recognized in earnings as they are amortized.

The componentsfollowing table details reclassifications out of AOCI and into net income. The amounts in parentheses below indicate decreases to net income in the reclassification adjustmentsStatements of Income for the period, net of tax included in Other Comprehensive Income were as follows (in thousands):
 Location on the Statements of IncomeAmounts Reclassified from AOCI
  December 31, 2019December 31, 2018
Gains and (losses) on cash flow hedges:   
Interest rate swapsInterest expense$(64)$(64)
Income taxIncome tax benefit (expense)132
13
Total reclassification adjustments related to cash flow hedges, net of tax $68
$(51)
    
Amortization of components of defined benefit plans:   
Actuarial gain (loss)Operations and maintenance$(65)$(103)
Income taxIncome tax benefit (expense)166
22
Total reclassification adjustments related to defined benefit plans, net of tax $101
$(81)

 Location on the Statements of IncomeAmounts Reclassified from AOCI
  20162015
Gains and Losses on cash flow hedges:   
Interest rate swaps gain (loss)Interest expense$64
$64
Income taxIncome tax benefit (expense)(22)319
Total reclassification adjustments related to cash flow hedges, net of tax $42
$383
    
Amortization of defined benefit plans:   
Actuarial gain (loss)Operations and maintenance$82
$94
Income taxIncome tax benefit (expense)(29)(33)
Total reclassification adjustments related to defined benefit plans, net of tax $53
$61


Derivatives designated as cash flow hedges relate to a treasury lock entered into in August 2002 to hedge $50 million of our First Mortgage Bonds due on August 15, 2032.2032. The treasury lock cash settled on August 8, 2002,, the bond pricing date, and resulted in a $1.8 million loss. The treasury lock is treated as a cash flow hedge and the resulting loss is carried in Accumulated other comprehensive loss and is being amortized over the life of the related bonds.




Balances by classification included within Accumulated other comprehensive lossAOCI, net of tax, on the accompanying Balance Sheets were as follows (in thousands):
 Derivatives Designated as Cash Flow Hedges  
 Interest Rate SwapsEmployee Benefit PlansTotal
    
As of December 31, 2018$(500)$(391)$(891)
Other comprehensive income (loss) before reclassifications
(320)(320)
Amounts reclassified from AOCI(68)(101)(169)
As of December 31, 2019$(568)$(812)$(1,380)
    
  
 Derivatives Designated as Cash Flow Hedges  
 Interest Rate SwapsEmployee Benefit PlansTotal
    
As of December 31, 2017$(551)$(707)$(1,258)
Other comprehensive income (loss) before reclassifications
235
235
Amounts reclassified from AOCI51
81
132
As of December 31, 2018$(500)$(391)$(891)

 Interest Rate SwapsEmployee Benefit PlansTotal
    
As of December 31, 2015$(635)$(672)$(1,307)
Other comprehensive income (loss)42
3
45
As of December 31, 2016$(593)$(669)$(1,262)
    
  
 Interest Rate SwapsEmployee Benefit PlansTotal
    
As of December 31, 2014$(1,018)$(801)$(1,819)
Other comprehensive income (loss)383
129
512
As of December 31, 2015$(635)$(672)$(1,307)



(811)    SUPPLEMENTAL CASH FLOW INFORMATION

Years ended December 31,201920182017
 (in thousands)
Non-cash investing and financing activities -   
Accrued property, plant and equipment purchases at December 31$12,305
$15,180
$6,565
Non-cash decrease to money pool note receivable, net$
$(36,000)$(42,000)
Non-cash dividend to Parent$
$36,000
$42,000
    
Cash (paid) refunded during the period for -   
Interest (net of amounts capitalized)$(21,909)$(21,988)$(21,517)
Income taxes (paid), net$(24,372)$(10,394)$(12,719)



(12)    EMPLOYEE BENEFIT PLANS


Funded Status of BenefitDefined Contribution Plans


We apply accounting standardsBHC sponsors a 401(k) retirement savings plan (the 401(k) Plan). Participants in the 401(k) Plan may elect to invest a portion of their eligible compensation to the 401(k) Plan up to the maximum amounts established by the IRS. The 401(k) Plan provides employees the opportunity to invest up to 50% of their eligible compensation on a pre-tax or after-tax basis.

The 401(k) Plan provides a Company matching contribution for regulated operations,all eligible participants. Certain eligible participants who are not currently accruing a benefit in the Pension Plan also receive a Company retirement contribution based on the participant’s age and accordingly,years of service. Vesting of all Company and matching contributions occurs at 20% per year with 100% vesting when the unrecognized net periodic benefit cost that would have been reclassified to Accumulated other comprehensive income (loss) was alternatively recorded as a regulatory asset or regulatory liability, netparticipant has 5 years of tax.service with the Company.


Defined Benefit Pension Plan


We have aone defined benefit pension plan, (“the Black Hills Retirement Plan (Pension Plan). The Pension Plan”) coveringPlan covers certain eligible employees.employees of the Company. The benefits for the Pension Plan are based on years of service and calculations of average earnings during a specific time period prior to retirement. The Pension Plan has beenis closed to new employees and frozen for certain employees who did not meet age and service based criteria.


Black Hills RetirementThe Pension Plan assets are held in a Master Trust. Due to the plan merger on December 31, 2016, reporting beginning in 2017 will no longer represent an undivided interest in the Master Trust. Our Board of Directors has approved the Plans’Pension Plan’s investment policy. The objective of the investment policy is to manage assets in such a way that will allow the eventual settlement of our obligations to the Pension Plans’Plan’s beneficiaries. To meet this objective, our pension assets are managed by an outside adviser using a portfolio strategy that will provide liquidity to meet the Plans’Pension Plan’s benefit payment obligations. The Pension Plans’Plan’s assets consist primarily of equity, fixed income and hedged investments.


The expected rate of return on pension planthe Pension Plan assets is determined by reviewing the historical and expected returns of both equity and fixed income markets, taking into account asset allocation, the correlation between asset class returns, and the mix of active and passive investments. The Pension Plan utilizes a dynamic asset allocation where the target allocation range to return-seeking and liability-hedging assets is determined based on a targeted asset allocation range determined by the funded ratiostatus of the plan.Plan. As of December 31, 2016,2019, the expected rate of return on pension plan assets is based on the targeted asset allocation range of 44%29% to 52% equity and other37% return-seeking assets and 48%63% to 56% fixed-income71% liability-hedging assets, and the expected rate of return from the associated asset categories.assets.


The expected long-term rate of return for investments was 6.75% for the 2016 and 2015 plan years. Our Pension Plan funding policy is funded in accordancecompliance with the federal government’s funding requirements.


Pension Plan Assets


The percentages of total plan asset fair value by investment category of our Pension Plan assets at December 31 were as follows:
 20192018
Equity securities20%17%
Real estate3
4
Fixed income funds71
71
Cash and cash equivalents2
3
Hedge funds4
5
Total100%100%

 20162015
Equity securities28%26%
Real estate5
5
Fixed income funds57
59
Cash and cash equivalents2
1
Hedge funds8
9
Total100%100%


Supplemental Non-qualified Defined Benefit Retirement Plans


We have various supplemental retirement plans (“Supplemental Plans”) for key executives.executives of the Company. The Supplemental Plansplans are non-qualified defined benefit plans.and defined contribution plans (Supplemental Plans). The Supplemental Plans are subject to various vesting schedules.

Supplemental Plan Assets

We fund our Supplemental Plansschedules and are funded on a cash basis as benefits are paid.


Non-pension Defined Benefit Postretirement Healthcare Plan


EmployeesBHC sponsors a retiree healthcare plan (Healthcare Plan) for employees who are participants in our Postretirementmeet certain age and service requirements at retirement. Healthcare Plan (“Healthcare Plan”) and who retire on or after attaining minimum age and years of service requirements are entitled to postretirement healthcare benefits. These benefits are subject to premiums, deductibles, co-payment provisions and other limitations. We may amend or changePre-65 retirees receive their retiree medical benefits through the Healthcare Plan periodically. We are not pre-funding ourBlack Hills self-insured retiree medical plan. We have determined that the Healthcare Plan’s post-65 retiree prescription drug plans are actuarially equivalent and qualifycoverage for the Medicare Part D subsidy.Medicare-eligible BHP retirees is provided through an individual market healthcare exchange.




Plan Assets


We fund our Healthcare PlansPlan on a cash basis as benefits are paid.


Plan Contributions and Estimated Cash Flows


CashContributions to the Pension Plan are cash contributions for pension plans are made directly to the Master Trust accounts.Trust. Healthcare benefits include company and Supplemental Plan contributions are made in the form of benefit payments. participant paid premiums.

Contributions for the years ended December 31 were as follows (in thousands):
 20192018
Defined Contribution Plan  
Company retirement contributions$888
$876
Company matching contributions$1,275
$1,272

 20162015
Defined Benefit Plans  
Defined Benefit Pension Plan$820
$
Defined Benefit Postretirement Healthcare Plan$279
$267
Supplemental Non-qualified Defined Benefit Plan$221
$211
   
Defined Contribution Plans  
Company Retirement Contribution$851
$811
Matching Contributions$1,400
$1,423


 20192018
Defined Benefit Plans  
Defined Benefit Pension Plan$1,753
$1,795
Non-Pension Defined Benefit Postretirement Healthcare Plan$739
$388
Supplemental Non-qualified Defined Benefit Plans$266
$238


While we do not have required contributions, we expect to make approximately $1.3$1.7 million in contributions to our Defined Benefit Pension Plan in 2017.2020.


Fair Value Measurements


Assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. OurThe Company’s assessment of the significance of a particular input to the fair value measurement requires judgment and may affect their placement within the fair value hierarchy levels.

The following tables set forth, by level within the fair value hierarchy, the assets that were accounted for at fair value on a recurring basis as of December 31 (in thousands):
Defined Benefit Pension Plan2016
Pension PlanDecember 31, 2019
Level 1Level 2Level 3
NAV (a)
Total Fair ValueLevel 1Level 2Level 3Total Investments Measured at Fair Value
NAV (a)
Total Investments
AXA Equitable General Fixed Income$
$8
$
$8
$
$8
Common Collective Trust - Cash and Cash Equivalents$
$980
$

$980

978

978

978
Common Collective Trust - Equity
14,927


14,927

12,072

12,072

12,072
Common Collective Trust - Fixed Income
31,003


31,003

42,449

42,449

42,449
Common Collective Trust - Real Estate
347

2,300
2,647




1,974
1,974
Hedge Funds


4,331
4,331




2,709
2,709
Total investments measured at fair value$
$47,257
$
6,631
$53,888
$
$55,507
$
$55,507
$4,683
$60,190




Pension PlanDecember 31, 2018
 Level 1Level 2Level 3Total Investments Measured at Fair Value
NAV (a)
Total Investments
AXA Equitable General Fixed Income$
$261
$
$261
$
$261
Common Collective Trust - Cash and Cash Equivalents
1,388

1,388

1,388
Common Collective Trust - Equity
9,436

9,436

9,436
Common Collective Trust - Fixed Income
39,047

39,047

39,047
Common Collective Trust - Real Estate
9

9
1,896
1,905
Hedge Funds



2,627
2,627
Total investments measured at fair value$
$50,141
$
$50,141
$4,523
$54,664
Defined Benefit Pension Plan2015
 Level 1Level 2Level 3
NAV (a)
Total Fair Value
Common Collective Trust - Cash and Cash Equivalents$
$498
$

$498
Common Collective Trust - Equity
14,198


$14,198
Common Collective Trust - Fixed Income
32,615


$32,615
Common Collective Trust - Real Estate
418

2,113
$2,531
Hedge Funds


4,881
4,881
Total investments measured at fair value$
$47,729
$
6,994
$54,723

________________________
(a)Certain investments that are measured at fair value using Net Asset Value “NAV”NAV per share (or its equivalent) for practical expedient have not been classified in the fair value hierarchy. The fair value amounts presented in these tables for these investments are intended to permit reconciliation of the fair value hierarchy to the amounts presented in the reconciliation of changes in the plans’plan’s benefit obligations and fair value of plan assets below.above.


Common Collective Trust - Cash and Cash Equivalents: This category is comprised of theAXA Equitable General Fixed Income Fundand Common Collective Trusts - cash and cash equivalents. The AXA Equitable General Fixed Income Fund: This fund is a fund of diversified portfolios,portfolio, primarily composed of fixed income instruments. Assets are invested in long-term holdings, such as commercial, agricultural and residential mortgages, publicly traded and privately placed bonds and real estate as well as short-term bonds. Fair values of mortgage loans are measured by discounting future contractual cash flows to be received on the mortgage loans using interest rates whichof loans with similar characteristics have.characteristics. The discount rate is derived from taking the appropriate U.S. Treasury rate with a like term. The fair valuesvalue of public fixed maturity securities are generally based on prices obtained from independent valuation service providers with reasonableness prices compared with directly observable market trades. The fair valuesvalue of privately placed securities are determined using a discounted cash flow model. These models use observable inputs with a discount rate based upon the average of spread surveys collected from private market intermediaries and industry sector of the issuer. The Plan’s investments in the AXA Equitable General Fixed Income Fund are categorized as Level 2.

Common Collective Trust - Trust Funds: The Plan holds units of various Common Collective Trust Funds offered through a private placement. The unitsThese funds are valued daily usingbased upon the NAV. The NAVs areredemption price of units held by the Plan, which is based on the current fair value of eachthe common collective trust funds’ underlying assets. Unit values are determined by the financial institution sponsoring such funds by dividing the fund’s underlying investments. Level 1net assets are priced using quotes for trades occurring in active markets forat fair value by its units outstanding at the identical asset. Level 2 assets are priced using observable inputs for the asset (for example, interest rates and yield curves observable at commonly quoted intervals, volatilities, prepayment speeds, loss severities, credit risks, and default rates) or inputs that are derived principally from or corroborated by observable market data by correlation or other means (market-corroborated inputs).valuation dates. The Plan’s investments in common collective trust funds, with the exception of shares of the common collective trust realtrust-real estate are categorized as Level 2.


Common Collective Trust - RealTrust-Real Estate Fund: This fund is valued based on various factors of the underlying real estate properties, including market rent, market rent growth, occupancy levels, etc. As part of the trustee’s valuation process, properties are externally appraised generally on an annual basis. The appraisals are conducted by reputable independent appraisal firms and signed by appraisers that are members of the Appraisal Institute, with professional designation of Member, Appraisal Institute. All external appraisals are performed in accordance with the Uniform Standards of Professional Appraisal Practices. We receive monthly statements from the trustee, along with the annual schedule of investments and rely on these reports for pricing the units of the fund. Some of the funds without participant withdrawal limitations are categorized as Level 2.

The following investments are measured at NAV and are not classified in the fair value hierarchy, in accordance with accounting guidance:
Common Collective Trust-Real Estate Fund: This is the same fund as above except that certain of the funds’ assets contain participant withdrawal policies with restrictions on redemption and are therefore not included in the fair value hierarchy.
Hedge Funds: HedgeThese funds represent investments in other investment funds that seek a return utilizing a number of diverse investment strategies. The strategies, when combined, aim to reduce volatility and risk while attempting to deliver positive returns under all market conditions. Amounts are reported on a one-month lag. The fair value of hedge funds is determined using net asset value per share based on the fair value of the hedge fund’s underlying investments. Generally,20% of the shares may be redeemed at the end of each month with a 10-day notice and full redemptions are available at the end of each quarter with a 65 day30-day notice and areis limited to a percentage of the total net assetassets value of the fund. The net asset values are based on the fair value of each fund’s underlying investments. There are no unfunded commitments related to these hedge funds.

Other Plan ReconciliationsInformation


The following tables provide a reconciliation of the Employee Benefit Plan’semployee benefit plan obligations, and fair value of assets and amounts recognized in the Balance Sheets, components of the net periodic expense and elements of regulatory assets and liabilities and AOCI (in thousands):AOCI:


Benefit Obligations
 Defined Benefit Pension PlanSupplemental Non-qualified Defined Benefit PlansNon-pension Defined Benefit Postretirement Healthcare Plan
As of December 31 (in thousands)201920182019201820192018
Change in benefit obligation:      
Projected benefit obligation at beginning of year$61,919
$67,562
$2,992
$3,418
$5,055
$5,970
Service cost365
516


148
193
Interest cost2,410
2,194
114
108
186
179
Actuarial loss (gain)7,482
(2,878)406
(296)507
(889)
Benefits paid(5,234)(3,562)(266)(238)(739)(389)
Plan participants transfer to affiliate119
(1,913)

(77)(129)
Plan participants’ contributions



96
120
Projected benefit obligation at end of year$67,061
$61,919
$3,246
$2,992
$5,176
$5,055

 Defined Benefit Pension PlanSupplemental Non-qualified Defined Benefit Retirement PlansDefined Benefit Postretirement Healthcare Plan
 201620152016201520162015
Change in benefit obligation:      
Projected benefit obligation at beginning of year$65,959
$71,178
$3,426
$3,599
$6,208
$6,038
Service cost606
797


204
233
Interest cost2,499
2,956
122
142
187
214
Actuarial loss (gain)455
(5,650)78
(104)(446)27
Benefits paid(3,215)(3,284)(222)(211)(420)(387)
Plan participants transfer to affiliate (a)
(1,331)(38)

(31)(7)
Medicare Part D adjustment




(30)
Plan participants’ contributions



141
120
Projected benefit obligation at end of year$64,973
$65,959
$3,404
$3,426
$5,843
$6,208


A reconciliation of the fair value ofEmployee Benefit Plan assets (as of the December 31 measurement date) is as follows (in thousands):Assets
 Defined Benefit Pension PlanSupplemental Non-qualified Defined Benefit PlansNon-pension Defined Benefit Postretirement Healthcare Plan
As of December 31 (in thousands)201920182019201820192018
Beginning fair value of plan assets$54,664
$59,884
$
$
$
$
Investment income (loss)8,902
(1,884)



Employer contributions1,753
1,795
266
238
643
268
Retiree contributions



96
120
Benefits paid(5,234)(3,563)(266)(238)(739)(388)
Plan participants transfer to affiliate105
(1,568)



Ending fair value of plan assets$60,190
$54,664
$
$
$
$

 Defined Benefit Pension PlanSupplemental Non-qualified Defined Benefit Retirement PlansDefined Benefit Postretirement Healthcare Plan
 201620152016201520162015
Beginning fair value of plan assets$54,723
$59,098
$
$
$
$
Investment income (loss)2,485
(1,057)



Benefits paid(3,215)(3,284)(221)(211)(420)(387)
Participant contributions



279
120
Employer contributions820

221
211
141
267
Plan participants transfer to affiliate(a)
(925)(34)



Ending fair value of plan assets$53,888
$54,723
$
$
$
$
__________________
(a)Change is related to the merger of the three defined benefit pension plans maintained by Black Hills Corporation into one plan as of December 31, 2016.



The funded status of the plans and amounts recognized in the Balance Sheets at December 31 consist of (in thousands):
 Defined Benefit Pension PlanSupplemental Non-qualified Defined Benefit PlansNon-pension Defined Benefit Postretirement Healthcare Plan
 201920182019201820192018
Regulatory asset$20,117
$19,099
$
$
$
$
Current liability$
$
$321
$230
$586
$466
Non-current liability$7,121
$7,255
$2,925
$2,762
$4,590
$4,589
Regulatory liability$
$
$
$
$1,675
$2,441

 Defined Benefit Pension PlanSupplemental Non-qualified Defined Benefit Retirement PlansNon-pension Defined Benefit Postretirement Plan
 201620152016201520162015
Regulatory asset (liability)$18,974
$19,816
$
$
$(2,087)$(1,946)
Current liability$
$
$(247)$(216)$(541)$(619)
Non-current liability$(11,085)$(11,236)$(3,157)$(3,210)$(5,302)$(5,587)



Accumulated Benefit Obligation (in thousands)
 Defined Benefit Pension PlanSupplemental
Non-qualified Defined Benefit Plans
Non-pension Defined Benefit Postretirement Healthcare Plan
As of December 31 (in thousands)201920182019201820192018
Accumulated benefit obligation$65,225
$59,987
$3,246
$2,992
$5,176
$5,055

 Defined Benefit Pension PlanSupplemental Non-qualified Defined Benefit Retirement PlansNon-pension Defined Benefit Postretirement Healthcare Plan
 201620152016201520162015
Accumulated benefit obligation$61,585
$62,240
$3,404
$3,426
$5,843
$6,208



Components of Net Periodic Expense

Net periodic expense consisted of the following for the year ended December 31 (in thousands):
 
Defined Benefit
Pension Plan
Supplemental
Non-qualified Defined Benefit Plans

Non-pension Defined Benefit Postretirement Healthcare Plan
 201920182017201920182017201920182017
Service cost$365
$516
$545
$
$
$
$148
$193
$206
Interest cost2,410
2,194
2,341
114
108
116
186
179
176
Expected return on assets(3,405)(3,545)(3,591)





Amortization of prior service cost (credits)10
43
43



(336)(336)(336)
Recognized net actuarial loss (gain)1,221
2,063
1,230
65
103
87



Net periodic expense$601
$1,271
$568
$179
$211
$203
$(2)$36
$46

 
Defined Benefit
Pension Plan
Supplemental Non-qualified Defined Benefit Retirement PlansNon-pension Defined Benefit Postretirement Healthcare Plan
 201620152014201620152014201620152014
Service cost$606
$797
$704
$
$
$
$204
$233
$222
Interest cost2,499
2,956
2,991
122
142
146
187
214
241
Expected return on assets(3,632)(3,935)(3,702)





Amortization of prior service cost (credits)43
43
43



(337)(336)(335)
Recognized net actuarial loss (gain)1,995
2,196
940
82
93
45



Net periodic expense$1,511
$2,057
$976
$204
$235
$191
$54
$111
$128


For the years ended December 31, 2019 and 2018, service costs were recorded in Operations and maintenance expense while non-service costs were recorded in Other expense, on the Statements of Income. For the year ended December 31, 2017, service costs and non-service costs were recorded in Operations and maintenance expense. Because prior years’ costs were not considered material, they were not reclassified on the Statements of Income.


Accumulated Other Comprehensive Income (Loss)AOCI


AmountsFor defined benefit plans, amounts included in AOCI, after-tax, that have not yet been recognized as components of net periodic benefit cost at December 31 were as follows (in thousands):
 Defined Benefit Pension PlanSupplemental Non-qualified Defined Benefit PlansNon-pension Defined Benefit Postretirement Healthcare Plan
 201920182019201820192018
Net (gain) loss$
$
$812
$391
$
$
Total AOCI$
$
$812
$391
$
$
 Defined Benefit Pension PlanSupplemental Non-qualified Defined Benefit Retirement PlansNon-pension Defined Benefit Postretirement Healthcare Plan
 201620152016201520162015
Net loss$
$
$669
$672
$
$
Prior service cost





Total accumulated other comprehensive income (loss)$
$
$669
$672
$
$



The amounts in AOCI, regulatory assets or regulatory liabilities, after-tax, expected to be recognized as a component of net periodic benefit cost during calendar year 2017 are as follows (in thousands):
 
Defined Benefits
Pension Plan
Supplemental Non-qualified Defined Benefit Retirement PlansNon-pension Defined Benefit Postretirement Healthcare Plan
Net gain (loss)$799
$51
$
Prior service cost28

(218)
Total net periodic benefit cost expected to be recognized during calendar year 2017$827
$51
$(218)



Assumptions
Defined Benefit
Pension Plan
Supplemental Non-qualified Defined Benefit Retirement PlansNon-pension Defined Benefit Postretirement Healthcare Plan
Defined Benefit
Pension Plan
Supplemental Non-qualified Defined Benefit PlansNon-pension Defined Benefit Postretirement Healthcare Plan
201620152014201620152014201620152014201920182017201920182017201920182017
Weighted-average assumptions used to determine benefit obligations:  
Discount rate4.27%4.63%4.25%4.12%4.29%3.98%3.84%4.03%3.70%3.27%4.40%3.71%3.10%4.30%3.62%3.15%4.28%3.60%
Rate of increase in compensation levels3.47%3.57%3.86%N/A
N/A
N/A
N/A
N/A
N/A
3.49%3.52%3.43%N/A
N/A
N/A
N/A
N/A
N/A
  
Weighted-average assumptions used to determine net periodic benefit cost for plan year:  
Discount rate (a)
4.63%4.25%5.10%4.29%3.98%4.68%4.03%3.70%4.45%4.40%3.71%4.27%4.30%3.62%4.12%4.28%3.60%3.84%
Expected long-term rate of return on assets (b)
6.75%6.75%6.75%N/A
N/A
N/A
N/A
N/A
N/A
6.00%6.25%6.75%N/A
N/A
N/A
3.00%3.93%N/A
Rate of increase in compensation levels3.57%3.86%3.86%N/A
N/A
N/A
N/A
N/A
N/A
3.52%3.43%3.47%N/A
N/A
N/A
N/A
N/A
N/A
_____________________________

(a)The estimated discount rate for the merged Black Hills Corporation’s RetirementDefined Benefit Pension Plan is 4.27%3.27% for the calculation of the 20172020 net periodic pension costs.
(b)
The expected rate of return on plan assets is 6.75%5.25% for the calculation of the 20172020 net periodic pension cost.


The healthcare benefit obligation was determined at December 31 as follows:
 20192018
Trend Rate - Medical  
Pre-65 for next year6.40%6.70%
Pre-65 Ultimate trend rate4.50%4.50%
Trend Year2027
2027
   
Post-65 for next year4.92%4.94%
Post-65 Ultimate trend rate4.50%4.50%
Trend Year2028
2026

 20162015
Healthcare trend rate pre-65  
Trend for next year6.10%6.35%
Ultimate trend rate4.50%4.50%
Year Ultimate Trend Reached2024
2024
   
Healthcare trend rate post-65  
Trend for next year5.10%5.20%
Ultimate trend rate4.50%4.50%
Year Ultimate Trend Reached2023
2023



We do not pre-fund our post-retirement benefit plan. The table below shows the estimated impacts of an increase or decrease to our healthcare trend rate for our Retiree Health Care Plan (in thousands):
Change in Assumed Trend RateService and Interest CostsAccumulated Periodic Postretirement Benefit Obligation
1% increase$5
$125
1% decrease$(5)$(121)

Beginning in 2016, the Company changed the method used to estimate the service and interest cost components of the net periodic pension, supplemental non-qualified defined benefit and other postretirement benefit costs. The new method uses the spot yield curve approach to estimate the service and interest costs by applying the specific spot rates along the yield curve used to determine the benefit obligations to relevant projected cash outflows. Previously, those costs were determined using a single weighted-average discount rate. The change does not affect the measurement of the total benefit obligations as the change in service and interest costs offset the actuarial gains and losses recorded in other comprehensive income. The new method provides a more precise measure of interest and service costs by improving the correlation between the projected benefit cash flows and the discrete spot yield curve rates. We accounted for this change as a change in estimate beginning in the first quarter of 2016. See “Pension and Postretirement Benefit Obligations” within our Critical Accounting Policies in Item 7 on this Form 10-K for additional details.


The following benefit payments to employees, which reflect future service, are expected to be paid (in thousands):

 Defined Benefit Pension PlanSupplemental Non-qualified Defined Benefit PlansNon-Pension Defined Benefit Postretirement Healthcare Plan
2020$3,620
$321
$586
2021$3,766
$317
$622
2022$3,833
$315
$591
2023$3,951
$311
$522
2024$4,022
$308
$474
2025-2028$19,882
$1,142
$1,853

 Defined Benefit Pension PlanSupplemental Non-qualified Defined Benefit Retirement PlansDefined Benefit Postretirement Healthcare Plan
2017$3,946
$247
$541
2018$3,543
$243
$562
2019$3,669
$241
$577
2020$3,766
$237
$585
2021$3,883
$330
$570
2022-2026$20,663
$1,519
$2,456

Defined Contribution Plan

The Parent sponsors a 401(k) retirement savings plan in which our employees may participate. Participants may elect to invest up to 50% of their eligible compensation on a pre-tax or after-tax basis, up to a maximum amount established by the Internal Revenue Service. The plan provides for company matching contributions and company retirement contributions. Employer contributions vest at 20% per year and are fully vested when the participant has 5 years of service.


(9)    RELATED-PARTY TRANSACTIONS

Non-Cash Dividend to Parent

We recorded non-cash dividends to our Parent of approximately $53 million and $29 million in 2016 and 2015 respectively, and decreased the utility money pool note receivable, net for approximately $53 million and $29 million in 2016 and 2015, respectively.

Receivables and Payables

We have accounts receivable and accounts payable balances related to transactions with other BHC subsidiaries. These balances as of December 31 were as follows (in thousands):
 20162015
Receivable - affiliates$9,526
$6,734
Accounts payable - affiliates$31,799
$30,582



Money Pool Notes Receivable and Notes Payable

We have a Utility Money Pool Agreement (the Agreement) with BHC, Wyoming Electric and Black Hills Utility Holdings. Under the agreement, we may borrow from BHC however the Agreement restricts us from loaning funds to BHC or to any of BHCs’ non-utility subsidiaries. The Agreement does not restrict us from making dividends to BHC. Borrowings under the agreement bear interest at the weighted average daily cost of our parent company’s external borrowings as defined under the Agreement, or if there are no external funds outstanding on that date, then the rate will be the daily one month LIBOR rate plus 1.0%.

The cost of borrowing under the Utility Money Pool was 2.21% at December 31, 2016.

We had the following balances with the Utility Money Pool as of December 31 (in thousands):
 20162015
Notes receivable (payable), net$28,409
$76,813

Interest income relating to the Utility Money Pool for the years ended December 31, was as follows (in thousands):
 201620152014
Interest income$1,047
$1,153
$304

Interest expense allocation from Parent

BHC provides daily liquidity and cash management on behalf of all its subsidiaries. For the years ended December 31, 2016, 2015 and 2014, we were allocated $1.9 million, $2.1 million and $0.5 million, respectively, of interest expense allocations from BHC.

Other Balances and Transactions

We have the following Power Purchase and Transmission Services Agreements with affiliated entities:

An agreement, expiring September 3, 2028, with Wyoming Electric to acquire 15 MW of the facility output from Happy Jack. Under a separate inter-company agreement expiring on September 3, 2028, Wyoming Electric has agreed to sell up to 15 MW of the facility output from Happy Jack to us.

An agreement, expiring September 30, 2029, with Wyoming Electric to acquire 20 MW of the facility output from Silver Sage. Under a separate inter-company agreement expiring on September 30, 2029, Wyoming Electric has agreed to sell 20 MW of energy from Silver Sage to us.

A Generation Dispatch Agreement with Wyoming Electric that requires us to purchase all of Wyoming Electric’s excess energy.

Related-party Gas Transportation Service Agreement

On October 1, 2014, we entered into a gas transportation service agreement with Wyoming Electric in connection with gas supply for Cheyenne Prairie. The agreement is for a term of 40 years, in which we pay a monthly service and facility fee for firm and interruptible gas transportation.



Related-party Revenue and Purchases

We had the following related-party transactions for the years ended December 31 included in the corresponding captions in the accompanying Statements of Income:
 201620152014
 (in thousands)
Revenues:   
Energy sold to Wyoming Electric$2,440
$1,857
$1,894
Rent from electric properties$5,046
$4,772
$4,102
    
Purchases:   
Purchase of coal from WRDC$16,227
$16,401
$16,861
Purchase of excess energy from Wyoming Electric$252
$898
$3,033
Purchase of renewable wind energy from Wyoming Electric - Happy Jack$1,918
$1,578
$1,959
Purchase of renewable wind energy from Wyoming Electric - Silver Sage$3,300
$2,739
$3,200
Corporate support services from Parent, Black Hills Service Company and Black Hills Utility Holdings$25,748
$26,655
$32,332


(10)    SUPPLEMENTAL CASH FLOW INFORMATION

Years ended December 31,201620152014
 (in thousands)
Non-cash investing and financing activities -   
Property, plant and equipment acquired with accrued liabilities$5,521
$3,870
$4,234
Non-cash decrease to money pool note receivable, net$(52,500)$(28,501)$
Non-cash dividend to Parent company$52,500
$28,501
$
    
Supplemental disclosure of cash flow information:   
Cash (paid) refunded during the period for -   
Interest (net of amounts capitalized)$(21,320)$(21,913)$(19,573)
Income taxes$
$
$



(1113)    COMMITMENTS AND CONTINGENCIES


Power Purchase and Transmission Services Agreements


We have the following power purchase and transmission services agreements, not including related party agreements, as of December 31, 20162019 (see Note 914 for information on related party agreements):


A PPA with PacifiCorp, expiring on December 31, 2023,, which provides for the purchase by us of 50 MW of electric capacity and energy from PacifiCorp’s system. The price paid for the capacity and energy is based on the operating costs of one of PacifiCorp’s coal-fired electric generating plants;
plants.


A firm point-to-point transmission accessservice agreement with PacifiCorp that expires December 31, 2023. The agreement provides 50 MW of capacity and energy to deliverbe transmitted annually by PacifiCorp.

A PPA with PRPA to purchase up to 5012 MW of power on PacifiCorp’s transmission system to wholesale customers in the western regionwind energy through December 31, 2023; and

AnPRPA’s agreement with Thunder Creek for gas transport capacity, expiring on October 31, 2019.
Silver Sage. This agreement will expire September 30, 2029.


Costs incurred under these agreements were as follows for the years ended December 31 (in thousands):

ContractContract Type201920182017
PacifiCorpElectric capacity and energy$7,477
$13,681
$13,218
PacifiCorpTransmission access$1,741
$1,742
$1,671
Thunder CreekGas transport capacity$422
$633
$633
PRPAWind energy$688
$223
$

ContractContract Type201620152014
PacifiCorpElectric capacity and energy$12,221
$13,990
$13,943
PacifiCorpTransmission access$1,428
$1,213
$1,227
Thunder CreekGas transport capacity$633
$633
$633


Future Contractual Obligations


The following is a schedule of future minimum payments required under power purchase, transmission services facility and vehicle leases, and gas supply agreements (in thousands):


2020$6,531
2021$6,203
2022$6,203
2023$6,203
2024$
Thereafter$

2017$13,091
2018$6,388
2019$6,388
2020$6,388
2021$5,755
Thereafter$11,510


Long-Term Power Sales Agreements


We have the following significant long-term power sales agreements as of December 31, 2016:contracts with non-affiliated third-parties:


An agreement with MDU to supply up to a maximum of 25 MW on a cost reimbursement basis duringDuring periods of reduced production at Wygen III;III in which MDU owns a portion of the capacity, or during periods when Wygen III is off-line, MDU will be provided with 25 MW from our other generation facilities or from system purchases with reimbursement of costs by MDU. This agreement expires January 31, 2023.


AAn agreement to serve MDU capacity and energy up to a maximum of 50 MW in excess of Wygen III ownership. This agreement expires December 31, 2023. Additionally, we have firm network transmission access to deliver power on PacifiCorp’s system to Sheridan, Wyoming to serve our power sales contract with MDU through December 31, 2023, to supply up to a maximum of 50 MW;

An agreement with the Cityright to renew pursuant to the terms of Gillette to supply its first 23 MW on a cost reimbursement basis duringPacifiCorp’s transmission tariff.

During periods of reduced production at Wygen III.III in which the City of Gillette owns a portion of the capacity, or during periods when Wygen III is off-line, we will provide the City of Gillette with its first 23 MW from our other generating facilities or from system purchases with reimbursement of costs by the City of Gillette. Under this agreement, wewhich is renewed annually on September 3, South Dakota Electric will also provide the City of Gillette their operating component of spinning reserves;reserves.


A unit-contingentWe have an amended agreement, effective January 1, 2019, to supply up to 20 MW of energy and capacity sales agreement withto MEAN expiring on under a contract that expires May 31, 2023.2028. The terms of the contract run from June 1 through May 31 for each interval listed below. This contract is based on up to 10 MW from Neil Simpson II and up to 10 MW from Wygen IIIunit-contingent based on the availability of these plants. The energyour Neil Simpson II and Wygen III plants, with decreasing capacity purchase requirements decreasepurchased over the term of the agreement;agreement. The unit-contingent capacity amounts from Wygen III and



A PPA with MEAN, expiring May 31, 2023. This contract is unit-contingent on up to 10 MW from Neil Simpson II and up to 10 MW from Wygen III based on the availability of these plants. The capacity purchase requirements decrease over the term of the agreement.are as follows:

Contract YearsTotal Contract Capacity Contingent Capacity Amounts on Wygen III Contingent Capacity Amounts on Neil Simpson II
2019-202015
MW 10
MW 5
MW
2020-202215
MW 7
MW 8
MW
2022-202315
MW 8
MW 7
MW
2023-202810
MW 5
MW 5
MW

Effective January 1, 2017, we have an energy sales
An agreement with Cargill through December 31, 2021 to supplyprovide 50 MW of energy to Macquarie Energy, LLC during heavy and light load timing intervals.

Environmental Matters

We are subject to costs resulting from a number of federal, state and local laws and regulations which affect future planning and existing operations. They can result in increased capital expenditures, operating and other costs as a result of compliance, remediation and monitoring obligations. Due to the environmental issues discussed below, we may be required to modify, curtail, replace or cease operating certain facilities or operations to comply with statutes, regulations and other requirements of regulatory bodies.



Legal Proceedings


In the normal course of business, we are subject to various lawsuits, actions, proceedings, claims and other matters asserted under laws and regulations. We believe the amounts provided in the consolidated financial statements to satisfy alleged liabilities are adequate in light of the probable and estimable contingencies. However, there can be no assurance that the actual amounts required to satisfy alleged liabilities from various legal proceedings, claims and other matters discussed, and to comply with applicable laws and regulations will not exceed the amounts reflected in the consolidated financial statements.


In the normal course of business, we enter into agreements that include indemnification in favor of third parties, such as information technology agreements, purchase and sale agreements and lease contracts. We have also agreed to indemnify our directors, officers and employees in accordance with our articles of incorporation, as amended. Certain agreements do not contain any limits on our liability and therefore, it is not possible to estimate our potential liability under these indemnifications. In certain cases, we have recourse against third parties with respect to these indemnities. Further, we maintain insurance policies that may provide coverage against certain claims under these indemnities.


Environmental Matters


(14)    RELATED-PARTY TRANSACTIONS

Dividend to Parent

We are subjectdid not record any dividends in 2019. We recorded dividends to costs resulting from a numberour Parent of federal, state$36 million and local lawschanged the Utility Money Pool note by $36 million in 2018.

Receivables and regulations which affect future planningPayables

We have accounts receivable and existing operations. They can resultaccounts payable balances related to transactions with other BHC subsidiaries. These balances as of December 31 were as follows (in thousands):
 20192018
Accounts receivable from affiliates$7,838
$8,119
Accounts payable to affiliates$32,121
$25,804


Money Pool Notes Receivable and Notes Payable

We participate in increased capital expenditures, operating and other costs as a result of compliance, remediation and monitoring obligations. Due to the environmental issues discussed below,Utility Money Pool Agreement (the Agreement). Under the Agreement, we may borrow from the pool; however, the Agreement restricts the pool from loaning funds to BHC or to any of BHC’s non-utility subsidiaries. The Agreement does not restrict us from paying dividends to BHC. Borrowings under the Agreement bear interest at the weighted average daily cost of BHC’s external borrowings as defined under the Agreement, or if there are no external funds outstanding on that date, then the rate will be required to modify, curtail, replace or cease operating certain facilities or operations to complythe daily one-month LIBOR plus 1.0%. The cost of borrowing under the Utility Money Pool was 2.21% at December 31, 2019.

We had the following balances with statutes, regulations and other requirementsthe Utility Money Pool as of regulatory bodies.December 31 (in thousands):

 20192018
Money pool notes payable$57,585
$38,690

Air

Our generation facilities are subject to federal, state and local laws and regulationsInterest income (expense) relating to the protectionUtility Money Pool for the years ended December 31, was as follows (in thousands):
 201920182017
Interest income (expense)$(775)$(401)$272



Notes payable to Parent
 20192018
Notes payable to Parent (a)
$25,000
$
_______________
(a) Note bears interest at 4.51%, expired December 31, 2019, is eligible for annual renewal and was renewed through December 31, 2020. Interest payable related to this note was $0.2 million as of air quality. These lawsDecember 31, 2019.

Interest expense allocation from Parent

BHC provides daily liquidity and regulations cover, among other pollutants, carbon monoxide, SO2, NOx, mercury, hazardous air pollutants, particulate mattercash management on behalf of all its subsidiaries. For the years ended December 31, 2019, 2018 and GHG.2017, we were allocated $1.2 million, $1.3 million, and $1.4 million, respectively, of interest expense from BHC.

Other Balances and Transactions

We have the following Power generating facilities burning fossil fuels emit eachPurchase, Transmission Services, and Ground Lease Agreements with affiliated entities:

Wyoming Electric has a PPA with Happy Jack, expiring September 3, 2028, which provides up to 30 MW of wind energy. Under a separate intercompany agreement, Wyoming Electric sells 50% of the foregoing pollutantsfacility output to South Dakota Electric.

Wyoming Electric has a PPA with Silver Sage, expiring September 30, 2029, which provides up to 30 MW of wind energy. Under a separate intercompany agreement, Wyoming Electric sells 20 MW of energy from Silver Sage to South Dakota Electric.

A Generation Dispatch Agreement with Wyoming Electric that requires us to purchase all of Wyoming Electric’s excess energy.

A Wygen III Ground Lease with WDRC expiring in 2050 with 3 automatic renewal terms of 20 years each.

Related-party Gas Transportation Service Agreement

On October 1, 2014, we entered into a gas transportation service agreement with Wyoming Electric in connection with gas supply for Cheyenne Prairie. The agreement is for a term of 40 years, in which we pay a monthly service and therefore, are subject to substantial regulationfacility fee for firm and enforcement oversight by various governmental agencies.interruptible gas transportation.

Related-party Revenue and Purchases

We had the following related-party transactions for the years ended December 31 included in the corresponding captions in the accompanying Statements of Income:
 201920182017
 (in thousands)
Revenues:   
Energy sold to Wyoming Electric$1,333
$2,064
$2,481
Rent from electric properties$3,583
$3,634
$3,680
Horizon Point shared facility revenue$12,026
$11,211
$1,420
    
Fuel and purchased power:   
Purchases from WRDC mine$17,041
$17,532
$15,948
Purchase of excess energy from Wyoming Electric$856
$511
$601
Purchase of renewable wind energy from Wyoming Electric - Happy Jack$1,968
$1,942
$1,924
Purchase of renewable wind energy from Wyoming Electric - Silver Sage$3,579
$3,586
$3,290
Gas transportation service agreement with Wyoming Electric for firm and interruptible gas transportation$309
$364
$393

Title IVRelated-party Corporate Support

We had the following corporate support for the years ended December 31:
 201920182017
 (in thousands)
Corporate support services and fees from Parent, Black Hills Service Company and Black Hills Utility Holdings$39,667
$34,578
$27,869


Horizon Point Shared Facilities Agreement

South Dakota Electric and BHSC are parties to a shared facilities agreement, whereby BHSC is charged for the use of the Clean Air Act applies to several of our generation facilities, including the Neil Simpson II, Neil Simpson CT, Lange CT, Wygen IIIHorizon Point facility that is owned by South Dakota Electric and Wyodak plants. Title IV of the Clean Air Act created an SO2 allowance trading program as part of the federal acid rain program. Without purchasing additional allowances, we currently hold sufficient allowances to satisfy Title IV at all such plants through 2046.

The EPA issued the IndustrialBHSC provides certain operations and Commercial Boiler Regulations for Area Sources of Hazardous Air Pollutants, with updates which impose emission limits, fuel requirements and monitoring requirements. The rule had a compliance deadline of March 21, 2014. In anticipation of this rule, we suspended operationsmaintenance services at the Osage plant on October 1, 2010 and as a result of this rule, we suspended operations at the Ben French facility on August 31, 2012. We permanently retired Ben French, Osage and Neil Simpson I on March 21, 2014. The net book value of these plants was allowed regulatory accounting treatment and is recorded as a Regulatory Asset on the accompanying Balance Sheets.facility.


Solid Waste Disposal


Various materials used at our facilities are subject to disposal regulations. Our Osage plant, permanently retired on March 21, 2014, had an on-site ash impoundment that was near capacity. An application to close the impoundment was approved on April 13, 2012. Site closure work was completed in 2013 with the state providing closure certification in 2014. Post closure monitoring activities will continue for 30 years.

In September 2013, Osage also received a permit to close the small industrial rubble landfill. Site work was completed with the state providing closure certification in 2014. Post closure monitoring will continue for 30 years following the closure certification date.


(1215)    QUARTERLY HISTORICAL DATA (Unaudited)


We operate on a calendar year basis. The following table sets forth selected unaudited historical operating results data for each quarter (in thousands):
 
First
Quarter
Second
Quarter
Third
Quarter
Fourth
Quarter
2019    
Revenues$79,041
$69,246
$77,022
$65,910
Operating income$24,642
$17,310
$22,004
$19,981
Net income$15,497
$10,148
$13,743
$7,514
     
2018    
Revenues$73,815
$70,676
$78,067
$75,522
Operating income$20,364
$19,495
$21,428
$17,048
Net income$11,760
$11,125
$13,317
$9,443

 
First
Quarter
Second
Quarter
Third
Quarter
Fourth
Quarter
2016    
Operating revenues$68,642
$62,019
$66,728
$70,243
Operating income$20,780
$18,936
$22,410
$23,454
Net income$11,186
$9,806
$12,010
$12,136
     
2015    
Operating revenues$70,283
$68,038
$72,111
$67,432
Operating income$21,490
$21,143
$23,456
$21,825
Net income$10,403
$10,547
$12,287
$11,937




ITEM 9.CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND
FINANCIAL DISCLOSURE


None.


ITEM 9A.    CONTROLS AND PROCEDURES


Evaluation of Disclosure Controls and Procedures


Our Chief Executive Officer and Chief Financial Officer evaluated the effectiveness of our disclosure controls and procedures (as defined in Rules 13a-15(e) and 15d-15(e) of the Securities Exchange Act of 1934 (Exchange Act)) as of December 31, 2016.2019. Based on their evaluation, they have concluded that our disclosure controls and procedures are effective.


Our disclosure controls and procedures are designed to ensure that information required to be disclosed by us in the reports that we file or submit under the Security Exchange Act of 1934, as amended, is recorded, processed, summarized and reported, within the time periods specified in the Commission’s rules and forms, and that such information is accumulated and communicated to our management, including our Chief Executive Officer and Chief Financial Officer, as appropriate to allow timely decisions regarding required disclosure.


Changes in Internal Control over Financial Reporting

During the quarter ended December 31, 2019, there were no changes in the Company’s internal control over financial reporting (as defined in Rule 13a-15(f) under the Securities Exchange Act of 1934) that have materially affected, or are reasonably likely to materially affect, the Company’s internal control over financial reporting.
Management’s Report on Internal Control over Financial Reporting is presented on Page 27 of this Annual Report on Form 10-K.

During our fourth fiscal quarter, there have been no changes in our internal controls over financial reporting that have materially affected or are reasonably likely to materially affect our internal controls over financial reporting.


ITEM 9B.    OTHER INFORMATION


None.




ITEM 14.    PRINCIPAL ACCOUNTING FEES AND SERVICES


The following table sets forth the aggregate fees for services provided to us for the fiscal years ended December 31 by our independent registered public accounting firm, Deloitte & Touche LLP (in thousands):
Deloitte & Touche LLP2016201520192018
Audit Fees$216
$360
$510
$592
Tax Fees23
16
272
195
Audit-related fees

Total$239
$376
$782
$787


Audit Fees. Fees for professional services rendered for the audits of our financial statements, review of the interim financial statements included in quarterly reports and services that generally only the independent auditor can reasonably provide, such as comfort letters, statutory audits, consents and assistance with and review of documents filed with the Securities and Exchange Commission.


Tax Fees. Fees for services related to tax compliance, tax planning and advice including tax assistance with tax audits. These services include assistance regarding federal tax compliance and advice, review of tax returns, and federal tax planning.


The services performed by Deloitte & Touche LLP were pre-approved in accordance with the Black Hills Corporation Audit Committee’s pre-approval policy whereby the Audit Committee pre-approves all audit and permissible non-audit services provided by the independent registered public accountants. The Audit Committee annually reviews the services expected to be provided by the independent auditors and establishes pre-approval fee levels for each category of services to be provided, including audit, audit-related, tax and other services. Any service that is not included in the approved list of services must be separately pre-approved by the Audit Committee.





ITEM 15.EXHIBITS, FINANCIAL STATEMENT SCHEDULES


(a)1.Financial Statements
   
  
Financial statements required by Item 15 are listed in the index included in Item 8 of Part II.
   
 2.Schedules


Schedule II - Valuation and Qualifying Accounts for the years ended December 31, 2016, 20152019, 2018 and 20142017


  All other schedules have been omitted because of the absence of the conditions under which they are required or because the required information is included elsewhere in the financial statements incorporated by reference in this Form 10-K.


SCHEDULE II

BLACK HILLS POWER, INC.
VALUATION AND QUALIFYING ACCOUNTS
YEARS ENDED DECEMBER 31,
 
DescriptionBalance at beginning of yearAdditions charged to costs and expensesDeductions charged to costs and expensesBalance at end of year
 (in thousands)
Allowance for doubtful accounts:    
2016$207
$644
$(694)$157
2015$261
$602
$(656)$207
2014$220
$699
$(658)$261
Valuation and qualifying accounts are detailed within Note 1 of the Notes to the Financial Statements in this Annual Report on Form 10-K.





3.Exhibits
Exhibit NumberDescription
  
3.1*
  
3.2*Articles of Amendment to the Articles of Incorporation of the Registrant, as filed with the Secretary of State of the State of South Dakota on December 22, 2000 (filed as an exhibit to the Registrant’s Form 10-K for 2000).
3.3*
  
4.1*
  
10.1*
  
10.2*
10.3*Bond Purchase Agreement dated as of June 30, 2014 by and among Black Hills Power, Inc., New York Life Insurance Company, New York Life Insurance and Annuity Corporation, Teachers Insurance and Annuity Association of America, John Hancock Life Insurance Company (U.S.A.), John Hancock Life & Health Insurance Company, John Hancock Life Insurance Company of New York and United of Omaha Life Insurance Company (filed as Exhibit 10.1 to the Registrant’s Form 8-K filed on July 2, 2014).
  
31.1
  
31.2
  
32.1
  
32.2
  
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101.LABXBRL Taxonomy Extension Label Linkbase Document
101.PREXBRL Taxonomy Extension Presentation Linkbase Document
104Cover Page Interactive Data File (formatted as inline XBRL and contained in Exhibit 101)
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*Previously filed as part of the filing indicated and incorporated by reference herein.

(a)See (a) 3. Exhibits above.
(b)See (a) 2. Schedules above.


SUPPLEMENTAL INFORMATION TO BE FURNISHED WITH REPORTS FILED PURSUANT TO SECTION 15(d) OF THE ACT BY REGISTRANTS WHICH HAVE NOT REGISTERED SECURITIES PURSUANT TO SECTION 12 OF THE ACT.


The Registrant is not required to send an Annual Report or Proxy to its sole security holder and parent company, Black Hills Corporation.




ITEM 16.FORM 10-K SUMMARY


None.




SIGNATURES


Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.
  BLACK HILLS POWER, INC.
   
  By/s/ DAVIDLINDEN R. EMERYEVANS
  DavidLinden R. Emery,Evans, Chairman, President and Chief Executive Officer
  Chief Executive Officer
Dated:February 28, 201718, 2020 


Pursuant to the requirements of the Securities Exchange Act of 1934, this report has been signed below by the following persons on behalf of the Registrant and in the capacities and on the dates indicated.


/s/ DAVIDLINDEN R. EMERYEVANSDirector andFebruary 28, 201718, 2020
DavidLinden R. Emery,Evans, Chairman, President andPrincipal Executive Officer 
Chief Executive Officer  
   
/s/ RICHARD W. KINZLEYDirector andFebruary 28, 201718, 2020
Richard W. Kinzley, Senior Vice PresidentPrincipal Financial and 
and Chief Financial OfficerAccounting Officer 
   
/s/ LINDEN R. EVANSDirectorFebruary 28, 2017
Linden R. Evans
/s/ BRIAN G. IVERSONDirectorFebruary 28, 201718, 2020
Brian G. Iverson  


INDEX TO EXHIBITS


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Exhibit NumberDescription
3.1*Restated Articles of Incorporation of the Registrant (filed as an exhibit to the Registrant’s Form 8-K dated June 7, 1994 (No. 1-7978)).
3.2*Articles of Amendment to the Articles of Incorporation of the Registrant, as filed with the Secretary of State of the State of South Dakota on December 22, 2000 (filed as an exhibit to the Registrant’s Form 10-K for 2000).
3.3*Bylaws of the Registrant (filed as an exhibit to the Registrant’s Registration Statement on Form S-8 dated July 13, 1999).
4.1*Restated and Amended Indenture of Mortgage and Deed of Trust of Black Hills Corporation (now called Black Hills Power, Inc.) dated as of September 1, 1999 (filed as Exhibit 4.19 to the Registrant’s Post-Effective Amendment No. 1 to the Registrant’s Registration Statement on Form S-3 (No. 333-150669-01)). First Supplemental Indenture, dated as of August 13, 2002, between Black Hills Power, Inc. and The Bank of New York Mellon (as successor to J.P. Morgan Chase Bank), as Trustee (filed as Exhibit 4.20 to the Registrant’s Post-Effective Amendment No. 1 to the Registrant’s Registration Statement on Form S-3 (No. 333-150669-01)). Second Supplemental Indenture, dated as of October 27, 2009, between Black Hills Power, Inc. and The Bank of New York Mellon (filed as Exhibit 4.21 to the Registration Statement on Form S-3 (No. 333-150669-01)). Third Supplemental Indenture, dated as of October 1, 2014, between Black Hills Power, Inc., and The Bank of New York Mellon (filed as Exhibit 10.1 to the Registrant’s Form 8-K filed on October 2, 2014).
10.1*Restated and Amended Coal Supply Agreement for NS II dated February 12, 1993 (filed as Exhibit 10.1 to the Registrant’s Post-Effective Amendment No. 1 to the Registrant’s Registration Statement on Form S-3 (No. 333-150669-01)).
10.2*Second Restated and Amended Power Sales Agreement dated September 29, 1997, between PacifiCorp and Black Hills Power, Inc. (filed as Exhibit 10.2 to the Registrant’s Post-Effective Amendment No. 1 to the Registrant’s Registration Statement on Form S-3 (No. 333-150669-01)).
10.3*Bond Purchase Agreement dated as of June 30, 2014 by and among Black Hills Power, Inc., New York Life Insurance Company, New York Life Insurance and Annuity Corporation, Teachers Insurance and Annuity Association of America, John Hancock Life Insurance Company (U.S.A.), John Hancock Life & Health Insurance Company, John Hancock Life Insurance Company of New York and United of Omaha Life Insurance Company (filed as Exhibit 10.1 to the Registrant’s Form 8-K filed on July 2, 2014).
31.1Certification of Chief Executive Officer pursuant to Rule13a-14(a) of the Securities Exchange Act of 1934, as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.
31.2Certification of Chief Financial Officer pursuant to Rule13a-14(a) of the Securities Exchange Act of 1934, as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.
32.1Certification of Chief Executive Officer Pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.
32.2Certification of Chief Financial Officer Pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.
101Financial Statements for XBRL Format
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*Previously filed as part of the filing indicated and incorporated by reference herein.


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