Edgar Cover
Edgar Cover - USD ($) | 12 Months Ended | |
Dec. 31, 2020 | Jun. 30, 2020 | |
Cover [Abstract] | ||
Document Type | 10-K | |
Document Annual Report | true | |
Document Period End Date | Dec. 31, 2020 | |
Current Fiscal Year End Date | --12-31 | |
Document Transition Report | false | |
Entity File Number | 333-192954 | |
Entity Registrant Name | OGLETHORPE POWER CORP | |
Entity Incorporation, State or Country Code | GA | |
Entity Tax Identification Number | 58-1211925 | |
Entity Address, Address Line One | 2100 East Exchange Place | |
Entity Address, City or Town | Tucker | |
Entity Address, State or Province | GA | |
Entity Address, Postal Zip Code | 30084-5336 | |
City Area Code | 770 | |
Local Phone Number | 270-7600 | |
Entity Well-known Seasoned Issuer | No | |
Entity Voluntary Filers | No | |
Entity Current Reporting Status | No | |
Entity Interactive Data Current | Yes | |
Entity Filer Category | Non-accelerated Filer | |
Entity Small Business | false | |
Entity Emerging Growth Company | false | |
ICFR Auditor Attestation Flag | false | |
Entity Shell Company | false | |
Entity Public Float | $ 0 | |
Entity Common Stock, Shares Outstanding | 0 | |
Entity Central Index Key | 0000788816 | |
Amendment Flag | false | |
Document Fiscal Year Focus | 2020 | |
Document Fiscal Period Focus | FY |
CONSOLIDATED STATEMENTS OF REVE
CONSOLIDATED STATEMENTS OF REVENUES AND EXPENSES - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | |
Operating revenues: | |||
Total operating revenues | $ 1,377,618 | $ 1,430,292 | $ 1,480,113 |
Operating expenses: | |||
Fuel | 360,254 | 440,214 | 502,904 |
Production | 427,808 | 410,328 | 417,391 |
Depreciation and amortization | 248,888 | 243,512 | 233,284 |
Purchased power | 68,484 | 68,556 | 63,468 |
Accretion | 54,475 | 50,473 | 38,090 |
Total operating expenses | 1,159,909 | 1,213,083 | 1,255,137 |
Operating margin | 217,709 | 217,209 | 224,976 |
Other income: | |||
Investment income | 43,294 | 59,182 | 60,055 |
Amortization of deferred gains | 1,789 | 1,788 | 1,788 |
Allowance for equity funds used during construction | 374 | 771 | 1,006 |
Other | 5,238 | 2,448 | 5,413 |
Total other income | 50,695 | 64,189 | 68,262 |
Interest charges: | |||
Interest expense | 409,145 | 403,244 | 381,242 |
Allowance for debt funds used during construction | (207,972) | (187,954) | (151,643) |
Amortization of debt discount and expense | 11,336 | 11,647 | 12,440 |
Net interest charges | 212,509 | 226,937 | 242,039 |
Net margin | 55,895 | 54,461 | 51,199 |
Members | |||
Operating revenues: | |||
Total operating revenues | 1,377,010 | 1,429,852 | 1,479,379 |
Non-Members | |||
Operating revenues: | |||
Total operating revenues | $ 608 | $ 440 | $ 734 |
CONSOLIDATED BALANCE SHEETS
CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019 |
Electric plant: | ||
In service | $ 9,394,112 | $ 9,209,983 |
Right-of-use assets--finance leases | 302,732 | 302,732 |
Less: Accumulated provision for depreciation | (4,968,294) | (4,833,025) |
Net in service | 4,728,550 | 4,679,690 |
Nuclear fuel, at amortized cost | 358,728 | 359,270 |
Construction work in progress | 5,783,579 | 4,816,896 |
Total electric plant | 10,870,857 | 9,855,856 |
Investments and funds: | ||
Nuclear decommissioning trust fund | 598,181 | 511,339 |
Investment in associated companies | 74,844 | 73,318 |
Long-term investments | 518,065 | 254,864 |
Restricted investments | 306,601 | 461,757 |
Other | 29,189 | 26,422 |
Total investments and funds | 1,526,880 | 1,327,700 |
Current assets: | ||
Cash and cash equivalents | 405,511 | 448,612 |
Restricted short-term investments | 180,986 | 71,833 |
Receivables | 152,466 | 166,429 |
Inventories, at average cost | 280,289 | 277,729 |
Prepayments and other current assets | 33,839 | 9,862 |
Total current assets | 1,053,091 | 974,465 |
Deferred charges and other assets: | ||
Regulatory assets | 731,438 | 763,512 |
Prepayments to Georgia Power Company | 37,601 | 48,052 |
Other | 20,289 | 20,528 |
Total deferred charges | 789,328 | 832,092 |
Total assets | 14,240,156 | 12,990,113 |
Capitalization: | ||
Patronage capital and membership fees | 1,072,642 | 1,016,747 |
Long-term debt | 10,298,385 | 9,403,847 |
Obligations under finance leases | 68,876 | 75,649 |
Other | 26,861 | 25,196 |
Total capitalization | 11,466,764 | 10,521,439 |
Current liabilities: | ||
Long-term debt and finance leases due within one year | 208,649 | 217,440 |
Short-term borrowings | 383,498 | 282,370 |
Accounts payable | 162,249 | 165,049 |
Accrued interest | 72,434 | 65,895 |
Member power bill prepayments, current | 46,068 | 77,066 |
Other current liabilities | 68,932 | 49,443 |
Total current liabilities | 941,830 | 857,263 |
Deferred credits and other liabilities: | ||
Asset retirement obligations | 1,135,983 | 1,070,640 |
Member power bill prepayments, non-current | 98,113 | 134,396 |
Regulatory liabilities | 566,399 | 364,241 |
Other | 31,067 | 42,134 |
Total deferred credits and other liabilities | 1,831,562 | 1,611,411 |
Total equity and liabilities | 14,240,156 | 12,990,113 |
Commitments and Contingencies (Notes 1, 7, 10, 11 and 12) |
CONSOLIDATED STATEMENTS OF CAPI
CONSOLIDATED STATEMENTS OF CAPITALIZATION - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019 |
Secured Long-term debt: | ||
Total Secured Long-term debt | $ 10,619,826 | $ 9,726,428 |
Obligations under finance leases | 75,649 | 81,730 |
Obligation under Rocky Mountain transactions | 26,861 | 25,196 |
Patronage capital and membership fees | 1,072,642 | 1,016,747 |
Subtotal | 11,794,978 | 10,850,101 |
Less: long-term debt and finance leases due within one year | (208,649) | (217,440) |
Less: unamortized debt issuance costs | (102,914) | (100,680) |
Less: unamortized bond discounts on long-term debt | (16,651) | (10,542) |
Total capitalization | 11,466,764 | 10,521,439 |
Federal Financing Bank (FFB) | First mortgage notes payable to the Federal Financing Bank at interest rates varying from 1.03% to 8.21% (average rate of 3.65% at December 31, 2020) due in quarterly installments through 2046 | ||
Secured Long-term debt: | ||
Total Secured Long-term debt | 2,430,810 | 2,526,867 |
Federal Financing Bank (FFB) | First mortgage notes payable to the Federal Financing Bank at interest rates varying from 1.44% to 3.87% (average rate of 2.87% at December 31, 2020) due in quarterly installments through 2044 | ||
Secured Long-term debt: | ||
Total Secured Long-term debt | 3,554,205 | 3,013,348 |
National Rural Utilities Cooperative Finance Corporation (CFC) | First mortgage notes payable to National Rural Utilities Cooperative Finance Corporation at interest rate of 4.90% due in quarterly installments through 2020 | ||
Secured Long-term debt: | ||
Total Secured Long-term debt | 0 | 391 |
Public | First mortgage bonds payable: Series 2006 First Mortgage Bonds, 5.534%, due 2031 through 2035 | ||
Secured Long-term debt: | ||
Total Secured Long-term debt | 300,000 | 300,000 |
Public | First mortgage bonds payable: Series 2007 First Mortgage Bonds, 6.191%, due 2024 through 2031 | ||
Secured Long-term debt: | ||
Total Secured Long-term debt | 500,000 | 500,000 |
Public | First mortgage bonds payable: Series 2009B First Mortgage Bonds, 5.95%, due 2039 | ||
Secured Long-term debt: | ||
Total Secured Long-term debt | 400,000 | 400,000 |
Public | First mortgage bonds payable: Series 2009 Clean renewable energy bond, 1.81%, due 2024 | ||
Secured Long-term debt: | ||
Total Secured Long-term debt | 4,041 | 5,052 |
Public | First mortgage bonds payable: Series 2010A First Mortgage Bonds, 5.375% due 2040 | ||
Secured Long-term debt: | ||
Total Secured Long-term debt | 450,000 | 450,000 |
Public | First mortgage bonds payable: Series 2011A First Mortgage Bonds, 5.25% due 2050 | ||
Secured Long-term debt: | ||
Total Secured Long-term debt | 300,000 | 300,000 |
Public | First mortgage bonds payable: Series 2012A First Mortgage Bonds, 4.20% due 2042 | ||
Secured Long-term debt: | ||
Total Secured Long-term debt | 250,000 | 250,000 |
Public | First mortgage bonds payable: Series 2014A First Mortgage Bonds, 4.55% due 2044 | ||
Secured Long-term debt: | ||
Total Secured Long-term debt | 250,000 | 250,000 |
Public | First mortgage bonds payable: Series 2016A First Mortgage Bonds, 4.25% due 2046 | ||
Secured Long-term debt: | ||
Total Secured Long-term debt | 250,000 | 250,000 |
Public | First Mortgage Bonds Payable: Series 2018A First Mortgage Bonds, 5.05% Due 2048 | ||
Secured Long-term debt: | ||
Total Secured Long-term debt | 500,000 | 500,000 |
Public | First Mortgage Bonds Payable Series 2020A First Mortgage Bonds, 3.75% Due 2048 | ||
Secured Long-term debt: | ||
Total Secured Long-term debt | 450,000 | 0 |
Georgia Development Authorities | First mortgage notes issued in connection with the sale of pollution control revenue bonds: 2009A Heard and Monroe, and 2009B Monroe, Weekly rate bonds, 1.80%, due 2030 through 2038 | ||
Secured Long-term debt: | ||
Total Secured Long-term debt | 112,055 | 112,055 |
Georgia Development Authorities | First mortgage notes issued in connection with the sale of pollution control revenue bonds: 2010A Burke and Monroe, and 2010B Burke, Weekly rate bonds, 1.71% to 1.82%, due 2036 through 2037 | ||
Secured Long-term debt: | ||
Total Secured Long-term debt | 133,550 | 133,550 |
Georgia Development Authorities | First mortgage notes issued in connection with the sale of pollution control revenue bonds: 2013A Appling, Burke and Monroe, Term rate bonds, 2.40% through April 1, 2020, due 2038 through 2040 | ||
Secured Long-term debt: | ||
Total Secured Long-term debt | 212,760 | 212,760 |
Georgia Development Authorities | First mortgage notes issued in connection with the sale of pollution control revenue bonds: Series 2017 A Burke, Heard, Monroe and 2017B Burke, Indexed put bonds - weekly reset, 2.81% due 2040 through 2045 | ||
Secured Long-term debt: | ||
Total Secured Long-term debt | 122,620 | 122,620 |
Georgia Development Authorities | First mortgage notes issued in connection with the sale of pollution control revenue bonds: Series 2017 C, D Burke, Remarketed in 2018 to fixed rate bonds, 4.125%, due 2041 through 2045 | ||
Secured Long-term debt: | ||
Total Secured Long-term debt | 200,000 | 200,000 |
Georgia Development Authorities | First mortgage notes issued in connection with the sale of pollution control revenue bonds: Series 2017E Burke, Remarketed in 2018 to term rate bonds, 3.25% through February 3, 2025, due 2041 through 2045 | ||
Secured Long-term debt: | ||
Total Secured Long-term debt | 100,000 | 100,000 |
Georgia Development Authorities | First mortgage notes issued in connection with the sale of pollution control revenue bonds: Series 2017 F Burke, Remarketed in 2018 to term rate bonds, 3.00% through February 1, 2023, due 2041 through 2045 | ||
Secured Long-term debt: | ||
Total Secured Long-term debt | $ 99,785 | $ 99,785 |
CONSOLIDATED STATEMENTS OF CA_2
CONSOLIDATED STATEMENTS OF CAPITALIZATION (Parenthetical) | Dec. 31, 2020 |
Federal Financing Bank (FFB) | First mortgage notes payable to the Federal Financing Bank at interest rates varying from 1.03% to 8.21% (average rate of 3.65% at December 31, 2020) due in quarterly installments through 2046 | |
Secured Long-term debt: | |
Interest rate, average rate (as a percent) | 3.65% |
Federal Financing Bank (FFB) | First mortgage notes payable to the Federal Financing Bank at interest rates varying from 1.03% to 8.21% (average rate of 3.65% at December 31, 2020) due in quarterly installments through 2046 | Minimum | |
Secured Long-term debt: | |
Interest rate (as a percent) | 1.03% |
Federal Financing Bank (FFB) | First mortgage notes payable to the Federal Financing Bank at interest rates varying from 1.03% to 8.21% (average rate of 3.65% at December 31, 2020) due in quarterly installments through 2046 | Maximum | |
Secured Long-term debt: | |
Interest rate (as a percent) | 8.21% |
Federal Financing Bank (FFB) | First mortgage notes payable to the Federal Financing Bank at interest rates varying from 1.44% to 3.87% (average rate of 2.87% at December 31, 2020) due in quarterly installments through 2044 | |
Secured Long-term debt: | |
Interest rate, average rate (as a percent) | 2.87% |
Federal Financing Bank (FFB) | First mortgage notes payable to the Federal Financing Bank at interest rates varying from 1.44% to 3.87% (average rate of 2.87% at December 31, 2020) due in quarterly installments through 2044 | Minimum | |
Secured Long-term debt: | |
Interest rate (as a percent) | 1.44% |
Federal Financing Bank (FFB) | First mortgage notes payable to the Federal Financing Bank at interest rates varying from 1.44% to 3.87% (average rate of 2.87% at December 31, 2020) due in quarterly installments through 2044 | Maximum | |
Secured Long-term debt: | |
Interest rate (as a percent) | 3.87% |
National Rural Utilities Cooperative Finance Corporation (CFC) | First mortgage notes payable to National Rural Utilities Cooperative Finance Corporation at interest rate of 4.90% due in quarterly installments through 2020 | Maximum | |
Secured Long-term debt: | |
Interest rate (as a percent) | 4.90% |
Public | First mortgage bonds payable: Series 2006 First Mortgage Bonds, 5.534%, due 2031 through 2035 | |
Secured Long-term debt: | |
Interest rate (as a percent) | 5.534% |
Public | First mortgage bonds payable: Series 2007 First Mortgage Bonds, 6.191%, due 2024 through 2031 | |
Secured Long-term debt: | |
Interest rate (as a percent) | 6.191% |
Public | First mortgage bonds payable: Series 2009B First Mortgage Bonds, 5.95%, due 2039 | |
Secured Long-term debt: | |
Interest rate (as a percent) | 5.95% |
Public | First mortgage bonds payable: Series 2009 Clean renewable energy bond, 1.81%, due 2024 | |
Secured Long-term debt: | |
Interest rate (as a percent) | 1.81% |
Public | First mortgage bonds payable: Series 2010A First Mortgage Bonds, 5.375% due 2040 | |
Secured Long-term debt: | |
Interest rate (as a percent) | 5.375% |
Public | First mortgage bonds payable: Series 2011A First Mortgage Bonds, 5.25% due 2050 | |
Secured Long-term debt: | |
Interest rate (as a percent) | 5.25% |
Public | First mortgage bonds payable: Series 2012A First Mortgage Bonds, 4.20% due 2042 | |
Secured Long-term debt: | |
Interest rate (as a percent) | 4.20% |
Public | First mortgage bonds payable: Series 2014A First Mortgage Bonds, 4.55% due 2044 | |
Secured Long-term debt: | |
Interest rate (as a percent) | 4.55% |
Public | First mortgage bonds payable: Series 2016A First Mortgage Bonds, 4.25% due 2046 | |
Secured Long-term debt: | |
Interest rate (as a percent) | 4.25% |
Public | First Mortgage Bonds Payable: Series 2018A First Mortgage Bonds, 5.05% Due 2048 | |
Secured Long-term debt: | |
Interest rate (as a percent) | 5.05% |
Public | First Mortgage Bonds Payable Series 2020A First Mortgage Bonds, 3.75% Due 2048 | |
Secured Long-term debt: | |
Interest rate (as a percent) | 3.75% |
Georgia Development Authorities | First mortgage notes issued in connection with the sale of pollution control revenue bonds: 2009A Heard and Monroe, and 2009B Monroe, Weekly rate bonds, 1.80%, due 2030 through 2038 | |
Secured Long-term debt: | |
Interest rate (as a percent) | 0.08% |
Georgia Development Authorities | First mortgage notes issued in connection with the sale of pollution control revenue bonds: 2010A Burke and Monroe, and 2010B Burke, Weekly rate bonds, 1.71% to 1.82%, due 2036 through 2037 | Minimum | |
Secured Long-term debt: | |
Interest rate (as a percent) | 0.09% |
Georgia Development Authorities | First mortgage notes issued in connection with the sale of pollution control revenue bonds: 2010A Burke and Monroe, and 2010B Burke, Weekly rate bonds, 1.71% to 1.82%, due 2036 through 2037 | Maximum | |
Secured Long-term debt: | |
Interest rate (as a percent) | 0.16% |
Georgia Development Authorities | First mortgage notes issued in connection with the sale of pollution control revenue bonds: 2013A Appling, Burke and Monroe, Term rate bonds, 2.40% through April 1, 2020, due 2038 through 2040 | |
Secured Long-term debt: | |
Interest rate (as a percent) | 1.50% |
Georgia Development Authorities | First mortgage notes issued in connection with the sale of pollution control revenue bonds: Series 2017 A Burke, Heard, Monroe and 2017B Burke, Indexed put bonds - weekly reset, 2.81% due 2040 through 2045 | |
Secured Long-term debt: | |
Interest rate (as a percent) | 1.19% |
Georgia Development Authorities | First mortgage notes issued in connection with the sale of pollution control revenue bonds: Series 2017 C, D Burke, Remarketed in 2018 to fixed rate bonds, 4.125%, due 2041 through 2045 | |
Secured Long-term debt: | |
Interest rate (as a percent) | 4.125% |
Georgia Development Authorities | First mortgage notes issued in connection with the sale of pollution control revenue bonds: Series 2017E Burke, Remarketed in 2018 to term rate bonds, 3.25% through February 3, 2025, due 2041 through 2045 | |
Secured Long-term debt: | |
Interest rate (as a percent) | 3.25% |
Georgia Development Authorities | First mortgage notes issued in connection with the sale of pollution control revenue bonds: Series 2017 F Burke, Remarketed in 2018 to term rate bonds, 3.00% through February 1, 2023, due 2041 through 2045 | |
Secured Long-term debt: | |
Interest rate (as a percent) | 3.00% |
CONSOLIDATED STATEMENTS OF CASH
CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | |
Cash flows from operating activities: | |||
Net margin | $ 55,895 | $ 54,461 | $ 51,199 |
Adjustments to reconcile net margin to net cash provided by operating activities: | |||
Depreciation and amortization, including nuclear fuel | 376,639 | 377,853 | 371,234 |
Accretion cost | 54,475 | 50,473 | 38,090 |
Amortization of deferred gains | (1,789) | (1,788) | (1,788) |
Allowance for equity funds used during construction | (374) | (771) | (1,006) |
Deferred outage costs | (38,278) | (34,505) | (31,863) |
(Gain) loss on sale of investments | (19,779) | (6,058) | 4,871 |
Regulatory deferral of costs associated with nuclear decommissioning | (10,691) | (23,982) | (26,511) |
Other | (5,587) | (1,097) | (5,676) |
Change in operating assets and liabilities: | |||
Receivables | (3,659) | 24,251 | 8,424 |
Inventories | (2,409) | (18,597) | 5,487 |
Prepayments and other current assets | (23,754) | (1,992) | 4,544 |
Accounts payable | 1,504 | (27,668) | 1,360 |
Accrued interest | 6,539 | 4,924 | (18,539) |
Accrued and withheld taxes | 33,588 | 2,943 | (21,351) |
Other current liabilities | 9,439 | (24,069) | 25,723 |
Member power bill prepayments | (67,281) | (68,245) | 69,921 |
Rate management program collections | 146,917 | 45,228 | 15,578 |
Total adjustments | 455,500 | 296,900 | 438,498 |
Net cash provided by operating activities | 511,395 | 351,361 | 489,697 |
Cash flows from investing activities: | |||
Property additions | (1,335,380) | (1,255,188) | (1,185,367) |
Activity in nuclear decommissioning trust fund – Purchases | (578,610) | (374,338) | (457,909) |
Activity in nuclear decommissioning trust fund - Proceeds | 570,294 | 365,871 | 449,895 |
Decrease in restricted investments | 46,003 | 119,568 | 229,751 |
Activity in other long-term investments – Purchases | (425,628) | (251,077) | (207,670) |
Activity in other long-term investments - Proceeds | 186,219 | 178,172 | 176,717 |
Other | 7,982 | (21,493) | 9,144 |
Net cash used in investing activities | (1,529,120) | (1,238,485) | (985,439) |
Cash flows from financing activities: | |||
Long-term debt proceeds | 2,221,685 | 1,266,950 | 813,028 |
Long-term debt payments | (1,334,368) | (523,691) | (201,354) |
Increase (decrease) in short-term borrowings, net | 101,128 | (154,257) | 246,001 |
Other | (13,821) | (5,884) | (7,010) |
Net cash provided by financing activities | 974,624 | 583,118 | 850,665 |
Net (decrease) increase in cash and cash equivalents | (43,101) | (304,006) | 354,923 |
Cash and cash equivalents at beginning of period | 448,612 | 752,618 | 397,695 |
Cash and cash equivalents at end of period | 405,511 | 448,612 | 752,618 |
Cash paid for – | |||
Interest (net of amounts capitalized) | 193,063 | 208,892 | 245,085 |
Supplemental disclosure of non-cash investing and financing activities: | |||
Change in asset retirement obligations | 18,709 | 5,282 | 248,608 |
Accrued property additions at end of period | 89,640 | 94,492 | 121,557 |
Interest paid-in-kind | $ 0 | $ 67,028 | $ 59,137 |
CONSOLIDATED STATEMENTS OF PATR
CONSOLIDATED STATEMENTS OF PATRONAGE CAPITAL AND MEMBERSHIP FEES AND ACCUMULATED OTHER COMPREHENSIVE (DEFICIT) MARGIN - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended | |||||
Dec. 31, 2020 | Mar. 31, 2020 | Dec. 31, 2019 | Mar. 31, 2019 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | |
Increase (Decrease) in Members' Capital | |||||||
Net margin | $ (1,942) | $ 23,204 | $ 3,196 | $ 23,596 | $ 55,895 | $ 54,461 | $ 51,199 |
Patronage Capital And Membership Fees | |||||||
Increase (Decrease) in Members' Capital | |||||||
Beginning balance | $ 1,016,747 | $ 962,286 | 1,016,747 | 962,286 | 911,087 | ||
Net margin | 55,895 | 54,461 | 51,199 | ||||
Ending balance | $ 1,072,642 | $ 1,016,747 | $ 1,072,642 | $ 1,016,747 | $ 962,286 |
Summary of significant accounti
Summary of significant accounting policies | 12 Months Ended |
Dec. 31, 2020 | |
Accounting Policies [Abstract] | |
Summary of significant accounting policies | Summary of significant accounting policies: a. Business description Oglethorpe Power Corporation is an electric membership corporation incorporated in 1974 and headquartered in metropolitan Atlanta, Georgia that operates on a not-for-profit basis. We are owned by 38 retail electric distribution cooperative members in Georgia. We provide wholesale electric power from a combination of owned and co-owned generating units of which our ownership share totals 7,125 megawatts of summer planning reserve capacity. We also manage and operate Smarr EMC which owns 737 megawatts of summer planning reserve capacity. In addition, we supply financial and management services to Green Power EMC, which purchases energy from renewable energy facilities totaling 320 megawatts of capacity, including 288 megawatts sourced by solar energy. Georgia Power Company is a co-owner and the operating agent of our nuclear and coal-fired generating units. Our members in turn distribute energy on a retail basis to approximately 4.3 million people. b. Basis of accounting Our consolidated financial statements include our accounts and the accounts of our majority-owned and controlled subsidiary. We have determined that there are no accounts of variable interest entities for which we are the primary beneficiary. We have eliminated any intercompany profits and transactions in consolidation. We follow generally accepted accounting principles in the United States. We maintain our accounts in accordance with the Uniform System of Accounts of the Federal Energy Regulatory Commission as modified and adopted by the Rural Utilities Service. We also apply the accounting guidance for regulated operations. The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of December 31, 2020 and 2019 and the reported amounts of revenues and expenses for each of the three years in the period ended December 31, 2020. Examples of estimates used include items related to our asset retirement obligations. Accounting for asset retirement and environmental obligations requires legal obligations associated with the retirement of long-lived assets to be recognized at fair value when incurred and capitalized as part of the related long-lived asset. In the absence of quoted market prices, we estimate the fair value of our asset retirement obligations using present value techniques, in which estimates of future cash flows associated with retirement activities are discounted using a credit-adjusted risk-free rate. Estimating the amount and timing of future expenditures includes, among other things, making projections of when assets will be retired and ultimately decommissioned, the amount of decommissioning costs, and how costs will escalate with inflation. Actual results could differ from those estimates. c. Patronage capital and membership fees We are organized and operate as a cooperative. Our members paid a total of $190 in membership fees. Patronage capital includes retained net margin. Any excess of revenues over expenditures from operations is treated as an advance of capital by our members and is allocated to each member on the basis of their fixed percentage capacity cost responsibilities in our generation. Any distributions of patronage capital are subject to the discretion of our board of directors, subject to first mortgage indenture requirements. Under our first mortgage indenture, we are prohibited from making any distribution of patronage capital to our members if, at the time of or after giving effect to, (i) an event of default exists under the indenture, (ii) our equity as of the end of the immediately preceding fiscal quarter is less than 20% of our total long-term debt and equities, or (iii) the aggregate amount expended for distributions on or after the date on which our equity first reaches 20% of our total long-term debt and equities exceeds 35% of our aggregate net margins earned after such date. This last restriction, however will not apply if, after giving effect to such distribution, our equity as of the end of the immediately preceding fiscal quarter is not less than 30% of our long-term debt and equities. d. Margin policy We are required under our first mortgage indenture to produce a margins for interest ratio of at least 1.10 for each fiscal year. For the years 2020, 2019 and 2018, we achieved a margins for interest ratio of 1.14. e. Revenue recognition As an electric membership cooperative, our principal business is providing wholesale electric service to our members. Our operating revenues are derived primarily from wholesale power contracts we have with each of our 38 members. These contracts, which extend to December 31, 2050, are substantially identical and obligate our members jointly and severally to pay all expenses associated with owning and operating our power supply business. As a cooperative, we operate on a not-for-profit basis and, accordingly, seek only to generate revenues sufficient to recover our cost of service and to generate margins sufficient to establish reasonable reserves and meet certain financial coverage requirements. While not significant, we also have short-term energy sales to non-members made through industry standard contracts. We do not have multiple operating segments. Pursuant to our contracts, we primarily provide two services, capacity and energy. Capacity and energy revenues are recognized by us upon transfer of control of promised services to our members and non-members in an amount that reflects the consideration we expect to receive in exchange for those services. Capacity and energy are distinct and we account for them as separate performance obligations. The obligations to provide capacity and energy are satisfied over time as the customer simultaneously receives and consumes the benefit of these services. Both performance obligations are provided directly by us and not through a third party. Each of our members is obligated to pay us for capacity and energy we furnish under its wholesale power contract in accordance with rates we establish. We review our rates periodically but are required to do so at least once every year. Revenues from our members are derived through a cost-plus rate structure which is set forth as a formula in the rate schedule to the wholesale power contracts. The formulary rate provides for the pass-through of our (i) fixed costs (net of any income from other sources) plus a targeted margin as capacity revenues and (ii) variable costs as energy revenues from our members. Power purchase and sale agreements between us and non-members obligate each non-member to pay us for capacity, if any, and energy furnished in accordance with the prices mutually agreed upon. Margins produced from non-member sales are included in our rate schedule formula and reduce revenue requirements from our members. The consideration we receive for providing capacity services is determined by our formulary rate on an annual basis. The components of the formulary rate associated with capacity costs include the annual budget of fixed costs, a targeted margin and income from other sources. Capacity revenues, therefore, vary to the extent these components vary. Fixed costs include items such as fixed operation and maintenance expenses, administrative and general expenses, depreciation and interest. Year to year, capacity revenue fluctuations are generally due to the recovery of fixed operation and maintenance expenses. Fixed costs also include certain costs, such as major maintenance costs, which will be recognized as expense in future periods. Recognition of revenues associated with these future expenses is deferred pursuant to Accounting Standards Codification (ASC) 980, Regulated Operations. The regulatory liabilities are amortized to revenue in accordance with the associated revenue deferral plan as the expenses are recognized. For information regarding regulatory accounting, see Note 1q. Capacity revenues are recognized by us for standing ready to deliver electricity to our customers. Our capacity revenues are based on the associated costs we expect to recover in a given year and are recognized and billed to our members in equal monthly installments over the course of the year regardless of whether our generation and purchased power resources are dispatched to produce electricity. Non-member capacity revenues, if any, are typically billed and recognized in equal monthly installments over the term of the contract. We have a power bill prepayment program pursuant to which our members may prepay future capacity costs and receive a discount. As this program provides us with financing, we adjust our capacity revenues by the amount of the discount, which is based on our avoided cost of borrowing. For additional information regarding our member prepayment program, see Note 1p. We satisfy our performance obligations to deliver energy as energy is delivered to the applicable meter points. We determine the standard selling price for energy we deliver to our members based upon the variable costs incurred to generate or purchase that energy. Fuel expense is the primary variable cost. Energy revenue recognized equals the actual variable expenses incurred in any given accounting period. Our member energy revenues fluctuate from period to period based on several factors, including fuel costs, weather and other seasonal factors, load requirements in our members’ service territories, variable operating costs, the availability of electric generation resources, our decisions of whether to dispatch our owned or purchased resources or member-owned resources over which we have dispatch rights, and by members’ decisions of whether to purchase a portion of their hourly energy requirements from our resources or from other suppliers. In 2020, 2019 and 2018, we provided approximately 57%, 58% and 57% of our members’ energy requirements, respectively. The standard selling price for our energy revenues from non-members is the price mutually agreed upon. We are required under our first mortgage indenture to produce a margins for interest ratio of at least 1.10 for each fiscal year. For 2020, 2019 and 2018, our board approved, and we achieved, a targeted margins for interest ratio of 1.14. Historically, our board of directors has approved adjustments to revenue requirements by year end such that revenue in excess of that required to meet the targeted margins for interest ratio is refunded to the members. Given that our capacity revenues are based upon budgeted expenditures and generally recognized and billed to our members in equal monthly installments over the course of the year, we may recognize capacity revenues that exceed our actual fixed costs and targeted margins in any given interim reporting period. At each interim reporting period we assess our projected revenue requirements through year end to determine whether a refund to our members of excess consideration is likely. If so, we reduce our capacity revenues and recognize a refund liability to our members. Refund liabilities, if any, are included in accounts payable on our consolidated balance sheets. As of December 31, 2020 and December 31, 2019, we recognized refund liabilities totaling $32,318,000 and $14,989,000, respectively. Based on our current agreements with non-members, we do not refund any consideration received from non-members. Sales to members were as follows: (dollars in thousands) 2020 2019 2018 Capacity revenues $ 971,071 $ 942,057 $ 927,419 Energy revenues 405,939 487,795 551,960 Total $ 1,377,010 $ 1,429,852 $ 1,479,379 The following table reflects members whose revenues accounted for 10% or more of our total operating revenues in 2020, 2019 or 2018: 2020 2019 2018 Jackson EMC 15.2 % 14.4 % 14.1 % Cobb EMC 13.2 % 13.8 % 13.9 % Receivables from contracts with our members at December 31, 2020 and December 31, 2019 were $135,462,000 and $142,946,000, respectively. Sales to non-members during years 2020, 2019 and 2018 were insignificant. Electric capacity and energy revenues are recognized by us without any obligation for returns, warranties or taxes collected. As our members are jointly and severally obligated to pay all expenses associated with owning and operating our power supply business and we perform an on-going assessment of the credit worthiness of non-members, we have not recorded an allowance for doubtful accounts associated with our receivables from members or non-members. We have a rate management program that allows us to expense and recover interest costs on a current basis that would otherwise be deferred or capitalized. The subscribing members of Vogtle Units No. 3 and No. 4 can elect to participate in this program on an annual basis. The Vogtle program allows for the recovery of financing costs associated with the construction of Vogtle Units No. 3 and No. 4 on a current basis. Under this program, amounts billed to participating members in 2020, 2019 and 2018 were $14,684,000, $14,943,000 and $12,229,000, respectively. The cumulative amount billed since inception of the program totaled $95,943,000. In 2018, we began an additional rate management program that allows us to recover future expense on a current basis from our members. In general, the program allows for additional collections over a five $15,435,000 respectively. Funds collected through this program are invested and held until applied to members’ bills. In conjunction with this program, we are applying regulated operations accounting to defer these revenues and related investment income on the funds collected. Amounts deferred under the program will be amortized to income when applied to members’ bills. The cumulative amount billed since inception of the program totaled $214,328,000. f. Receivables A substantial portion of our receivables are related to capacity and energy sales to our members. These receivables are recorded at the invoiced amount and do not bear interest. Our members are required through the wholesale power contracts to reimburse us for all costs, plus a margin requirement. Receivables from contracts with our members at December 31, 2020, 2019 and 2018 were $135,462,000, $142,946,000 and $122,888,000, respectively. Payment is typically received the following month in which capacity and energy are billed. Estimated energy charges are billed based on the amount of energy supplied during the month and are adjusted when actual costs are available, generally the following month. The remainder of our receivables is primarily related to transactions with affiliated companies and investment income. As a result of our historical experience, the short duration lifetime of our receivables and the short time horizon over which to consider expectations of future economic conditions, we have assessed that non-collection of the cost basis of our receivables is remote. During 2020, 2019 and 2018, no credit losses were recognized on any receivables that arose from contracts with members or non-members. g. Nuclear fuel cost The cost of nuclear fuel is amortized to fuel expense based on usage. The total nuclear fuel expense for 2020, 2019 and 2018 amounted to $75,968,000, $79,893,000, and $85,949,000, respectively. Contracts with the U.S. Department of Energy have been executed to provide for the permanent disposal of spent nuclear fuel produced at Plants Hatch and Vogtle. The Department of Energy failed to begin disposing of spent fuel in January 1998 as required by the contracts, and Georgia Power, as agent for the co-owners of the plants has pursued and continues to pursue legal remedies against the Department of Energy for breach of contract. Georgia Power filed claims against the U.S. government in 2014 (as amended) seeking damages for spent nuclear fuel storage costs at Plant Hatch and Plant Vogtle Units No. 1 and No. 2 covering the period from January 1, 2011 through December 31, 2014. On June 12, 2019, the U.S. Court of Federal Claims granted Georgia Power’s motion for summary judgement on damages not disputed by the U.S. Government and awarded the undisputed damages to Georgia Power. However, these undisputed damages are not collectable by Georgia Power and no amounts will be recognized in our financial statements until the court enters final judgement on the remaining damages. Georgia Power filed additional claims against the U.S. government in 2017 seeking damages for spent nuclear fuel storage costs at Plant Hatch and Plant Vogtle Units No. 1 and No. 2 covering the period from January 1, 2015 through December 31, 2017. On August 13, 2020, Georgia Power filed amended complaints in each of the lawsuits against the U.S. government in the Court of Federal Claims for damages from January 1, 2018 to December 31, 2019. Damages will continue to accumulate until the issue is resolved or storage is provided. No amounts were recognized in the consolidated financial statements as of December 31, 2020 or December 31, 2019 for these additional claims. The final outcome of these matters cannot be determined at this time. Both Plants Hatch and Vogtle have on-site dry spent storage facilities in operation. Facilities at both plants can be expanded to accommodate spent fuel through the expected life of each plant. h. Asset retirement obligations and other retirement costs Asset retirement obligations are legal obligations associated with the retirement of long-lived assets. These obligations represent the present value of the estimated costs for an asset's future retirement discounted using a credit-adjusted risk-free rate, and are recorded in the period in which the liability is incurred. The liabilities we have recognized primarily relate to the decommissioning of our nuclear facilities and coal ash ponds. In addition, we have retirement obligations related to gypsum cells, powder activated carbon cells, landfill sites and asbestos removal. Under the accounting provision for regulated operations, we record a regulatory asset or liability to reflect the difference in timing of recognition of the costs related to nuclear and coal ash related decommissioning for financial statement purposes and for ratemaking purposes. Periodically, we obtain revised cost studies associated with our nuclear and fossil plants' asset retirement obligations. Actual retirement costs may vary from these estimates. The estimated costs of nuclear and coal ash pond decommissioning are based on the most recent studies performed in 2018 and 2019, respectively. The following table reflects the details of the asset retirement obligations included in the consolidated balance sheets for the years 2020 and 2019. (dollars in thousands) Nuclear Coal Ash Pond Other Total Balance at December 31, 2019 $ 697,441 $ 329,264 $ 43,935 1,070,640 Liabilities settled — (4,656) (2,332) (6,988) Accretion 40,776 12,059 1,640 54,475 Deferred accretion — (853) — (853) Change in cash flow estimates — 10,775 7,934 18,709 Balance at December 31, 2020 $ 738,217 $ 346,589 $ 51,177 $ 1,135,983 (dollars in thousands) Nuclear Coal Ash Pond Other Total Balance at December 31, 2018 $ 658,956 $ 326,248 $ 32,359 $ 1,017,563 Liabilities settled — (3,380) (1,158) (4,538) Accretion 38,485 10,494 1,494 50,473 Deferred accretion — 1,860 — 1,860 Change in cash flow estimates — (5,958) 11,240 5,282 Balance at December 31, 2019 $ 697,441 $ 329,264 $ 43,935 $ 1,070,640 Asset Retirement Obligations Nuclear Decommissioning. Nuclear decommissioning cost estimates are based on site studies and assume prompt dismantlement and removal of both the radiated and non-radiated portions of the plant from service, as well as the management of spent fuel. We do not have a legal obligation to decommission non-radiated structures and, therefore, these costs are excluded from the related asset retirement obligation and the amounts in the table above. Actual decommissioning costs may vary from these estimates because of, but not limited to, changes in the assumed date of decommissioning, changes in regulatory requirements, changes in technology, and changes in costs of labor, materials and equipment. Our most recent assessment of the nuclear asset obligation, which occurred in 2018 resulted in an increase in the obligation for nuclear decommissioning. That increase in the cash flow estimates was primarily attributable to general inflation, labor costs, volume of low-level radioactive waste and spent fuel management, among other factors. Our portion of the estimated costs of decommissioning co-owned nuclear facilities are as follows: (dollars in thousands) 2018 site study Hatch Hatch Vogtle Vogtle Expected start date of decommissioning 2034 2038 2047 2049 Estimated costs based on site study in 2018 dollars: Radiated structures $ 209,000 $ 231,000 $ 188,000 $ 206,000 Spent fuel management 54,000 49,000 55,000 51,000 Non-radiated structures 14,000 19,000 23,000 29,000 Total estimated site study costs $ 277,000 $ 299,000 $ 266,000 $ 286,000 We have established funds to comply with the Nuclear Regulatory Commission regulations regarding the decommissioning of our nuclear plants. See Note 1i for information regarding the nuclear decommissioning funds. We apply the provision of regulated operations to nuclear decommissioning transactions such that collections and investment income (interest, dividends and realized gains and losses) of our nuclear decommissioning funds are compared to the associated decommissioning expenses with the difference deferred as regulatory asset or liability. As this difference is largely attributable to the timing of decommissioning fund earnings, the difference is recorded as an adjustment to investment income in our consolidated statements of revenues and expenses. Unrealized gains and losses of the decommissioning funds are recorded directly to the regulatory asset or liability for asset retirement obligations in accordance with our ratemaking treatment. Coal Combustion Residuals. Coal combustion residuals (CCR) are subject to Federal and State regulations. Our obligations associated with CCR are primarily for the closure of coal ash ponds. During 2020 and 2019, assessments of the coal ash pond asset retirement obligation resulted in a $10,775,000 increase and a $5,958,000 decrease in the obligation for coal ash decommissioning, respectively. Estimates are based on various assumptions including, but not limited to, closure and post-closure cost estimates, timing of expenditures, escalation factors, discount rates and methods for complying with the CCR regulations. Additional adjustments to the asset retirement obligations are expected periodically due to potential changes in estimates and assumptions. We have internally segregated the funds collected for coal ash pond and landfill decommissioning costs, including earnings thereon. As of December 31, 2020 and December 31, 2019 the fund balances were $120,536,000 and $93,184,000, respectively. We apply the provision of regulated operations to coal ash pond and landfill decommissioning transactions such that collections and investment income (interest, dividends and realized gains and losses) are compared to the associated decommissioning expenses with the difference deferred to or amortized from the regulatory asset. This difference is recorded to the associated expenses in our consolidated statements of revenues and expenses. Unrealized gains and losses of the associated decommissioning fund are recorded directly to the regulatory asset in accordance with our ratemaking treatment. Other Retirement Costs Accounting standards for asset retirement and environmental obligations do not apply to a retirement cost for which there is no legal obligation to retire the asset, and non-regulated entities are not allowed to accrue for such future retirement costs. We continue to recognize retirement costs for these other obligations in our depreciation rates under the accounting provisions for regulated operations. Accordingly, the accumulated retirement costs for other obligations are reflected as a regulatory liability in our balance sheets. For information regarding accumulated retirement costs for other obligations, see Note 1q. i. Nuclear decommissioning funds The Nuclear Regulatory Commission (NRC) requires all licensees operating commercial power reactors to establish a plan for providing, with reasonable assurance, funds for decommissioning. The NRC definition of decommissioning does not include all costs that may be associated with decommissioning, such as spent fuel management and non-radiated structures. We have established external trust funds to comply with the NRC's regulations. Upon approval by the NRC, any funding in the external trust in excess of their requirements may be used for other decommissioning costs. In 2020 and 2019, no additional amounts were contributed to the external trust funds. These funds are managed by unrelated third party investment managers with the discretion to buy, sell and invest pursuant to investment objectives and restrictions set forth in agreements entered into between us and the investment managers. We record the investment securities held in the nuclear decommissioning trust fund at fair value, as disclosed in Note 2. Because day-to-day investment decisions are made by third party investment managers, the ability to hold investments in unrealized loss positions is outside our control. In addition to the external trust funds, we maintain unrestricted investments internally designated for nuclear decommissioning. These internal funds are available to be utilized to fund the external trust funds, should additional funding be required, as well as other decommissioning costs outside the scope of the NRC funding regulations. The funds are included in long-term investments on our consolidated balance sheet. In both 2020 and 2019, we contributed $4,750,000 into the internal funds. The following table outlines the fair value of our nuclear decommissioning funds as of December 31, 2020 and December 31, 2019. The funds were invested in a diversified mix of approximately 64% equity and 36% fixed income securities in 2020 and 2019. 2020 External Trust Funds: (dollars in thousands) Cost Purchases Net Proceeds(1) Unrealized Gain(Loss) Fair Value 12/31/2020 Equity $ 212,585 $ 27,707 $ (16,444) $ 177,866 $ 401,714 Debt 174,645 536,147 (523,926) 11,100 197,966 Other (702) 14,756 (15,553) — (1,499) $ 386,528 $ 578,610 $ (555,923) $ 188,966 $ 598,181 (1) Also included in net proceeds are net realized gains or losses, interest income, dividends and fees of $22,686,000. 2020 Internal Funds: (dollars in thousands) Cost Purchases Net Unrealized Fair Value Equity $ 47,062 $ — $ 3,586 $ 33,665 $ 84,313 Debt 44,347 132,710 (126,590) 2,519 52,986 $ 91,409 $ 132,710 $ (123,004) $ 36,184 $ 137,299 (1) Also included in net proceeds are net realized gains or losses, interest income, dividends, contributions and fees of $9,705,000. 2019 External Trust Funds: (dollars in thousands) Cost Purchases Net Unrealized Fair Value Equity $ 207,313 $ 11,950 $ (6,678) $ 119,263 $ 331,848 Debt 166,023 361,844 (353,222) 5,548 180,193 Other 115 544 (1,361) — (702) $ 373,451 $ 374,338 $ (361,261) $ 124,811 $ 511,339 (1) Also included in net proceeds are net realized gains or losses, interest income, dividends and fees of $13,078,000. 2019 Internal Funds: (dollars in thousands) Cost Purchases Net Unrealized Fair Value Equity $ 44,295 $ — $ 2,767 $ 19,578 $ 66,640 Debt 38,382 140,997 (135,033) 1,161 45,507 $ 82,677 $ 140,997 $ (132,266) $ 20,739 $ 112,147 (1) Also included in net proceeds are net realized gains or losses, interest income, dividends, contributions and fees of $8,732,000. Realized and unrealized gains and losses of the nuclear decommissioning funds that would be recorded in earnings by a non-regulated entity are directly deducted from or added to the regulatory asset or liability for asset retirement obligations in accordance with our rate-making treatment. The nuclear decommissioning trust fund has produced an average annualized return of approximately 8.4% in the last ten years and 6.9% since inception in 1990. Based on current funding and cost study estimates, we expect the current balances and anticipated investment earnings of our decommissioning fund assets to be sufficient to meet all of our future nuclear decommissioning costs. Notwithstanding the above assumption, our management believes that increases in cost estimates of decommissioning can be recovered in future rates. j. Depreciation Depreciation is computed on additions when they are placed in service using the composite straight-line method. We use standard depreciation rates as well as site specific rates determined through depreciation studies as approved by the Rural Utilities Service. The depreciation rates for steam and nuclear production in the table below reflect revised rates from depreciation rate studies completed in 2015. Site specific depreciation studies are performed every five years. Annual weighted average depreciation rates in effect in 2020, 2019, and 2018 were as follows: Range of 2020 2019 2018 Steam production 49-65 2.58 % 2.61 % 2.57 % Nuclear production 37-60 1.93 % 1.94 % 1.92 % Hydro production 50 2.00 % 2.00 % 2.00 % Other production 25-35 2.61 % 2.61 % 2.61 % Transmission 36 2.75 % 2.75 % 2.75 % General 3-50 2.00-33.33% 2.00-33.33% 2.00-33.33% * Calculated based on the composite depreciation rates in effect for 2020. Depreciation expense for the years 2020, 2019 and 2018 was $242,822,000, $237,447,000, and $227,213,000, respectively. k. Electric plant Electric plant is stated at original cost, which is the cost of the plant when first dedicated to public service, including acquisition adjustments, if any, plus the cost of any subsequent additions. Cost includes an allowance for the cost of equity and debt funds used during construction and allocable overheads. For the years 2020, 2019 and 2018, the allowance for funds used during construction rates were 4.00%, 4.30% and 4.25%, respectively. Replacements and renewals of items considered to be units of property, the lowest level of property for which we capitalize, are charged to the plant accounts. At the time properties are disposed of, the original cost is charged to the accumulated provision for depreciation. Cost of removal, less salvage, is charged to a regulatory liability, accumulated retirement costs for other assets. Maintenance and repairs of property and replacements and renewals of items determined to be less than units of property are charged to expense, including certain major maintenance costs at our natural gas-fired plants. l. Cash and cash equivalents We consider all temporary cash investments purchased with an original maturity of three months or less to be cash equivalents. Temporary cash investments with maturities at the time of purchase of more than three months are classified as short-term investments. m. Restricted investments Restricted investments consist of funds on deposit with the Rural Utilities Service in the Cushion of Credit Account that are held by the U.S. Treasury, acting through the Federal Financing Bank. We can only utilize these investments for future Rural Utilities Service-guaranteed Federal Financing Bank debt service payments. Through September 30, 2020 funds earned interest at a rate of 5% per annum. Beginning October 1, 2020, deposits earn interest at 4% per annum and beginning October 1, 2021, the rates will be set at the 1-year floating treasury rate. The program no longer allows additional funds to be deposited into the account. At December 31, 2020 and 2019, we had restricted investments totaling $487,587,000 and $533,590,000, respectively, of which $306,601,000 and $461,757,000, respectively, were classified as long-term. n. Inventories We maintain inventories of fossil fuel and spare parts, including materials and supplies for our generation plants. These inventories are stated at weighted average cost. The fossil fuel inventories primarily include the direct cost of coal and related transportation charges. The cost of fossil fuel inventories is carried at weighted average cost and is charged to fuel expense as consumed. The spare parts inventories primarily include the direct cost of generating plant spare parts. The spare parts inventory is carried at weighted average cost and the parts are charged to expense or capitalized, as appropriate when installed. At December 31, 2020 and December 31, 2019, fossil fuels |
Fair Value
Fair Value | 12 Months Ended |
Dec. 31, 2020 | |
Fair Value Disclosures [Abstract] | |
Fair Value | Fair Value: Authoritative guidance regarding fair value measurements for financial and non-financial assets and liabilities defines fair value, establishes a framework for measuring fair value in accordance with generally accepted accounting principles, and expands disclosures about fair value measurements. The guidance establishes a three-tier fair value hierarchy which prioritizes the inputs used in measuring fair value as follows: • Level 1. Quoted prices from active markets for identical assets or liabilities as of the reporting date. Active markets are those in which transactions for the asset or liability occur in sufficient frequency and volume to provide pricing information on an ongoing basis. Quoted prices in active markets provide the most reliable evidence of fair value and are used to measure fair value whenever available. Level 1 primarily consists of financial instruments that are exchange-traded. • Level 2. Pricing inputs other than quoted prices in active markets included in Level 1, which are either directly or indirectly observable as of the reporting date. Level 2 includes financial instruments that are valued using models or other valuation methodologies. These models are primarily industry-standard models that consider various assumptions, including quoted forward prices for commodities, time value, volatility factors, and current market and contractual prices for the underlying instruments, as well as other relevant economic measures. Level 2 primarily consists of financial instruments that are non-exchange-traded but have significant observable inputs. • Level 3. Pricing inputs that include significant inputs which are generally less observable from objective sources. These inputs may include internally developed methodologies that result in management's best estimate of fair value. Level 3 financial instruments are those whose fair value is based on significant unobservable inputs. Assets and liabilities measured at fair value are based on one or more of the following three valuation techniques: (1) Market approach. The market approach uses prices and other relevant information generated by market transactions involving identical or comparable assets or liabilities (including a business) and deriving fair value based on these inputs. (2) Income approach. The income approach uses valuation techniques to convert future amounts (for example, cash flows or earnings) to a single present amount (discounted). The measurement is based on the value indicated by current market expectations about those future amounts. (3) Cost approach. The cost approach is based on the amount that currently would be required to replace the service capacity of an asset (often referred to as current replacement cost). This approach assumes that the fair value would not exceed what it would cost a market participant to acquire or construct a substitute asset or comparable utility adjusted for obsolescence. Fair Value Measurements at Reporting Date Using December 31, 2020 Quoted Prices in Significant Other Significant (dollars in thousands) Nuclear decommissioning trust funds: Domestic equity $ 198,325 $ 198,325 $ — $ — International equity trust $ 120,645 — 120,645 — Corporate bonds and debt $ 98,129 — 97,788 341 US Treasury securities $ 46,963 46,963 — — Mortgage backed securities $ 45,039 — 45,039 — Domestic mutual funds $ 70,813 70,813 — — Municipal bonds $ 1,362 — 1,362 — Federal agency securities $ 6,054 — 6,054 — Other $ 10,851 7,720 3,131 — Long-term investments: International equity trust $ 31,378 — 31,378 — Corporate bonds and debt $ 29,870 — 29,661 209 US Treasury securities $ 7,437 7,437 — — Mortgage backed securities $ 11,432 — 11,432 — Domestic mutual funds $ 224,536 224,536 — — Federal agency securities $ 537 — 537 — Treasury STRIPS $ 209,165 — 209,165 — Other $ 3,710 3,710 — — Natural gas swaps $ 10,248 — 10,248 — Fair Value Measurements at Reporting Date Using December 31, 2019 Quoted Prices in Significant Other Significant (dollars in thousands) Nuclear decommissioning trust funds: Domestic equity $ 179,346 $ 179,346 $ — $ — International equity trust $ 96,204 — 96,204 — Corporate bonds and debt $ 63,849 — 63,849 — US Treasury securities $ 45,522 45,522 — — Mortgage backed securities $ 62,400 — 62,400 — Domestic mutual funds $ 55,522 55,522 — — Municipal bonds $ 1,189 — 1,189 — Federal agency securities $ 2,586 — 2,586 — Other $ 4,721 4,450 271 — Long-term investments: International equity trust $ 23,161 — 23,161 — Corporate bonds and debt $ 20,395 — 20,395 — US Treasury securities $ 9,257 9,257 — — Mortgage backed securities $ 12,867 — 12,867 — Domestic mutual funds $ 126,380 126,380 — — Federal agency securities $ 1,082 — 1,082 — Treasury STRIPS $ 59,816 — 59,816 — Other $ 1,906 1,906 — — Natural gas swaps $ 32,256 — 32,256 — The Level 2 investments above in corporate bonds and debt, federal agency mortgage backed securities, and mortgage backed securities may not be exchange traded. The fair value measurements for these investments are based on a market approach, including the use of observable inputs. Common inputs include reported trades and broker/dealer bid/ask prices. The fair value of the Level 2 investments above in international equity trust are calculated based on the net asset value per share of the fund. There are no unfunded commitments for the international equity trust and redemption may occur daily with a 3-day redemption notice period. The Level 3 investments above in corporate bonds and debt consist of investments in bank loans which are not exchange traded. Although these securities may be liquid and priced daily, their inputs are not observable. The estimated fair values of our long-term debt, including current maturities at December 31, 2020 and 2019 were as follows: 2020 2019 (in thousands) Carrying Fair Carrying Fair Long-term debt $ 10,619,826 $ 13,161,146 $ 9,726,428 $ 11,180,658 The estimated fair value of long-term debt is classified as Level 2 and is based on observed or quoted market prices for the same or similar issues, or based on current rates offered to us for debt of similar maturities. The primary sources of our long-term debt consist of first mortgage bonds, pollution control revenue bonds and long-term debt issued by the Federal Financing Bank that is guaranteed by the Rural Utilities Service or the U.S. Department of Energy. The valuations for the first mortgage bonds and the pollution control revenue bonds were obtained from a third party data reporting service, and are based on secondary market trading of our debt. Valuations for debt issued by the Federal Financing Bank are based on U.S. Treasury rates as of December 31, 2020 plus an applicable spread, which reflects our borrowing rate for new loans of this type from the Federal Financing Bank. |
Derivative instruments
Derivative instruments | 12 Months Ended |
Dec. 31, 2020 | |
Derivative Instruments and Hedging Activities Disclosure [Abstract] | |
Derivative instruments | Derivative instruments: We use commodity trading derivatives to manage our exposure to fluctuation in the market price of natural gas. Our risk management and compliance committee provides general oversight over all derivative activities. We do not apply hedge accounting to derivative transactions, but instead apply regulated operations accounting. Consistent with our rate-making, unrealized gains or losses on our natural gas swaps are reflected as regulatory assets or liabilities, as appropriate. Realized gains and losses on natural gas swaps are included in fuel expense within our consolidated statements of revenues and expenses and, therefore, net margins within our consolidated statements of cash flows. We are exposed to credit risk as a result of entering into these hedging arrangements. Credit risk is the potential loss resulting from a counterparty's nonperformance under an agreement. We have established policies and procedures to manage credit risk through counterparty analysis, exposure calculation and monitoring, exposure limits, collateralization and certain other contractual provisions. It is possible that volatility in commodity prices could cause us to have credit risk exposures with one or more counterparties. If such counterparties fail to perform their obligations, we could suffer a financial loss. However, as of December 31, 2020 all of the counterparties with transaction amounts outstanding under our hedging programs are rated investment grade by the major rating agencies or have provided a guaranty from one of their affiliates that is rated investment grade. We have entered into International Swaps and Derivatives Association agreements with our natural gas hedge counterparties that mitigate credit exposure by creating contractual rights relating to creditworthiness, collateral, termination and netting (which, in certain cases, allows us to use the net value of affected transactions with the same counterparty in the event of default by the counterparty or early termination of the agreement). Additionally, we have implemented procedures to monitor the creditworthiness of our counterparties and to evaluate nonperformance in valuing counterparty positions. We have contracted with a third party to assist in monitoring certain of our counterparties' credit standing and condition. Net liability positions are generally not adjusted as we use derivative transactions as hedges and have the ability and intent to perform under each of our contracts. In the instance of net asset positions, we consider general market conditions and the observable financial health and outlook of specific counterparties, forward looking data such as credit default swaps, when available, and historical default probabilities from credit rating agencies in evaluating the potential impact of nonperformance risk to derivative positions. The contractual agreements contain provisions that could require us or the counterparty to post collateral or credit support. The amount of collateral or credit support that could be required is calculated as the difference between the aggregate fair value of the hedges and pre-established credit thresholds. The credit thresholds are contingent upon each party's credit ratings from the major credit rating agencies. The collateral and credit support requirements vary by contract and by counterparty. Under the natural gas swap arrangements, we pay the counterparty a fixed price for specified natural gas quantities and receive a payment for such quantities based on a market price index. These payment obligations are netted, such that if the market price index is lower than the fixed price, we will make a net payment, and if the market price index is higher than the fixed price, we will receive a net payment. At December 31, 2020 and 2019, the estimated fair value of our natural gas contracts was a net liability of $10,248,000 and $32,256,000, respectively. As of December 31, 2020 and 2019, neither we nor any counterparties were required to post credit support or collateral under the natural gas swap agreements. If the credit-risk-related contingent features underlying these agreements were triggered on December 31, 2020 due to our credit rating being downgraded below investment grade, we would have been required to post letters of credit of approximately $10,248,000 with our counterparties. The following table reflects the volume activity of our natural gas derivatives as of December 31, 2020 that is expected to settle or mature each year: Year Natural Gas (in millions) 2021 27.5 2022 23.7 2023 18.7 2024 17.5 2025 13.4 Total 100.8 The table below reflects the fair value of derivative instruments and their effect on our consolidated balance sheets at December 31, 2020 and 2019. Consolidated Balance Sheet Fair Value 2020 2019 (dollars in thousands) Assets Natural gas swaps Other current assets $ 222 $ — Liabilities Natural gas swaps Other current liabilities $ 2,305 $ 12,898 Natural gas swaps Other deferred credits $ 8,165 $ 19,358 The following table presents the realized gains and (losses) on derivative instruments recognized in margin for the years ended December 31, 2020, 2019 and 2018. Consolidated 2020 2019 2018 (dollars in thousands) Natural Gas Swaps Fuel $ 830 $ 224 $ 6,088 Natural Gas Swaps Fuel (21,179) (9,308) (956) Total $ (20,349) $ (9,084) $ 5,132 The following table presents the unrealized (gains) and losses on derivative instruments deferred on the consolidated balance sheet at December 31, 2020 and 2019. Consolidated Balance 2020 2019 (dollars in thousands) Natural Gas Swaps Regulatory asset $ 10,248 $ 32,256 Total $ 10,248 $ 32,256 |
Investments
Investments | 12 Months Ended |
Dec. 31, 2020 | |
Schedule of Investments [Abstract] | |
Investments | Investments: Investments in debt and equity securities Investment securities we hold are recorded at fair value in the accompanying consolidated balance sheets. We apply regulated operations accounting to the unrealized gains and losses of all investment securities. All realized and unrealized gains and losses are determined using the specific identification method. The following tables summarize debt and equity securities at December 31, 2020 and 2019. (dollars in thousands) Gross Unrealized 2020 Cost Gains Losses Fair Value Equity $ 262,564 $ 219,658 $ (8,127) $ 474,095 Debt 613,271 18,090 (641) 630,720 Other 11,431 — — 11,431 Total $ 887,266 $ 237,748 $ (8,768) $ 1,116,246 (dollars in thousands) Gross Unrealized 2019 Cost Gains Losses Fair Value Equity $ 258,870 $ 144,832 $ (5,990) $ 397,712 Debt 354,535 8,474 (874) 362,135 Other 6,356 — — 6,356 Total $ 619,761 $ 153,306 $ (6,864) $ 766,203 The contractual maturities of debt securities, which are included in the estimated fair value table above, at December 31, 2020 and 2019 are as follows: (dollars in thousands) 2020 2019 Cost Fair Value Cost Fair Value Due within one year $ 163,890 $ 164,635 $ 81,637 $ 81,914 Due after one year through five years 242,958 247,857 47,212 48,188 Due after five years through ten years 68,659 73,479 51,892 54,184 Due after ten years 137,764 144,749 173,794 177,849 Total $ 613,271 $ 630,720 $ 354,535 $ 362,135 The following table summarizes the realized gains and losses and proceeds from sales of securities for the years ended December 31, 2020, 2019 and 2018: (dollars in thousands) 2020 2019 2018 Gross realized gains $ 36,647 $ 18,076 $ 14,268 Gross realized losses (16,868) (12,018) (19,139) Proceeds from sales 756,513 544,043 626,612 Investment in associated companies Investments in associated companies were as follows at December 31, 2020 and 2019: (dollars in thousands) 2020 2019 National Rural Utilities Cooperative Finance Corporation (CFC) $ 24,080 $ 24,065 CT Parts, LLC 6,554 7,175 Georgia Transmission Corporation 33,943 32,106 Georgia System Operations Corporation 7,500 7,000 Other 2,767 2,972 Total $ 74,844 $ 73,318 The CFC investments consist of capital term certificates required in connection with our membership in CFC and a voluntary investment in CFC member capital securities. Accordingly, there is no market for these investments and they are valued at cost. The investment in Georgia Transmission represents capital credits valued at cost. The investment in Georgia System Operations represents loan advances. Repayments of these advances are due by December 2024. CT Parts, LLC is an affiliated organization formed by us and Smarr EMC for the purpose of purchasing and maintaining spare parts inventory and for the administration of contracted services for combustion turbine generation facilities. Such investment is recorded at cost. Rocky Mountain transactions In December 1996 and January 1997, we entered into six long-term lease transactions relating to our 74.61% undivided interest in Rocky Mountain. In each transaction, we leased a portion of our undivided interest in Rocky Mountain to six separate owner trusts for the benefit of three investors, referred to as owner participants, for a term equal to 120% of the estimated useful life of Rocky Mountain. Immediately thereafter, the owner trusts leased their undivided interests in Rocky Mountain to our wholly owned subsidiary, Rocky Mountain Leasing Corporation, or RMLC, for a term of 30 years under six separate leases. RMLC then subleased the undivided interests back to us under six separate leases for an identical term. In 2012, we terminated five of the six lease transactions prior to the end of their lease terms. The remaining lease in place represented approximately 10% of the original lease transactions. Pursuant to a payment undertaking agreement, we have a guarantee for the annual basic rent payments due under the remaining lease. The fair value amount relating to the guarantee of basic rent payment is immaterial to us principally due to the high credit rating of the payment undertaker, Rabobank Nederland. The basic rental payments remaining through the end of the lease, which expires in 2027, are approximately $30,892,000. At the end of the term of the remaining facility lease, we have the option to cause RMLC to purchase the owner trust's undivided interest in Rocky Mountain at a fixed purchase option price of approximately $112,000,000. The payment undertaking agreement, along with the equity funding agreement with AIG Matched Funding Corp., would fund approximately $74,000,000 and $37,928,000 of this amount, respectively, and these amounts would be paid to the owner trust over five installments in 2027. If we do not elect to cause RMLC to purchase the owner trust's undivided interest in Rocky Mountain, Georgia Power has an option to purchase the undivided interest. If neither we nor Georgia Power exercise our purchase option, and we return (through RMLC) the undivided interest in Rocky Mountain to the owner trust, the owner trust has several options it can elect, including: • causing RMLC and us to renew the related facility lease and facility sublease for up to an additional 16 years and provide collateral satisfactory to the owner trust, • leasing its undivided interest to a third party under a replacement lease, or • retaining the undivided interest for its own benefit. Under the first two of these options we must arrange new financing for the outstanding amount of the loan used to finance the owner trust's upfront rental payment made to us when the lease closed on December 31, 1996. At the end of the lease term, the amount of the outstanding loan is anticipated to be approximately $74,000,000. If new financing cannot be arranged, the owner trust can ultimately cause us to purchase 49%, in the case of the first option above, or all, in the case of the second option above, of the loan certificate or cause RMLC to exercise its purchase option or RMLC to renew the facility lease and facility sublease, respectively. The assets of RMLC are not available to pay our creditors. |
Income taxes
Income taxes | 12 Months Ended |
Dec. 31, 2020 | |
Income Tax Disclosure [Abstract] | |
Income taxes | Income taxes: While we are a not-for-profit membership corporation formed under the laws of the state of Georgia, we are subject to federal and state income taxation. As a taxable cooperative, we are allowed to deduct patronage dividends that we allocate to our members for purposes of calculating our taxable income. We annually allocate income and deductions between patronage and non-patronage activities and substantially all of our income is from patronage-sourced activities, resulting in no current period income tax expense or current or deferred income tax liability. Although we believe that treatment of non-member sales as patronage-sourced income is appropriate, this treatment has not been examined by the Internal Revenue Service. If this treatment was not sustained, we believe that the amount of taxes on such non-member sales, after allocating related expenses against the revenues from such sales, would not have a material adverse effect on our financial condition or results of operations and cash flows. We account for income taxes pursuant to the authoritative guidance for accounting for income taxes, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements or tax returns. The difference between the statutory federal income tax rate on income before income taxes and our effective income tax rate is summarized as follows: 2020 2019 2018 Statutory federal income tax rate 21.0 % 21.0 % 21.0 % Patronage exclusion (21.0) % (21.0) % (20.8) % AMT credit monetization 0.0 % 0.0 % 0.0 % Other 0.0 % 0.0 % (0.2) % Effective income tax rate 0.0 % 0.0 % 0.0 % The components of our net deferred tax assets and liabilities as of December 31, 2020 and 2019 were as follows: (dollars in thousands) 2020 2019 Deferred tax assets Net operating losses $ — $ 1,123 Tax credits (alternative minimum tax and other) — — Accounting for Rocky Mountain transactions 232,169 231,844 Advance payments 112,394 74,482 Other assets 91,938 88,821 Deferred tax assets 436,501 396,270 Less: Valuation allowance — (1,123) Net deferred tax assets $ 436,501 $ 395,147 Deferred tax liabilities Depreciation $ 254,047 $ 258,724 Accounting for Rocky Mountain transactions 119,773 118,021 Other liabilities 63,797 68,035 Deferred tax liabilities 437,617 444,780 Net deferred tax assets/(liabilities) (1,116) (49,633) Less: Patronage exclusion 1,116 49,633 Net deferred taxes $ — $ — Federal tax net operating loss carryforwards of $4,362,000 expired in the current year. The authoritative guidance for income taxes addresses the determination of whether tax benefits claimed or expected to be claimed on a tax return should be recorded in the financial statements. We may recognize the tax benefit from an uncertain tax position only if it is more likely than not that the tax position will be sustained on examination by the taxing authorities, based on the technical merits of the position. The tax benefits recognized in the financial statements from such a position should be measured based on the largest benefit that has a greater than fifty percent likelihood of being realized upon ultimate settlement. We file a U.S. federal consolidated income tax return. The U.S. federal statute of limitations remains open for the year 2017 and forward. State jurisdictions have statutes of limitations generally ranging from three to five years from the filing of an income tax return. The state impact of any federal changes remains subject to examination by various states for a period of up to one year after formal notification to the states. Years still open to examination by tax authorities in major state jurisdictions include 2017 and forward. We have no liabilities recorded for uncertain tax positions. |
Leases
Leases | 12 Months Ended |
Dec. 31, 2020 | |
Leases [Abstract] | |
Leases | Leases: As a lessee, we have a relatively small portfolio of leases with the most significant being our 60% undivided interest in Scherer Unit No. 2 and railcar leases for the transportation of coal. We also have various other leases of minimal value. We classify our four Scherer Unit No. 2 leases as finance leases and our railcar leases as operating leases. We have made an accounting policy election not to recognize right-of-use assets and lease liabilities that arise from short-term leases, leases having an initial term of 12 months or less, for any class of underlying asset. We recognize lease expense for short-term leases on a straight-line basis over the lease term. Lease expense recognized for our short-term leases during 2020 and 2019 was insignificant. Finance Leases Three of our Scherer Unit No. 2 finance leases have lease terms through December 31, 2027, and one lease extends through June 30, 2031. At the end of the leases, we can elect at our sole discretion to: • Renew the leases for a period of not less than one year and not more than five years at fair market value, • Purchase the undivided interest at fair market value, or • Redeliver the undivided interest to the lessors. For rate-making purposes, we include the actual lease payments for our finance leases in our cost of service. The difference between lease payments and the aggregate of the amortization on the right-of-use asset and the interest on the finance lease obligation is recognized as a regulatory asset. Finance lease amortization is recorded in depreciation and amortization expense. Operating Leases Our railcar operating leases have terms that extend through March 16, 2024. At the end of the railcar operating leases, we can renew at terms mutually agreeable by us and the lessors, purchase the assets or return the assets to the lessors. We have an additional operating lease that has a term that extends through February 2042 with one renewal option for a 20-year term. The exercise of renewal options for our finance and operating leases is at our sole discretion. As all of our operating leases do not provide an implicit rate, we used our incremental borrowing rate based on the information available at the time new lease agreements are entered into or reassessed to determine the present value of lease payments. For lease agreements entered into or reassessed after the adoption of the new leases standard, we combine lease and nonlease components. Classification 2020 2019 (dollars in thousands) Right-of-Use Assets - Finance leases Right-of-use assets $ 302,732 $ 302,732 Less: Accumulated provision for depreciation (262,774) (257,504) Total finance lease assets $ 39,958 $ 45,228 Lease liabilities - Finance leases Obligations under finance leases $ 68,876 $ 75,649 Long-term debt and finance leases due within one year 6,773 6,081 Total finance lease liabilities $ 75,649 $ 81,730 Classification 2020 2019 (dollars in thousands) Right-of-Use Assets - Operating leases Electric plant in service $ 3,283 $ 3,237 Total operating lease assets $ 3,283 $ 3,237 Lease liabilities - Operating leases Capitalization - Other $ 2,388 $ 2,293 Other current liabilities 990 1,252 Total operating lease liabilities $ 3,378 $ 3,545 2020 2019 (dollars in thousands) Lease Cost Classification Finance lease cost: Amortization of leased assets Depreciation and amortization $ 5,376 $ 4,756 Interest on lease liabilities Interest expense $ 8,868 $ 9,488 Operating lease cost Inventory(1) & production expense $ 1,305 $ 3,179 Total lease cost $ 15,549 $ 17,423 (1) The majority of our operating lease costs relate to our railcar leases and such costs are added to the cost of our fossil-fuel inventories and are recognized in fuel expense as the inventories are consumed. December 31, 2020 December 31, 2019 Lease Term and Discount Rate Weighted-average remaining lease term (in years): Finance leases 7.86 8.84 Operating leases 7.27 7.39 Weighted-average discount rate: Finance leases 11.05 % 11.05 % Operating leases 4.63 % 5.12 % 2020 2019 (dollars in thousands) Other Information: Cash paid for amounts included in the measurement of lease liabilities Operating cash flows from finance leases $ 8,868 $ 9,488 Operating cash flows from operating leases $ 1,540 $ 3,710 Financing cash flows from finance leases $ 6,082 $ 5,461 Right-of-use assets obtained in exchange for new operating lease liabilities $ 1,227 $ 6,983 Maturity analysis of our finance and operating lease liabilities as of December 31, 2020 is as follows: (dollars in thousands) Year Ending December 31, Finance Leases Operating Leases Total 2021 $ 14,949 $ 1,119 $ 16,068 2022 14,949 929 15,878 2023 14,949 708 15,657 2024 14,949 234 15,183 2025 14,949 72 15,021 Thereafter 40,583 1,012 41,595 Total lease payments $ 115,328 $ 4,074 $ 119,402 Less: imputed interest (39,679) (696) (40,375) Present value of lease liabilities $ 75,649 $ 3,378 $ 79,027 As a lessor, we primarily lease office space to several tenants within our headquarters building. Several of these tenants are related parties. We account for all of these lease agreements as operating leases. Lease income recognized during 2020 and 2019 was as follows: 2020 2019 Lease income $ 6,171 $ 6,071 |
Debt
Debt | 12 Months Ended |
Dec. 31, 2020 | |
Debt Disclosure [Abstract] | |
Debt | Debt: Long-term debt consists of first mortgage notes payable to the United States of America acting through the Federal Financing Bank (FFB) and guaranteed by the Rural Utilities Service or the U.S. Department of Energy, first mortgage bonds payable (FMBs) and first mortgage notes issued in conjunction with the sale by public authorities of pollution control revenue bonds (PCBs). Substantially all of our owned tangible and certain of our intangible assets are pledged under our first mortgage indenture as collateral for the Federal Financing Bank notes, the first mortgage bonds, and the first mortgage notes issued in conjunction with the sale of pollution control revenue bonds. Maturities for long-term debt and finance lease obligations through 2025 are as follows: (dollars in thousands) 2021 2022 2023 2024 2025 FFB $ 200,867 $ 275,553 $ 247,601 $ 222,273 $ 229,168 FMBs 1,010 1,010 1,010 63,510 62,500 PCBs (1) — — 122,620 245,605 — $ 201,877 $ 276,563 $ 371,231 $ 531,388 $ 291,668 Finance Leases 6,772 7,541 8,398 9,351 10,413 Total $ 208,649 $ 284,104 $ 379,629 $ 540,739 $ 302,081 (1) In addition to regularly scheduled principal payments included are amounts that would be due at the later of (i) maturity date of the credit support facilities backing the Series 2009 and Series 2010 pollution control bonds, or at the mandatory redemption date of the Series 2017A and Series 2017B pollution control bonds or (ii) at the maturity of an alternative back-up credit facility we currently have available to refinance draws on the credit facilities or provide alternate credit support for these bonds. We currently maintain a $1.21 billion syndicated bank credit facility with a maturity date of December 2024 which backs the Series 2010 pollution control bonds and would be available as an alternative back-up credit facility for the Series 2009 pollution control bonds noted above. As such, December 2024 is the designated maturity date for the Series 2009 and Series 2010 pollution control bonds totaling $245.6 million. The Series 2017 bonds totaling $122.6 million have a mandatory redemption in 2023 if the bonds are not remarketed before then, and as such, October 2023 is the designated maturity date for the Series 2017 bonds. The nominal maturities of the Series 2017 pollution control bonds range from 2040 to 2045. The weighted average interest rate on our long-term debt at December 31, 2020 and 2019 was 3.73% and 3.96%, respectively. Long-term debt outstanding and the associated unamortized debt issuance costs and debt discounts at December 31, 2020 and December 31, 2019 are as follows: 2020 2019 Principal Unamortized Debt Principal Unamortized Debt (dollars in thousands) FFB $ 5,985,015 $ 57,971 $ 5,540,215 $ 60,356 FMBs 3,654,041 49,134 3,205,052 39,793 PCRBs 980,770 12,460 980,770 11,073 CFC — — 391 — $ 10,619,826 $ 119,565 $ 9,726,428 $ 111,222 We use the effective interest rate method to amortize debt issuance costs and debt discounts as well as the straight-line method when the results approximate those of the effective interest rate method. Unamortized debt issuance costs and debt discounts are being amortized to expense over the life of the respective debt issues. a) Department of Energy Loan Guarantee: Pursuant to the loan guarantee program established under Title XVII of the Energy Policy Act of 2005, we and the U.S. Department of Energy, acting by and through the Secretary of Energy, entered into a Loan Guarantee Agreement on February 20, 2014 pursuant to which the Department of Energy agreed to guarantee our obligations under a Note Purchase Agreement, dated as of February 20, 2014 (the Original Note Purchase Agreement), among us, the Federal Financing Bank and the Department of Energy and two future advance promissory notes, each dated February 20, 2014, made by us to the Federal Financing Bank in the aggregate amount of $3,057,069,461 (the Original FFB Notes and together with the Original Note Purchase Agreement, the Original FFB Documents). On March 22, 2019, we and the Department of Energy entered into an Amended and Restated Loan Guarantee Agreement (as amended, the Loan Guarantee Agreement) which increased the aggregate amount guaranteed by the Department of Energy to $4,676,749,167. We also entered into a Note Purchase Agreement dated as of March 22, 2019 (the Additional Note Purchase Agreement), among us, the Federal Financing Bank and the Department of Energy and a future advance promissory note, dated March 22, 2019, made by us to the Federal Financing Bank in the amount of $1,619,679,706 (the Additional FFB Note and together with the Additional Note Purchase Agreement, the Additional FFB Documents). Together, the Original FFB Documents and Additional FFB Documents provide for a multi-advance term loan facility (the Facility) under which we may make long-term loan borrowings through the Federal Financing Bank. Proceeds of advances made under the Facility are used to reimburse us for a portion of certain costs of construction relating to Vogtle Units No. 3 and No. 4 that are eligible for financing under the Title XVII loan guarantee program (Eligible Project Costs). Borrowings under the Original FFB Notes could not exceed $3,057,069,461, of which $335,471,604 was designated for capitalized interest. We have advanced all amounts available under the Original FFB Notes. We were unable to advance $43,721,079 of the amount designated for capitalized interest under the Original FFB Notes due to the timing of borrowing and lower than expected interest rates. Borrowings under the Additional FFB Note may not exceed (i) $1,619,679,706 or (ii) an amount that, when aggregated with borrowings under the Original FFB Notes, equals 70% of Eligible Project Costs less the $1,104,000,000 guarantee payment we received from Toshiba Corporation in late 2017. At December 31, 2020, borrowings under the Additional FFB Note totaled $620,000,000. At December 31, 2020, aggregate Department of Energy-guaranteed borrowings, including capitalized interest, totaled $3,633,348,382. Under the Loan Guarantee Agreement, we are obligated to reimburse the Department of Energy in the event it is required to make any payments to the Federal Financing Bank under its guarantee. Our payment obligations to the Federal Financing Bank under the FFB Notes and reimbursement obligations to the Department of Energy under its guarantee, but not our covenants to the Department of Energy under the Loan Guarantee Agreement, are secured equally and ratably with all of our other obligations issued under our first mortgage indenture. The final maturity date for each advance is February 20, 2044. Interest is payable quarterly in arrears and principal payments on all advances under the FFB Notes began on February 20, 2020. As of December 31, 2020, we have repaid $79,100,000 of principal on the FFB Notes. Interest rates on advances during the applicable interest rate periods will equal the current average yield on U.S. Treasuries of comparable maturity at the beginning of the interest rate period, plus a spread equal to 0.375%. Advances under the Additional FFB Note may be requested on a quarterly basis through November 30, 2023, one year beyond the current anticipated commercial operation date of Vogtle Unit No. 4. Future advances under the Facility are subject to satisfaction of customary conditions, as well as (i) certification of compliance with the requirements of the Title XVII loan guarantee program, (ii) accuracy of project-related representations and warranties, (iii) delivery of updated project-related information, (iv) no Project Adverse Event (as described in Note 8) having occurred or, if a Project Adverse Event has occurred, that Co-owners (as described in Note 8) representing at least 90% of the ownership interests have voted to continue construction, have not deferred construction and we have provided the Department of Energy with certain additional information, (v) certification regarding Georgia Power's compliance with certain obligations relating to the Cargo Preference Act, as amended, (vi) evidence of compliance with the applicable wage requirements of the Davis-Bacon Act, as amended, (vii) certification from the Department of Energy's consulting engineer that proceeds of the advance are used to reimburse Eligible Project Costs and (viii) if either the Services Agreement or the Bechtel Agreement (each, as described in Note 8) are terminated, or rejected in bankruptcy proceedings, the Department of Energy has approved the replacement agreement. We may voluntarily prepay outstanding borrowings under the Facility. Under the FFB Documents, any prepayment will be subject to a make-whole premium or discount, as applicable. Any amounts prepaid may not be re-borrowed. Under the Loan Guarantee Agreement, we are subject to customary borrower affirmative and negative covenants and events of default. In addition, we are subject to project-related reporting requirements and other project-specific covenants and events of default. If certain events occur, referred to as an "Alternate Amortization Event," at the Department of Energy's option the Federal Financing Bank's commitment to make further advances under the Facility will terminate and we will be required to repay the outstanding principal amount of all borrowings under the Facility over a period of five years, with level principal amortization. These events include (i) abandonment of the Vogtle Units No. 3 and No. 4 project, including a decision by Georgia Power to cancel the project, (ii) cessation of the construction of Vogtle Units No. 3 and No. 4 for twelve twelve b) Rural Utilities Service Guaranteed Loans: During 2020, we received advances on Rural Utilities Service-guaranteed Federal Financing Bank loans totaling $45,925,000 for long-term financing of general and environmental improvements at existing plants. In January 2021, we received an additional $238,578,000 in advances on Rural Utilities Service-guaranteed Federal Financing Bank loans for long-term financing of general and environmental improvements at existing plants. c) Credit Facilities: As of December 31, 2020, we had a total of $1,823,000,000 of committed credit arrangements comprised of four separate facilities with maturity dates that range from October 2021 to December 2024. These credit facilities are for general working capital purposes, issuing letters of credit and backing up outstanding commercial paper. Under our unsecured committed lines of credit that we had in place at December 31, 2020, we had the ability to issue letters of credit totaling $973,000,000 in the aggregate, of which $721,600,000 remained available. At December 31, 2020, we had (i) $252,000,000 under these lines of credit in the form of issued letters of credit supporting variable rate demand bonds and collateral postings to third parties, and (ii) $383,498,000 dedicated under one of these lines of credit to support a like amount of commercial paper that was outstanding. d) Lines of Credit: In mid-March 2020, due to significant disruptions in the commercial paper markets, we began to borrow directly under our $1.2 billion syndicated CFC line of credit in lieu of issuing commercial paper. During the second quarter of 2020, we repaid the borrowings under this line of credit with the proceeds of commercial paper we were able to issue as markets stabilized. On March 27, 2020, we amended our JPMorgan Chase line of credit, increasing the commitment from $150,000,000 to $363,000,000. On March 31, 2020, we borrowed $213,000,000 under this line of credit to purchase $212,760,000 of Series 2013 pollution control bonds that were subject to mandatory tender on April 1, 2020. On July 30, 2020, we repaid these borrowings utilizing proceeds from commercial paper issuances. e) Pollution Control Revenue Bonds: On August 25, 2020, we remarketed $212,760,000 of Series 2013A term rate pollution control revenue bonds that were subject to mandatory tender on April 1, 2020. The proceeds from the remarketing were used to repay outstanding commercial paper that was used to refinance the purchase of the Series 2013 bonds. The notes issued in connection with the Series 2013 bonds are secured under our first mortgage indenture. f) First Mortgage Bonds: On August 25, 2020, we issued $450,000,000 of 3.75% first mortgage bonds, Series 2020A for the purpose of providing long-term financing for expenditures related to the construction of Vogtle Units No. 3 and No. 4. In conjunction with the issuance, we repaid $439,200,000 of outstanding commercial paper. The bonds are due to mature August 2050 and are secured under our first mortgage indenture. |
Electric plant, construction an
Electric plant, construction and related agreements | 12 Months Ended |
Dec. 31, 2020 | |
Property, Plant and Equipment [Abstract] | |
Electric plant, construction and related agreements | Electric plant, construction and related agreements: a. Electric plant We, along with Georgia Power, have entered into agreements providing for the purchase and subsequent joint operation of certain electric generating plants. Each co-owner is responsible for providing their own financing. The plant investments disclosed in the table below represent our undivided interest in each plant. A summary of our plant investments and related accumulated depreciation as of December 31, 2020 and 2019 is as follows: 2020 2019 (dollars in thousands) Plant Investment Accumulated Investment Accumulated In-service (1) Owned property Vogtle Units No. 1 & No. 2 (Nuclear – 30% ownership) $ 3,008,848 $ (1,845,863) $ 2,989,693 $ (1,815,258) Vogtle Units No. 3 & No. 4 (Nuclear – 30% ownership) 57,631 (5,785) 56,991 (4,956) Hatch Units No. 1 & No. 2 (Nuclear – 30% ownership) 952,159 (479,628) 934,567 (462,063) Wansley Units No. 1 & No. 2 (2) (Fossil – 30% ownership) 764,315 (370,177) 749,971 (360,014) Scherer Unit No. 1 (Fossil – 60% ownership) 1,379,513 (569,357) 1,284,508 (545,908) Doyle (Combustion Turbine - 100% ownership) 139,853 (117,005) 137,513 (113,259) Rocky Mountain Units No. 1, No. 2 & No. 3 (Hydro – 75% ownership) 618,965 (281,763) 618,939 (270,058) Hartwell (Combustion Turbine - 100% ownership) 227,154 (113,879) 226,316 (110,008) Hawk Road (Combustion Turbine - 100% ownership) 263,673 (63,907) 260,494 (67,065) Talbot (Combustion Turbine - 100% ownership) 296,398 (152,859) 294,809 (144,847) Chattahoochee (Combined cycle - 100% ownership) 319,234 (160,194) 317,210 (150,805) Smith (Combined cycle - 100% ownership) 672,358 (174,176) 655,106 (195,638) Wansley (Combustion Turbine – 30% ownership) (2) 3,942 (3,847) 3,887 (3,738) Transmission plant 100,344 (60,688) 96,198 (59,096) Other 98,406 (60,904) 96,522 (57,826) Property under capital lease: Scherer Unit No. 2 (Fossil – 60% leasehold) 794,051 (508,262) 789,991 (472,486) Total in-service $ 9,696,844 $ (4,968,294) $ 9,512,715 $ (4,833,025) Construction work in progress Vogtle Units No. 3 & No. 4 $ 5,696,342 $ 4,617,654 Environmental and other 87,237 199,242 Total construction work in progress $ 5,783,579 $ 4,816,896 (1) Amounts include plant acquisition adjustments at December 31, 2020 and 2019 of $197,000,000. (2) Georgia Power is considering retiring Plant Wansley Units No. 1 and No. 2 as early as fall 2022. Although this decision has not been finalized or filed with the Georgia Public Service Commission, we are preparing for a scenario in which a retirement occurs in 2022; including seeking authorization to create a regulatory asset to defer a portion of the accelerated depreciation expense and recover the deferred costs over an extended period. Our proportionate share of direct expenses of joint operation of the above plants is included in the corresponding operating expense captions (e.g., fuel, production) on the accompanying Statement of Revenues and Expenses. b. Construction Vogtle Units No. 3 and No. 4 We, Georgia Power, the Municipal Electric Authority of Georgia, and the City of Dalton, Georgia, acting by and through its Board of Water, Light and Sinking Fund Commissioners, doing business as Dalton Utilities (collectively, the Co-owners) are parties to an Ownership Participation Agreement that, along with other agreements, governs our participation in two additional nuclear units under construction at Plant Vogtle, Units No. 3 and No. 4. The Co-owners appointed Georgia Power to act as agent under this agreement. Our ownership interest and proportionate share of the cost to construct these units is 30%. Pursuant to this agreement, Georgia Power has designated Southern Nuclear Operating Company, Inc. as its agent for licensing, engineering, procurement, contract management, construction and pre-operation services. In 2008, Georgia Power, acting for itself and as agent for the Co-owners, entered into an Engineering, Procurement and Construction Agreement (the EPC Agreement) with Westinghouse Electric Company LLC and Stone & Webster, Inc., which was subsequently acquired by Westinghouse and changed its name to WECTEC Global Project Services Inc. (collectively, Westinghouse). Pursuant to the EPC Agreement, Westinghouse agreed to design, engineer, procure, construct and test two 1,100 megawatt nuclear units using the Westinghouse AP1000 technology and related facilities at Plant Vogtle. Until March 2017, construction on Units No. 3 and No. 4 continued under the substantially fixed price EPC Agreement. In March 2017, Westinghouse filed for bankruptcy protection under Chapter 11 of the United States Bankruptcy Code. Effective in July 2017, Georgia Power, acting for itself and as agent for the other Co-owners, and Westinghouse entered into a services agreement (the Services Agreement), pursuant to which Westinghouse is providing facility design and engineering services, procurement and technical support and staff augmentation on a time and materials cost basis. The Services Agreement provides that it will continue until the start-up and testing of Vogtle Units No. 3 and No. 4 is complete and electricity is generated and sold from both units. The Services Agreement is terminable by the Co-owners upon 30 days' written notice. In October 2017, Georgia Power, acting for itself and as agent for the other Co-owners, entered into a construction completion agreement with Bechtel Power Corporation, pursuant to which Bechtel serves as the primary contractor for the remaining construction activities for Vogtle Units No. 3 and No. 4 (the Bechtel Agreement). The Bechtel Agreement is a cost reimbursable plus fee arrangement, whereby Bechtel is reimbursed for actual costs plus a base fee and an at-risk fee, which is subject to adjustment based on Bechtel's performance against cost and schedule targets. Each Co-owner is severally, and not jointly, liable for its proportionate share, based on its ownership interest, of all amounts owed to Bechtel under the Bechtel Agreement. The Co-owners may terminate the Bechtel Agreement at any time for their convenience, provided that the Co-owners will be required to pay amounts related to work performed prior to the termination (including the applicable portion of the base fee), certain termination-related costs and, at certain stages of the work, the applicable portion of the at-risk fee. Bechtel may terminate the Bechtel Agreement under certain circumstances, including certain Co-owner suspensions of work, certain breaches of the Bechtel Agreement by the Co-owners, Co-owner insolvency and certain other events. Our current budget for our 30% ownership interest in Vogtle Units No. 3 and No. 4 is $7.5 billion, which includes capital costs, allowance for funds used during construction, our allocation of the project-level contingency and a separate Oglethorpe-level contingency and is based on the Georgia Public Service Commission approved in-service dates of November 2021 and November 2022, respectively. As of December 31, 2020, our total investment in the additional Vogtle units was approximately $6.0 billion. We and some of our members have implemented various rate management programs to lessen the impact on rates when Vogtle Units No. 3 and No. 4 reach commercial operation. The Georgia Public Service Commission approved in-service dates for Vogtle Units No. 3 and No. 4 are November 2021 and November 2022, respectively. As part of its ongoing process, Southern Nuclear continues to evaluate cost and schedule forecasts on a regular basis to incorporate current information available, particularly in the areas of engineering support, commodity installation, system turnovers and related test results and workforce statistics. The August 2018 project-level budget included an $800 million construction contingency estimate, of which our 30% interest was $240 million. As of June 30, 2020, assignments of contingency exceeded the 2018 construction contingency estimate by $75 million (of which our 30% interest was $23 million) and Georgia Power established $250 million of additional construction contingency (of which our 30% interest is $75 million). During the third and fourth quarters of 2020, this construction contingency, plus an additional $10 million (of which our 30% interest was $3 million) was assigned to the base capital cost forecast. Assignment of contingency during 2020 addressed cost risks related to construction productivity, including the April 2020 reduction in workforce designed to mitigate impacts of the COVID-19 pandemic described below; other COVID-19 impacts; craft labor incentives; additional resources for supervision, field support, project management, initial test program, start-up, engineering support and operations and maintenance support; subcontracts; and procurement, among other factors. These factors continue to represent further potential cost risk to the project; therefore Georgia Power established $375 million of additional contingency as of December 31, 2020 (of which our 30% interest is $112.5 million). Georgia Power has stated its expectation to allocate the remainder of this project-level contingency by completion of the project. The project-level contingency is separate and in addition to our Oglethorpe-level contingency. The Oglethorpe-level contingency, which we have carried at various levels since the beginning of the project, was designed to cover potential cost, schedule, and financing risks associated with our share of the project which may not be covered by project-level contingencies. As construction progresses, the Oglethorpe-level contingency may continue to fluctuate as it represents the difference between known project-level costs and contingencies and our total budget of $7.5 billion. At the end of the project, if there is remaining Oglethorpe-level contingency, we will adjust our project budget to remove this contingency and bill our members based on the actual project costs. The table below shows our project budget and actual costs through December 31, 2020 for our 30% interest in the project. (in millions) Project Budget Actual Costs at December 31, 2020 Remaining Project Budget Construction Costs (1) $ 5,559 $ 4,754 $ 805 Financing Costs 1,578 1,259 319 Total Costs $ 7,137 $ 6,013 $ 1,124 Project-Level Contingency $ 113 $ — $ 113 Oglethorpe-Level Contingency 250 — 250 Total Contingency $ 363 $ — $ 363 Totals $ 7,500 $ 6,013 $ 1,487 (1) Construction costs are net of $1.1 billion received from Toshiba Corporation under a Guarantee Settlement Agreement. In mid-March 2020, Southern Nuclear began implementing policies and procedures designed to mitigate the risk of transmission of COVID-19 at the construction site, including worker distancing measures, isolating individuals who have tested positive for COVID-19, are showing symptoms consistent with COVID-19, are being tested for COVID-19, or have been in close contact with such persons, requiring self-quarantine, and adopting additional precautionary measures. In April 2020, Georgia Power, acting for itself and as agent for the other Co-owners, announced a reduction in workforce at Vogtle Units No. 3 and No. 4 and began reducing the then-existing site workforce by approximately 20%. This reduction in workforce was a mitigation action intended to address ongoing challenges with labor productivity that were exacerbated by the impact of the COVID-19 pandemic on the Vogtle Units No. 3 and No. 4 workforce and construction site by increasing productivity of the remaining workforce and reducing workforce fatigue and absenteeism. Further, it was also intended to allow for increased social distancing by the workforce and facilitate compliance with the recommendations from the Centers for Disease Control and Prevention. The April 2020 workforce reduction did reduce absenteeism, providing an improvement in operational efficiency and allowing for increased social distancing. Since April 2020, the number of active cases of COVID-19 at the site has fluctuated and continues to impact productivity levels and pace of the activity completion. From November 2020 through January 2021, the number of active COVID-19 cases at the site increased significantly, consistent with a national rise in cases, which further impacted productivity and the pace of activity completion. Although still present, this spike in cases has since abated into February and early March. The incremental cost associated with COVID-19 mitigation actions and impacts on construction productivity is currently estimated by Georgia Power to be between $325 and $415 million (of which our 30% interest is $98 to $125 million) and is included in the project budget. As described previously, Georgia Power included estimated costs associated with near-term COVID-19 mitigation actions and related impacts on construction productivity in the additional project-level contingency established as of December 31, 2020. The continuing effects of the COVID-19 pandemic could further disrupt or delay construction, testing, supervisory, and support activities at Vogtle Units No. 3 and No. 4. The project continues to face challenges, exacerbated by this recent rise in COVID-19 cases, including, but not limited to, higher than expected absenteeism; overall construction and subcontractor labor productivity; system turnover and testing activities; and electrical equipment and commodity installation. As a result of these factors, overall production levels were not achieved at the levels anticipated, contributing to the December 31, 2020 allocation of construction contingency and increase in total project capital cost forecast described previously. Southern Nuclear has further extended certain milestone dates, including the start of hot functional testing and fuel load for Unit No. 3. The Unit No. 3 schedule is challenged, and while the ability to achieve the November 2021 regulatory in-service date remains a target for Southern Nuclear, we believe a delay is likely which could add a month or more to the Unit No. 3 in-service date. As Unit No. 3 approaches hot functional testing, key factors impacting the schedule include both the pace of work package completion and system turnovers, and required construction remediation work Achievement of the November 2022 regulatory in-service date for Unit No. 4 primarily depends on overall construction productivity and production levels significantly improving as well as appropriate levels of craft laborers, particularly electrical and pipefitter craft labor, being added and maintained. In the event that there is any schedule extension beyond the November 2021 and November 2022 regulatory in-service dates for Units No. 3 and No. 4, respectively, the Oglethorpe-level contingency level in our current $7.5 billion budget is expected to be sufficient to withstand up to a 4-month delay for Unit No. 3 and a 3-month delay for Unit No. 4. Any further delays beyond these extended dates are expected to impact our cost by approximately $55 million per month for both units and approximately $25 million per month for Unit No. 4 only, including financing costs. As construction, including subcontract work, continues and testing and system turnover activities increase, risks remain that challenges with management of contractors and vendors; subcontractor performance; supervision of craft labor and related productivity, particularly in the installation of electrical, mechanical, and instrumentation and controls commodities, ability to attract and retain craft labor, and/or related cost escalation; procurement, fabrication, delivery, assembly, installation, system turnover, and the initial testing and start-up, including any required engineering changes or any remediation related thereto, of plant systems, structures or components (some of which are based on new technology that has only within the last few years began initial operation in the global nuclear industry at this scale), any of which may require additional labor and/or materials; or other issues could arise and further impact the projected schedule and estimated cost. There have been technical and procedural challenges to the construction and licensing of Vogtle Units No. 3 and No. 4 at the federal and state level and additional challenges may arise. Processes are in place that are designed to assure compliance with the requirements specified in the Westinghouse Design Control Document and the combined construction and operating licenses, including inspections by Southern Nuclear and the Nuclear Regulatory Commission that occur throughout construction. Findings from such inspections could require additional remediation and/or further Nuclear Regulatory Commission oversight. In addition, certain license amendment requests have been filed and approved or are pending before the Nuclear Regulatory Commission. On August 10, 2020, the Atomic Safety Licensing Board rejected the Blue Ridge Environmental Defense League’s May 11, 2020 petition challenging a license amendment request. The staff of the Nuclear Regulatory Commission has issued the requested amendment to the combined construction and operating license for Vogtle Unit No. 3. The Blue Ridge Environmental Defense League appealed the Atomic Safety Licensing Board’s decision to the Nuclear Regulatory Commission, which was denied on December 22, 2020. The Blue Ridge Environmental Defense League also filed a motion to reopen the proceeding and submitted an amended contention on December 7, 2020, which is pending before the Nuclear Regulatory Commission. Various design and other licensing-based compliance matters, including the timely submittal by Southern Nuclear of the inspections, tests, analyses, and acceptance criteria documentation for each unit and the related reviews and approvals by the Nuclear Regulatory Commission necessary to support authorization to load fuel, may arise, which may result in additional license amendments or require other resolution. If any license amendment requests or other licensing-based compliance issues, including inspections, tests, analyses, and acceptance criteria, are not resolved in a timely manner, there may be further delays in the project schedule that could result in increased costs to the Co-owners. The ultimate outcome of these matters cannot be determined at this time. c. Effingham County Power |
Employee benefit plans
Employee benefit plans | 12 Months Ended |
Dec. 31, 2020 | |
Retirement Benefits [Abstract] | |
Employee benefit plans | Employee benefit plans:Our retirement plan is a contributory 401(k) that covers substantially all employees. An employee may contribute, subject to IRS limitations, up to 60% of his or her eligible annual compensation. At our discretion, we may match the employee's contribution and have done so each year of the plan's existence. The match, which is calculated each pay period, currently can be equal to as much as three-quarters of the first 6% of an employee's eligible compensation, depending on the amount and timing of the employee's contribution. Our contributions to the matching feature of the plan were approximately $1,716,000, $1,632,000 and $1,497,000 in 2020, 2019 and 2018, respectively. Our 401(k) plan also includes an employer retirement contribution feature, which subject to IRS limitations, contributes 11% of an employee's eligible annual compensation. Our contributions to the employer retirement contribution feature of the 401(k) plan were approximately $4,371,000, $4,172,000 and $3,903,000 in 2020, 2019 and 2018, respectively. We also sponsor two deferred compensation plans for eligible employees. Eligible employees are defined as highly compensated individuals within the definition of the Internal Revenue Code. The plans offer investment options to all eligible participants without regard to salary limits. In addition, one plan enables us to continue employer retirement contributions to highly compensated employees who exceed Internal Revenue Code salary limits for retirement plan contributions. The value of the plans is recorded as an asset and an equal offsetting liability with balances of $4,716,000 and $3,440,000 in 2020 and 2019, respectively. |
Nuclear insurance
Nuclear insurance | 12 Months Ended |
Dec. 31, 2020 | |
Nuclear insurance: | |
Nuclear insurance | Nuclear insurance: The Price-Anderson Act limits public liability claims that could arise from a single nuclear incident to $13.8 billion. This amount is covered by private insurance and a mandatory program of deferred premiums that could be assessed against all owners of nuclear power reactors. Such private insurance provided by American Nuclear Insurers (ANI), is carried by Georgia Power for the benefit of all the co-owners of Plants Hatch and Vogtle. Agreements of indemnity have been entered into by and between each of the co-owners and the NRC. In the event of a nuclear incident involving any commercial nuclear facility in the country involving total public liability in excess of $450 million, a licensee of a nuclear power plant could be assessed a deferred premium of up to $138 million per incident for each licensed reactor operated by it, but not more than $20 million per reactor per incident to be paid in a calendar year. On the basis of our ownership interest in four nuclear reactors, we could be assessed a maximum of $165 million per incident, but not more than $25 million in any one year. Both the maximum assessment per reactor and the maximum yearly assessment are adjusted for inflation at least every 5 years, and exclude any applicable state premium taxes. The next scheduled adjustment is due no later than November 1, 2023. Georgia Power, on behalf of all the co-owners of Plants Hatch and Vogtle, is a member of Nuclear Electric Insurance, Ltd. (NEIL), a mutual insurer established to provide property damage insurance coverage in an amount up to $1.5 billion for members' operating nuclear generating facilities. Additionally, there is coverage through NEIL for decontamination, excess property insurance, and premature decommissioning coverage up to $1.25 billion for nuclear losses and policies providing coverage up to $750 million for non-nuclear losses in excess of the $1.5 billion primary coverage. Georgia Power, on behalf of all the co-owners has purchased a builders' risk property insurance policy from NEIL for Vogtle Units No. 3 and No. 4. This policy provides $2.75 billion in limits for accidental property damage occurring during construction. Under each of the NEIL policies, members are subject to retroactive assessments in proportion to their premiums, if losses each year exceed the accumulated reserve funds available to the insurer. The portion of the current maximum annual assessment for Georgia Power that would be payable by Oglethorpe based on ownership share, is limited to approximately $42 million. Claims resulting from terrorist acts and cyber events are covered under both the ANI and NEIL policies (subject to normal policy limits). The aggregate, however, that NEIL will pay for all claims resulting from terrorist acts in any 12-month period is $3.2 billion plus such additional amounts NEIL can recover through reinsurance, indemnity, or other sources. The aggregate that NEIL will pay for all claims resulting from cyber events in any 12-month period is $3.2 billion plus such additional amounts NEIL can recover through reinsurance, indemnity, or other sources. For all on-site property damage insurance policies for commercial nuclear power plants, the NRC requires that the proceeds of such policies shall be dedicated first for the sole purpose of placing the reactor in a safe and stable condition after an accident. Any remaining proceeds are next to be applied toward the costs of decontamination and debris removal operations ordered by the NRC, and any further remaining proceeds are to be paid either to Georgia Power, for the benefit of all the co-owners, or to bond trustees as may be appropriate under the policies and applicable trust indentures. |
Commitments
Commitments | 12 Months Ended |
Dec. 31, 2020 | |
Commitments and Contingencies Disclosure [Abstract] | |
Commitments | Commitments: We have entered into long-term commitments to meet fuel, transportation, maintenance and asset retirement requirements. To supply a portion of the fuel requirements to our co-owned generating units, Georgia Power, on our behalf for coal and Southern Nuclear on our behalf for nuclear fuel, have entered into various long-term commitments for the procurement of coal and nuclear fuel. The contracts in most cases contain provision for price escalations, minimum and maximum purchase levels and other financial commitments. The value of the coal commitments is based on maximum coal prices and minimum volumes as provided in the contracts and does not include taxes, transportation, government impositions or railcar costs. We have entered into long-term agreements with various counterparties to provide firm natural gas transportation to our natural gas-fired facilities. The value of these agreements is based on fixed rates as provided in the contracts and does not include variable costs. We have also entered into long-term maintenance agreements for certain of our natural gas-fired facilities. In most cases, these agreements include provisions for price escalation and performance bonuses and, if applicable, are included in the values; timing of expenditures is based on current operational assumptions. Certain agreements contain significant cancellation for convenience penalties and, therefore, amounts in the table below include total estimated expenditures over the life of the agreement. If these agreements were terminated by us in 2021 for convenience, our cancellation obligation would be approximately $54,007,000. We have asset retirement obligations which are legal obligations to retire long-lived assets. These obligations are primarily for the decommissioning of our nuclear units and coal ash ponds. Expenditures are based on estimates determined through decommissioning studies and include provisions for price escalation and other factors. See Note 1h for information regarding our asset retirement obligations. We have a small portfolio of leases with the most significant being a finance lease for our 60% undivided interest in Scherer Unit No. 2. In addition, we have other operating leases including railcar leases for the transportation of coal at our coal-fired plants and various other leases of minimal value. For information regarding these leases, see Note 6. As of December 31, 2020, our estimated commitments are as follows: (dollars in thousands) Coal Nuclear Fuel Gas Maintenance Asset Finance and Operating Leases 2021 $ 5,168 $ 73,500 $ 63,385 $ 14,429 $ 17,821 $ 16,068 2022 3,017 33,060 53,268 14,896 31,780 15,878 2023 — 17,340 48,707 3,325 34,372 15,657 2024 — 22,650 48,034 30,316 41,840 15,183 2025 — 11,250 46,350 43,212 74,077 15,021 Thereafter — 15,930 746,160 176,751 3,400,140 41,595 |
Contingencies and Regulatory Ma
Contingencies and Regulatory Matters | 12 Months Ended |
Dec. 31, 2020 | |
Contingencies and Regulatory Matters: | |
Contingencies and Regulatory Matters | Contingencies and Regulatory Matters:We do not anticipate that the liabilities, if any, for any current proceedings against us will have a material effect on our financial condition or results of operations. However, at this time, the ultimate outcome of any pending or potential litigation cannot be determined. Environmental Matters As is typical for electric utilities, we are subject to various federal, state and local environmental laws which represent significant future risks and uncertainties. Air emissions, water discharges and water usage are extensively controlled, closely monitored and periodically reported. Handling and disposal requirements govern the manner of transportation, storage and disposal of various types of waste. We are also subject to climate change regulations that impose restrictions on emissions of greenhouse gases, including carbon dioxide. Such requirements may substantially increase the cost of electric service, by requiring modifications in the design or operation of existing facilities or the purchase of emission allowances. Failure to comply with these requirements could result in civil and criminal penalties and could include the complete shutdown of individual generating units not in compliance. Certain of our debt instruments require us to comply in all material respects with laws, rules, regulations and orders imposed by applicable governmental authorities, which include current and future environmental laws or regulations. Should we fail to be in compliance with these requirements, it would constitute a default under those debt instruments. We believe that we are in compliance with those environmental regulations currently applicable to our business and operations. Although it is our intent to comply with current and future regulations, we cannot provide assurance that we will always be in compliance. The ultimate impact of any environmental regulations is uncertain and could have an effect on our financial condition, results of operations and cash flows as a result of future additional capital expenditures and increased operations and maintenance costs. Additionally, litigation over environmental issues and claims of various types, including property damage, personal injury, common law nuisance, and citizen enforcement of environmental requirements such as air quality and water standards, has increased generally throughout the United States. In particular, personal injury and other claims for damages caused by alleged exposure to hazardous materials, and common law nuisance claims for injunctive relief, personal injury and property damage allegedly caused by coal combustion residue, greenhouse gas and other emissions have become more frequent. On July 29, 2020, a group of individual plaintiffs filed a complaint in the Superior Court of Fulton County, Georgia against Georgia Power alleging that releases from Plant Scherer, of which we are a co-owner, have impacted groundwater, surface water, and air, resulting in alleged personal injuries and property damage. The plaintiffs seek an unspecified amount of monetary damages including punitive damages, a medical monitoring fund, and injunctive relief. |
Quarterly financial data (unaud
Quarterly financial data (unaudited) | 12 Months Ended |
Dec. 31, 2020 | |
Quarterly Financial Data [Abstract] | |
Quarterly financial data (unaudited) | Quarterly financial data (unaudited): Summarized quarterly financial information for 2020 and 2019 is as follows: First Second Third Fourth (dollars in thousands) 2020 Operating revenues $ 341,674 $ 330,944 $ 366,239 $ 338,761 Operating margin 62,515 65,532 47,862 41,800 Net margin 23,204 26,162 8,471 (1,942) 2019 Operating revenues $ 356,600 $ 358,860 $ 382,623 $ 332,209 Operating margin 66,032 51,712 59,209 40,256 Net margin 23,596 9,383 18,286 3,196 The negative net margins in the fourth quarter of 2020 were due to reductions to revenue requirements in order to achieve, but not exceed, the targeted margins for interest ratio of 1.14. |
Summary of significant accoun_2
Summary of significant accounting policies (Policies) | 12 Months Ended |
Dec. 31, 2020 | |
Accounting Policies [Abstract] | |
Business description | Business descriptionOglethorpe Power Corporation is an electric membership corporation incorporated in 1974 and headquartered in metropolitan Atlanta, Georgia that operates on a not-for-profit basis. We are owned by 38 retail electric distribution cooperative members in Georgia. We provide wholesale electric power from a combination of owned and co-owned generating units of which our ownership share totals 7,125 megawatts of summer planning reserve capacity. We also manage and operate Smarr EMC which owns 737 megawatts of summer planning reserve capacity. In addition, we supply financial and management services to Green Power EMC, which purchases energy from renewable energy facilities totaling 320 megawatts of capacity, including 288 megawatts sourced by solar energy. Georgia Power Company is a co-owner and the operating agent of our nuclear and coal-fired generating units. Our members in turn distribute energy on a retail basis to approximately 4.3 million people. |
Basis of accounting | Basis of accounting Our consolidated financial statements include our accounts and the accounts of our majority-owned and controlled subsidiary. We have determined that there are no accounts of variable interest entities for which we are the primary beneficiary. We have eliminated any intercompany profits and transactions in consolidation. We follow generally accepted accounting principles in the United States. We maintain our accounts in accordance with the Uniform System of Accounts of the Federal Energy Regulatory Commission as modified and adopted by the Rural Utilities Service. We also apply the accounting guidance for regulated operations. The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of December 31, 2020 and 2019 and the reported amounts of revenues and expenses for each of the three years in the period ended December 31, 2020. Examples of estimates used include items related to our asset retirement obligations. Accounting for asset retirement and environmental obligations requires legal obligations associated with the retirement of long-lived assets to be recognized at fair value when incurred and capitalized as part of the related long-lived asset. In the absence of quoted market prices, we estimate the fair value of our asset retirement obligations using present value techniques, in which estimates of future cash flows associated with retirement activities are discounted using a credit-adjusted risk-free rate. Estimating the amount and timing of future expenditures includes, among other things, making projections of when assets will be retired and ultimately decommissioned, the amount of decommissioning costs, and how costs will escalate with inflation. Actual results could differ from those estimates. |
Patronage capital and membership fees | Patronage capital and membership fees We are organized and operate as a cooperative. Our members paid a total of $190 in membership fees. Patronage capital includes retained net margin. Any excess of revenues over expenditures from operations is treated as an advance of capital by our members and is allocated to each member on the basis of their fixed percentage capacity cost responsibilities in our generation. Any distributions of patronage capital are subject to the discretion of our board of directors, subject to first mortgage indenture requirements. Under our first mortgage indenture, we are prohibited from making any distribution of patronage capital to our members if, at the time of or after giving effect to, (i) an event of default exists under the indenture, (ii) our equity as of the end of the immediately preceding fiscal quarter is less than 20% of our total long-term debt and equities, or (iii) the aggregate amount expended for distributions on or after the date on which our equity first reaches 20% of our total long-term debt and equities exceeds 35% of our aggregate net margins earned after such date. This last restriction, however will not apply if, after giving effect to such distribution, our equity as of the end of the immediately preceding fiscal quarter is not less than 30% of our long-term debt and equities. |
Margin policy | Margin policyWe are required under our first mortgage indenture to produce a margins for interest ratio of at least 1.10 for each fiscal year. |
Revenue recognition and Deferred credits and other liabilities | Revenue recognition As an electric membership cooperative, our principal business is providing wholesale electric service to our members. Our operating revenues are derived primarily from wholesale power contracts we have with each of our 38 members. These contracts, which extend to December 31, 2050, are substantially identical and obligate our members jointly and severally to pay all expenses associated with owning and operating our power supply business. As a cooperative, we operate on a not-for-profit basis and, accordingly, seek only to generate revenues sufficient to recover our cost of service and to generate margins sufficient to establish reasonable reserves and meet certain financial coverage requirements. While not significant, we also have short-term energy sales to non-members made through industry standard contracts. We do not have multiple operating segments. Pursuant to our contracts, we primarily provide two services, capacity and energy. Capacity and energy revenues are recognized by us upon transfer of control of promised services to our members and non-members in an amount that reflects the consideration we expect to receive in exchange for those services. Capacity and energy are distinct and we account for them as separate performance obligations. The obligations to provide capacity and energy are satisfied over time as the customer simultaneously receives and consumes the benefit of these services. Both performance obligations are provided directly by us and not through a third party. Each of our members is obligated to pay us for capacity and energy we furnish under its wholesale power contract in accordance with rates we establish. We review our rates periodically but are required to do so at least once every year. Revenues from our members are derived through a cost-plus rate structure which is set forth as a formula in the rate schedule to the wholesale power contracts. The formulary rate provides for the pass-through of our (i) fixed costs (net of any income from other sources) plus a targeted margin as capacity revenues and (ii) variable costs as energy revenues from our members. Power purchase and sale agreements between us and non-members obligate each non-member to pay us for capacity, if any, and energy furnished in accordance with the prices mutually agreed upon. Margins produced from non-member sales are included in our rate schedule formula and reduce revenue requirements from our members. The consideration we receive for providing capacity services is determined by our formulary rate on an annual basis. The components of the formulary rate associated with capacity costs include the annual budget of fixed costs, a targeted margin and income from other sources. Capacity revenues, therefore, vary to the extent these components vary. Fixed costs include items such as fixed operation and maintenance expenses, administrative and general expenses, depreciation and interest. Year to year, capacity revenue fluctuations are generally due to the recovery of fixed operation and maintenance expenses. Fixed costs also include certain costs, such as major maintenance costs, which will be recognized as expense in future periods. Recognition of revenues associated with these future expenses is deferred pursuant to Accounting Standards Codification (ASC) 980, Regulated Operations. The regulatory liabilities are amortized to revenue in accordance with the associated revenue deferral plan as the expenses are recognized. For information regarding regulatory accounting, see Note 1q. Capacity revenues are recognized by us for standing ready to deliver electricity to our customers. Our capacity revenues are based on the associated costs we expect to recover in a given year and are recognized and billed to our members in equal monthly installments over the course of the year regardless of whether our generation and purchased power resources are dispatched to produce electricity. Non-member capacity revenues, if any, are typically billed and recognized in equal monthly installments over the term of the contract. We have a power bill prepayment program pursuant to which our members may prepay future capacity costs and receive a discount. As this program provides us with financing, we adjust our capacity revenues by the amount of the discount, which is based on our avoided cost of borrowing. For additional information regarding our member prepayment program, see Note 1p. We satisfy our performance obligations to deliver energy as energy is delivered to the applicable meter points. We determine the standard selling price for energy we deliver to our members based upon the variable costs incurred to generate or purchase that energy. Fuel expense is the primary variable cost. Energy revenue recognized equals the actual variable expenses incurred in any given accounting period. Our member energy revenues fluctuate from period to period based on several factors, including fuel costs, weather and other seasonal factors, load requirements in our members’ service territories, variable operating costs, the availability of electric generation resources, our decisions of whether to dispatch our owned or Electric capacity and energy revenues are recognized by us without any obligation for returns, warranties or taxes collected. As our members are jointly and severally obligated to pay all expenses associated with owning and operating our power supply business and we perform an on-going assessment of the credit worthiness of non-members, we have not recorded an allowance for doubtful accounts associated with our receivables from members or non-members. We have a rate management program that allows us to expense and recover interest costs on a current basis that would otherwise be deferred or capitalized. The subscribing members of Vogtle Units No. 3 and No. 4 can elect to participate in this program on an annual basis. The Vogtle program allows for the recovery of financing costs associated with the construction of Vogtle Units No. 3 and No. 4 on a current basis. Under this program, amounts billed to participating members in 2020, 2019 and 2018 were $14,684,000, $14,943,000 and $12,229,000, respectively. The cumulative amount billed since inception of the program totaled $95,943,000. In 2018, we began an additional rate management program that allows us to recover future expense on a current basis from our members. In general, the program allows for additional collections over a five |
Receivables | Receivables A substantial portion of our receivables are related to capacity and energy sales to our members. These receivables are recorded at the invoiced amount and do not bear interest. Our members are required through the wholesale power contracts to reimburse us for all costs, plus a margin requirement. Receivables from contracts with our members at December 31, 2020, 2019 and 2018 were $135,462,000, $142,946,000 and $122,888,000, respectively. Payment is typically received the following month in which capacity and energy are billed. Estimated energy charges are billed based on the amount of energy supplied during the month and are adjusted when actual costs are available, generally the following month. The remainder of our receivables is primarily related to transactions with affiliated companies and investment income. |
Nuclear fuel cost | Nuclear fuel costThe cost of nuclear fuel is amortized to fuel expense based on usage. |
Asset retirement obligations and other retirement costs | Asset retirement obligations and other retirement costsAsset retirement obligations are legal obligations associated with the retirement of long-lived assets. These obligations represent the present value of the estimated costs for an asset's future retirement discounted using a credit-adjusted risk-free rate, and are recorded in the period in which the liability is incurred. The liabilities we have recognized primarily relate to the decommissioning of our nuclear facilities and coal ash ponds. In addition, we have retirement obligations related to gypsum cells, powder activated carbon cells, landfill sites and asbestos removal. Under the accounting provision for regulated operations, we record a regulatory asset or liability to reflect the difference in timing of recognition of the costs related to nuclear and coal ash related decommissioning for financial statement purposes and for ratemaking purposes. Periodically, we obtain revised cost studies associated with our nuclear and fossil plants' asset retirement obligations. Actual retirement costs may vary from these estimates. The estimated costs of nuclear and coal ash pond decommissioning are based on the most recent studies performed in 2018 and 2019, respectively. We apply the provision of regulated operations to nuclear decommissioning transactions such that collections and investment income (interest, dividends and realized gains and losses) of our nuclear decommissioning funds are compared to the associated decommissioning expenses with the difference deferred as regulatory asset or liability. As this difference is largely attributable to the timing of decommissioning fund earnings, the difference is recorded as an adjustment to investment income in our consolidated statements of revenues and expenses. Unrealized gains and losses of the decommissioning funds are recorded directly to the regulatory asset or liability for asset retirement obligations in accordance with our ratemaking treatment. Coal Combustion Residuals. Coal combustion residuals (CCR) are subject to Federal and State regulations. Our obligations associated with CCR are primarily for the closure of coal ash ponds. During 2020 and 2019, assessments of the coal ash pond asset retirement obligation resulted in a $10,775,000 increase and a $5,958,000 decrease in the obligation for coal ash decommissioning, respectively. Estimates are based on various assumptions including, but not limited to, closure and post-closure cost estimates, timing of expenditures, escalation factors, discount rates and methods for complying with the CCR regulations. Additional adjustments to the asset retirement obligations are expected periodically due to potential changes in estimates and assumptions. We have internally segregated the funds collected for coal ash pond and landfill decommissioning costs, including earnings thereon. As of December 31, 2020 and December 31, 2019 the fund balances were $120,536,000 and $93,184,000, respectively. We apply the provision of regulated operations to coal ash pond and landfill decommissioning transactions such that collections and investment income (interest, dividends and realized gains and losses) are compared to the associated decommissioning expenses with the difference deferred to or amortized from the regulatory asset. This difference is recorded to the associated expenses in our consolidated statements of revenues and expenses. Unrealized gains and losses of the associated decommissioning fund are recorded directly to the regulatory asset in accordance with our ratemaking treatment. Other Retirement Costs |
Nuclear decommissioning funds | Nuclear decommissioning fundsThe Nuclear Regulatory Commission (NRC) requires all licensees operating commercial power reactors to establish a plan for providing, with reasonable assurance, funds for decommissioning. The NRC definition of decommissioning does not include all costs that may be associated with decommissioning, such as spent fuel management and non-radiated structures. We have established external trust funds to comply with the NRC's regulations. Upon approval by the NRC, any funding in the external trust in excess of their requirements may be used for other decommissioning costs. In 2020 and 2019, no additional amounts were contributed to the external trust funds. These funds are managed by unrelated third party investment managers with the discretion to buy, sell and invest pursuant to investment objectives and restrictions set forth in agreements entered into between us and the investment managers. We record the investment securities held in the nuclear decommissioning trust fund at fair value, as disclosed in Note 2. Because day-to-day investment decisions are made by third party investment managers, the ability to hold investments in unrealized loss positions is outside our control.In addition to the external trust funds, we maintain unrestricted investments internally designated for nuclear decommissioning. These internal funds are available to be utilized to fund the external trust funds, should additional funding be required, as well as other decommissioning costs outside the scope of the NRC funding regulations. The funds are included in long-term investments on our consolidated balance sheet.Realized and unrealized gains and losses of the nuclear decommissioning funds that would be recorded in earnings by a non-regulated entity are directly deducted from or added to the regulatory asset or liability for asset retirement obligations in accordance with our rate-making treatment. |
Depreciation | DepreciationDepreciation is computed on additions when they are placed in service using the composite straight-line method. We use standard depreciation rates as well as site specific rates determined through depreciation studies as approved by the Rural Utilities Service. The depreciation rates for steam and nuclear production in the table below reflect revised rates from depreciation rate studies completed in 2015. Site specific depreciation studies are performed every five years. |
Electric plant | Electric plant Electric plant is stated at original cost, which is the cost of the plant when first dedicated to public service, including acquisition adjustments, if any, plus the cost of any subsequent additions. Cost includes an allowance for the cost of equity and debt funds used during construction and allocable overheads. For the years 2020, 2019 and 2018, the allowance for funds used during construction rates were 4.00%, 4.30% and 4.25%, respectively. Replacements and renewals of items considered to be units of property, the lowest level of property for which we capitalize, are charged to the plant accounts. At the time properties are disposed of, the original cost is charged to the accumulated provision for depreciation. Cost of removal, less salvage, is charged to a regulatory liability, accumulated retirement costs for other assets. Maintenance and repairs of property and replacements and renewals of items determined to be less than units of property are charged to expense, including certain major maintenance costs at our natural gas-fired plants. |
Cash and cash equivalents | Cash and cash equivalentsWe consider all temporary cash investments purchased with an original maturity of three months or less to be cash equivalents. Temporary cash investments with maturities at the time of purchase of more than three months are classified as short-term investments. |
Restricted investments | Restricted investmentsRestricted investments consist of funds on deposit with the Rural Utilities Service in the Cushion of Credit Account that are held by the U.S. Treasury, acting through the Federal Financing Bank. We can only utilize these investments for future Rural Utilities Service-guaranteed Federal Financing Bank debt service payments. Through September 30, 2020 funds earned interest at a rate of 5% per annum. Beginning October 1, 2020, deposits earn interest at 4% per annum and beginning October 1, 2021, the rates will be set at the 1-year floating treasury rate. The program no longer allows additional funds to be deposited into the account. At December 31, 2020 and 2019, we had restricted investments totaling $487,587,000 and $533,590,000, respectively, of which $306,601,000 and $461,757,000, respectively, were classified as long-term. |
Inventories | InventoriesWe maintain inventories of fossil fuel and spare parts, including materials and supplies for our generation plants. These inventories are stated at weighted average cost.The fossil fuel inventories primarily include the direct cost of coal and related transportation charges. The cost of fossil fuel inventories is carried at weighted average cost and is charged to fuel expense as consumed. The spare parts inventories primarily include the direct cost of generating plant spare parts. The spare parts inventory is carried at weighted average cost and the parts are charged to expense or capitalized, as appropriate when installed. |
Deferred charges and other assets | Deferred charges and other assetsOther deferred charges primarily represent advance deposits to Georgia Power Company related to the Vogtle construction project and future generation project costs. |
Regulatory assets and liabilities | Regulatory assets and liabilitiesWe apply the accounting guidance for regulated operations. Regulatory assets represent certain costs that are probable of recovery from our members in future revenues through rates established under the wholesale power contracts we have with each of our members. These contracts extend through December 31, 2050. Regulatory liabilities represent certain items of income that we are retaining and that will be applied in the future to reduce revenues required to be recovered from members. |
Related parties | Related partiesWe and our 38 members are members of Georgia Transmission. Georgia Transmission provides transmission services to its members for delivery of its members' power purchases from us and other power suppliers. We have entered into an agreement with Georgia Transmission to provide transmission services for third party transactions and for service to our owned facilities. For 2020, 2019, and 2018, we incurred expenses from Georgia Transmission of $37,931,000, $37,156,000 and $30,428,000, respectively.We, Georgia Transmission and 38 of our members are members of Georgia Systems Operations. Georgia Systems Operations operates the system control center and currently provides us system operations services and administrative support services. |
Other income | Other incomeOther income includes net revenue from Georgia Transmission and Georgia Systems Operations for administrative costs, as well as capital credits from investments in associated organizations and other miscellaneous income. |
Recently issued or adopted accounting pronouncements | Recently issued or adopted accounting pronouncements In March 2020, the Financial Accounting Standards Board (FASB) issued “Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting”. The amendments in this update apply to all entities that have contracts, hedging relationships, and other transactions that reference London Interbank Offered Rate (LIBOR) or another reference rate expected to be discontinued because of reference rate reform. The amendments in this update provide optional expedients and exceptions for applying U.S. GAAP to transactions affected by reference rate reform if certain criteria are met. The expedients and exceptions provided by the amendments in this update do not apply to contract modifications made and hedging relationships entered into or evaluated after December 31, 2022, except for hedging relationships existing as of December 31, 2022, for which an entity has elected certain optional expedients that are retained through the end of the hedging relationship. In January 2021, the FASB issued “Reference Rate Reform (Topic 848): Scope,” to further clarify the scope of the reference rate reform guidance in Topic 848. The amendments in this update refine the scope of Topic 848 to clarify that certain optional expedients and exceptions therein for contract modifications and hedge accounting apply to contracts that are affected by the discounting transition. Specifically, modifications related to reference rate reform would not be considered an event that requires reassessment of previous accounting conclusions. The amendments in this update also amend the expedients and exceptions in Topic 848 to capture the incremental consequences of the scope clarification and to tailor the existing guidance to derivative instruments affected by the discounting transition. The amendments in these updates are effective for all entities as of March 12, 2020 through December 31, 2022. We are currently evaluating the future impact of this standard on our consolidated financial statements.. In June 2016, the FASB issued "Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments." The standard was effective for us prospectively for annual reporting periods beginning after December 15, 2019, and interim periods therein. On January 1, 2020, we adopted this standard. The standard requires consideration of a broad range of information to estimate expected credit losses over the lifetime of financial assets measured at amortized cost. The new credit losses standard replaced the “incurred loss” methodology for recognizing credit losses that delayed recognition until it was probable a loss had been incurred. The financial assets we hold that are subject to the new standard are predominately accounts receivable and certain cash equivalents classified as held-to-maturity debt (e.g. commercial paper). Our receivables are generally due within thirty days or less with a significant portion related to billings to our members. See Notes 1e and 1f for information regarding our member receivables. Commercial paper issuances we invest in are rated as investment grade and backed by a credit facility. Given our historical experience, the short duration lifetime of these financial assets and the short time horizon over which to consider expectations of future economic conditions, we have assessed that non-collection of the cost basis of these financial assets is remote. The adoption of the standard did not materially impact our consolidated financial statements. In August 2018, the FASB issued "Fair Value Measurement (Topic 820): Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement." This standard eliminated, added and modified certain disclosure requirements for fair value measurements as part of the FASB's disclosure framework project. Entities are no longer required to disclose the amount of and reasons for transfers between Level 1 and Level 2 of the fair value hierarchy, the policy for timing of transfers between levels and the valuation processes for Level 3 fair value measurements. However, public business entities are required to disclose the range and weighted average of significant unobservable inputs used to develop Level 3 fair value measurements. The amendments in this update were effective for all entities for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2019. An entity was permitted to early adopt any removed or modified disclosures upon issuance of this update and delay adoption of the additional disclosures until their effective date. The adoption of the standard did not have a material impact on our consolidated financial statements. In December 2019, the FASB issued “Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes”, as part of its initiative to reduce complexity in the accounting standards. The amendments in the standard remove certain exceptions and also clarify and simplify various aspects of accounting for income taxes. The new standard is effective for us prospectively for annual reporting periods beginning after December 15, 2020, and interim periods therein. Early adoption is permitted, which we are not electing to do. The adoption of this standard on January 1, 2021 is not expected to have a material impact on our consolidated financial statements. |
Summary of significant accoun_3
Summary of significant accounting policies (Tables) | 12 Months Ended |
Dec. 31, 2020 | |
Accounting Policies [Abstract] | |
Schedule of sales to members | Sales to members were as follows: (dollars in thousands) 2020 2019 2018 Capacity revenues $ 971,071 $ 942,057 $ 927,419 Energy revenues 405,939 487,795 551,960 Total $ 1,377,010 $ 1,429,852 $ 1,479,379 |
Schedule of members whose revenues accounted for 10% or more of total operating revenues | The following table reflects members whose revenues accounted for 10% or more of our total operating revenues in 2020, 2019 or 2018: 2020 2019 2018 Jackson EMC 15.2 % 14.4 % 14.1 % Cobb EMC 13.2 % 13.8 % 13.9 % |
Schedule reflecting details of asset retirement obligations included in the consolidated balance sheets | The following table reflects the details of the asset retirement obligations included in the consolidated balance sheets for the years 2020 and 2019. (dollars in thousands) Nuclear Coal Ash Pond Other Total Balance at December 31, 2019 $ 697,441 $ 329,264 $ 43,935 1,070,640 Liabilities settled — (4,656) (2,332) (6,988) Accretion 40,776 12,059 1,640 54,475 Deferred accretion — (853) — (853) Change in cash flow estimates — 10,775 7,934 18,709 Balance at December 31, 2020 $ 738,217 $ 346,589 $ 51,177 $ 1,135,983 (dollars in thousands) Nuclear Coal Ash Pond Other Total Balance at December 31, 2018 $ 658,956 $ 326,248 $ 32,359 $ 1,017,563 Liabilities settled — (3,380) (1,158) (4,538) Accretion 38,485 10,494 1,494 50,473 Deferred accretion — 1,860 — 1,860 Change in cash flow estimates — (5,958) 11,240 5,282 Balance at December 31, 2019 $ 697,441 $ 329,264 $ 43,935 $ 1,070,640 |
Schedule of estimated costs of decommissioning of co-owned nuclear facilities | Our portion of the estimated costs of decommissioning co-owned nuclear facilities are as follows: (dollars in thousands) 2018 site study Hatch Hatch Vogtle Vogtle Expected start date of decommissioning 2034 2038 2047 2049 Estimated costs based on site study in 2018 dollars: Radiated structures $ 209,000 $ 231,000 $ 188,000 $ 206,000 Spent fuel management 54,000 49,000 55,000 51,000 Non-radiated structures 14,000 19,000 23,000 29,000 Total estimated site study costs $ 277,000 $ 299,000 $ 266,000 $ 286,000 |
Schedule of external and internal trust funds by type of investment | The following table outlines the fair value of our nuclear decommissioning funds as of December 31, 2020 and December 31, 2019. The funds were invested in a diversified mix of approximately 64% equity and 36% fixed income securities in 2020 and 2019. 2020 External Trust Funds: (dollars in thousands) Cost Purchases Net Proceeds(1) Unrealized Gain(Loss) Fair Value 12/31/2020 Equity $ 212,585 $ 27,707 $ (16,444) $ 177,866 $ 401,714 Debt 174,645 536,147 (523,926) 11,100 197,966 Other (702) 14,756 (15,553) — (1,499) $ 386,528 $ 578,610 $ (555,923) $ 188,966 $ 598,181 (1) Also included in net proceeds are net realized gains or losses, interest income, dividends and fees of $22,686,000. 2020 Internal Funds: (dollars in thousands) Cost Purchases Net Unrealized Fair Value Equity $ 47,062 $ — $ 3,586 $ 33,665 $ 84,313 Debt 44,347 132,710 (126,590) 2,519 52,986 $ 91,409 $ 132,710 $ (123,004) $ 36,184 $ 137,299 (1) Also included in net proceeds are net realized gains or losses, interest income, dividends, contributions and fees of $9,705,000. 2019 External Trust Funds: (dollars in thousands) Cost Purchases Net Unrealized Fair Value Equity $ 207,313 $ 11,950 $ (6,678) $ 119,263 $ 331,848 Debt 166,023 361,844 (353,222) 5,548 180,193 Other 115 544 (1,361) — (702) $ 373,451 $ 374,338 $ (361,261) $ 124,811 $ 511,339 (1) Also included in net proceeds are net realized gains or losses, interest income, dividends and fees of $13,078,000. 2019 Internal Funds: (dollars in thousands) Cost Purchases Net Unrealized Fair Value Equity $ 44,295 $ — $ 2,767 $ 19,578 $ 66,640 Debt 38,382 140,997 (135,033) 1,161 45,507 $ 82,677 $ 140,997 $ (132,266) $ 20,739 $ 112,147 (1) Also included in net proceeds are net realized gains or losses, interest income, dividends, contributions and fees of $8,732,000. |
Schedule of annual depreciation rates | Annual weighted average depreciation rates in effect in 2020, 2019, and 2018 were as follows: Range of 2020 2019 2018 Steam production 49-65 2.58 % 2.61 % 2.57 % Nuclear production 37-60 1.93 % 1.94 % 1.92 % Hydro production 50 2.00 % 2.00 % 2.00 % Other production 25-35 2.61 % 2.61 % 2.61 % Transmission 36 2.75 % 2.75 % 2.75 % General 3-50 2.00-33.33% 2.00-33.33% 2.00-33.33% * Calculated based on the composite depreciation rates in effect for 2020. |
Schedule of regulatory assets and liabilities | Regulatory liabilities represent certain items of income that we are retaining and that will be applied in the future to reduce revenues required to be recovered from members. (dollars in thousands) 2020 2019 Regulatory Assets: Premium and loss on reacquired debt(a) $ 35,433 $ 40,067 Amortization on financing leases(b) 35,328 35,433 Outage costs(c) 35,232 34,367 Asset retirement obligations – Ashpond and other(k) 242,832 245,932 Depreciation expense(d) 38,396 39,820 Deferred charges related to Vogtle Units No. 3 and No. 4 training costs(e) 55,430 53,466 Interest rate options cost(f) 126,813 121,938 Deferral of effects on net margin – Smith Energy Facility(g) 148,620 154,564 Other regulatory assets(m) 13,354 37,925 Total Regulatory Assets $ 731,438 $ 763,512 Regulatory Liabilities: Accumulated retirement costs for other obligations(h) $ 20,054 $ 12,692 Deferral of effects on net margin – Hawk Road Energy Facility(g) 17,869 18,485 Major maintenance reserve(i) 39,776 50,144 Amortization on financing leases(b) 11,356 14,256 Deferred debt service adder(j) 123,772 114,453 Asset retirement obligations – Nuclear(k) 130,901 61,516 Revenue deferral plan(l) 220,111 90,066 Other regulatory liabilities(m) 2,560 2,629 Total Regulatory Liabilities $ 566,399 $ 364,241 Net regulatory assets $ 165,039 $ 399,271 (a) Represents premiums paid, together with unamortized transaction costs related to reacquired debt that are being amortized over the lives of the refunding debt, which range up to 23 years. (b) Represents the difference between expense recognized for rate-making purposes versus financial statement purposes related to finance lease payments and the aggregate of the amortization of the asset and interest on the obligation. (c) Consists of both coal-fired maintenance and nuclear refueling outage costs. Coal-fired outage costs are amortized on a straight-line basis to expense over periods up to 60 months, depending on the operating cycle of each unit. Nuclear refueling outage costs are amortized on a straight-line basis to expense over the 18 or 24-month operating cycles of each unit. (d) Prior to Nuclear Regulatory Commission (NRC) approval of a 20-year license extension for Plant Vogtle, we deferred the difference between Plant Vogtle depreciation expense based on the then 40-year operating license and depreciation expense assuming an expected 20-year license extension. Amortization commenced upon NRC approval of the license extension in 2009 and is being amortized over the remaining life of the plant. (e) Deferred charges consist of training related costs, including interest and carrying costs of such training. Amortization will commence effective with the commercial operation date of each unit and amortized to expense over the life of the units. (f) Deferral of premiums paid to purchase interest rate options used to hedge interest rates on certain borrowings, related carrying costs and other incidentals associated with construction of Vogtle Units No. 3 and No. 4. Amortization will commence when Vogtle Unit No. 3 goes in-service, which is expected November 2021. (g) Effects on net margin for Smith and Hawk Road Energy Facilities were deferred through the end of 2015 and are being amortized over the remaining life of each respective plant. (h) Represents the accrual of retirement costs associated with long-lived assets for which there are no legal obligations to retire the assets. (i) Represents collections for future major maintenance costs; revenues are recognized as major maintenance costs are incurred. (j) Represents collections to fund certain debt payments to be made through the end of 2025 which will be in excess of amounts collected through depreciation expense; the deferred credits will be amortized over the remaining useful life of the plants. (k) Represents the difference in the timing of recognition of decommissioning costs for financial statement purposes versus ratemaking purposes, as well as the deferral of unrealized gains and losses of funds set aside for decommissioning. (l) Deferred revenues under a rate management program that allows for additional collections over a five five (m) The amortization periods for other regulatory assets range up to 29 years and the amortization periods of other regulatory liabilities range up to 6 years. |
Fair Value (Tables)
Fair Value (Tables) | 12 Months Ended |
Dec. 31, 2020 | |
Fair Value Disclosures [Abstract] | |
Schedule of assets and liabilities measured at fair value on a recurring basis | Fair Value Measurements at Reporting Date Using December 31, 2020 Quoted Prices in Significant Other Significant (dollars in thousands) Nuclear decommissioning trust funds: Domestic equity $ 198,325 $ 198,325 $ — $ — International equity trust $ 120,645 — 120,645 — Corporate bonds and debt $ 98,129 — 97,788 341 US Treasury securities $ 46,963 46,963 — — Mortgage backed securities $ 45,039 — 45,039 — Domestic mutual funds $ 70,813 70,813 — — Municipal bonds $ 1,362 — 1,362 — Federal agency securities $ 6,054 — 6,054 — Other $ 10,851 7,720 3,131 — Long-term investments: International equity trust $ 31,378 — 31,378 — Corporate bonds and debt $ 29,870 — 29,661 209 US Treasury securities $ 7,437 7,437 — — Mortgage backed securities $ 11,432 — 11,432 — Domestic mutual funds $ 224,536 224,536 — — Federal agency securities $ 537 — 537 — Treasury STRIPS $ 209,165 — 209,165 — Other $ 3,710 3,710 — — Natural gas swaps $ 10,248 — 10,248 — Fair Value Measurements at Reporting Date Using December 31, 2019 Quoted Prices in Significant Other Significant (dollars in thousands) Nuclear decommissioning trust funds: Domestic equity $ 179,346 $ 179,346 $ — $ — International equity trust $ 96,204 — 96,204 — Corporate bonds and debt $ 63,849 — 63,849 — US Treasury securities $ 45,522 45,522 — — Mortgage backed securities $ 62,400 — 62,400 — Domestic mutual funds $ 55,522 55,522 — — Municipal bonds $ 1,189 — 1,189 — Federal agency securities $ 2,586 — 2,586 — Other $ 4,721 4,450 271 — Long-term investments: International equity trust $ 23,161 — 23,161 — Corporate bonds and debt $ 20,395 — 20,395 — US Treasury securities $ 9,257 9,257 — — Mortgage backed securities $ 12,867 — 12,867 — Domestic mutual funds $ 126,380 126,380 — — Federal agency securities $ 1,082 — 1,082 — Treasury STRIPS $ 59,816 — 59,816 — Other $ 1,906 1,906 — — Natural gas swaps $ 32,256 — 32,256 — |
Schedule of estimated fair values of long-term debt, including current maturities | The estimated fair values of our long-term debt, including current maturities at December 31, 2020 and 2019 were as follows: 2020 2019 (in thousands) Carrying Fair Carrying Fair Long-term debt $ 10,619,826 $ 13,161,146 $ 9,726,428 $ 11,180,658 |
Derivative instruments (Tables)
Derivative instruments (Tables) | 12 Months Ended |
Dec. 31, 2020 | |
Derivative Instruments and Hedging Activities Disclosure [Abstract] | |
Schedule of notional volume of natural gas derivatives that is expected to settle or mature each year | The following table reflects the volume activity of our natural gas derivatives as of December 31, 2020 that is expected to settle or mature each year: Year Natural Gas (in millions) 2021 27.5 2022 23.7 2023 18.7 2024 17.5 2025 13.4 Total 100.8 |
Schedule of fair value of derivative instruments and effect on consolidated balance sheets | The table below reflects the fair value of derivative instruments and their effect on our consolidated balance sheets at December 31, 2020 and 2019. Consolidated Balance Sheet Fair Value 2020 2019 (dollars in thousands) Assets Natural gas swaps Other current assets $ 222 $ — Liabilities Natural gas swaps Other current liabilities $ 2,305 $ 12,898 Natural gas swaps Other deferred credits $ 8,165 $ 19,358 |
Schedule of the realized gains and (losses) on derivative instruments recognized in margin | The following table presents the realized gains and (losses) on derivative instruments recognized in margin for the years ended December 31, 2020, 2019 and 2018. Consolidated 2020 2019 2018 (dollars in thousands) Natural Gas Swaps Fuel $ 830 $ 224 $ 6,088 Natural Gas Swaps Fuel (21,179) (9,308) (956) Total $ (20,349) $ (9,084) $ 5,132 |
Schedule of unrealized gains and (losses) on derivative instruments deferred on the balance sheet | The following table presents the unrealized (gains) and losses on derivative instruments deferred on the consolidated balance sheet at December 31, 2020 and 2019. Consolidated Balance 2020 2019 (dollars in thousands) Natural Gas Swaps Regulatory asset $ 10,248 $ 32,256 Total $ 10,248 $ 32,256 |
Investments (Tables)
Investments (Tables) | 12 Months Ended |
Dec. 31, 2020 | |
Schedule of Investments [Abstract] | |
Summary of debt and equity securities | The following tables summarize debt and equity securities at December 31, 2020 and 2019. (dollars in thousands) Gross Unrealized 2020 Cost Gains Losses Fair Value Equity $ 262,564 $ 219,658 $ (8,127) $ 474,095 Debt 613,271 18,090 (641) 630,720 Other 11,431 — — 11,431 Total $ 887,266 $ 237,748 $ (8,768) $ 1,116,246 (dollars in thousands) Gross Unrealized 2019 Cost Gains Losses Fair Value Equity $ 258,870 $ 144,832 $ (5,990) $ 397,712 Debt 354,535 8,474 (874) 362,135 Other 6,356 — — 6,356 Total $ 619,761 $ 153,306 $ (6,864) $ 766,203 |
Schedule of contractual maturities of debt securities | The contractual maturities of debt securities, which are included in the estimated fair value table above, at December 31, 2020 and 2019 are as follows: (dollars in thousands) 2020 2019 Cost Fair Value Cost Fair Value Due within one year $ 163,890 $ 164,635 $ 81,637 $ 81,914 Due after one year through five years 242,958 247,857 47,212 48,188 Due after five years through ten years 68,659 73,479 51,892 54,184 Due after ten years 137,764 144,749 173,794 177,849 Total $ 613,271 $ 630,720 $ 354,535 $ 362,135 |
Summary of realized gains and losses and proceeds from sales of securities | The following table summarizes the realized gains and losses and proceeds from sales of securities for the years ended December 31, 2020, 2019 and 2018: (dollars in thousands) 2020 2019 2018 Gross realized gains $ 36,647 $ 18,076 $ 14,268 Gross realized losses (16,868) (12,018) (19,139) Proceeds from sales 756,513 544,043 626,612 |
Schedule of investments in associated companies | Investments in associated companies were as follows at December 31, 2020 and 2019: (dollars in thousands) 2020 2019 National Rural Utilities Cooperative Finance Corporation (CFC) $ 24,080 $ 24,065 CT Parts, LLC 6,554 7,175 Georgia Transmission Corporation 33,943 32,106 Georgia System Operations Corporation 7,500 7,000 Other 2,767 2,972 Total $ 74,844 $ 73,318 |
Income taxes (Tables)
Income taxes (Tables) | 12 Months Ended |
Dec. 31, 2020 | |
Income Tax Disclosure [Abstract] | |
Summary of difference between statutory federal income tax rate on income before income taxes and effective income tax rate | The difference between the statutory federal income tax rate on income before income taxes and our effective income tax rate is summarized as follows: 2020 2019 2018 Statutory federal income tax rate 21.0 % 21.0 % 21.0 % Patronage exclusion (21.0) % (21.0) % (20.8) % AMT credit monetization 0.0 % 0.0 % 0.0 % Other 0.0 % 0.0 % (0.2) % Effective income tax rate 0.0 % 0.0 % 0.0 % |
Schedule of components of net deferred tax assets and liabilities | The components of our net deferred tax assets and liabilities as of December 31, 2020 and 2019 were as follows: (dollars in thousands) 2020 2019 Deferred tax assets Net operating losses $ — $ 1,123 Tax credits (alternative minimum tax and other) — — Accounting for Rocky Mountain transactions 232,169 231,844 Advance payments 112,394 74,482 Other assets 91,938 88,821 Deferred tax assets 436,501 396,270 Less: Valuation allowance — (1,123) Net deferred tax assets $ 436,501 $ 395,147 Deferred tax liabilities Depreciation $ 254,047 $ 258,724 Accounting for Rocky Mountain transactions 119,773 118,021 Other liabilities 63,797 68,035 Deferred tax liabilities 437,617 444,780 Net deferred tax assets/(liabilities) (1,116) (49,633) Less: Patronage exclusion 1,116 49,633 Net deferred taxes $ — $ — |
Leases (Tables)
Leases (Tables) | 12 Months Ended |
Dec. 31, 2020 | |
Leases [Abstract] | |
Schedule of balance sheet impact of leases | For lease agreements entered into or reassessed after the adoption of the new leases standard, we combine lease and nonlease components. Classification 2020 2019 (dollars in thousands) Right-of-Use Assets - Finance leases Right-of-use assets $ 302,732 $ 302,732 Less: Accumulated provision for depreciation (262,774) (257,504) Total finance lease assets $ 39,958 $ 45,228 Lease liabilities - Finance leases Obligations under finance leases $ 68,876 $ 75,649 Long-term debt and finance leases due within one year 6,773 6,081 Total finance lease liabilities $ 75,649 $ 81,730 Classification 2020 2019 (dollars in thousands) Right-of-Use Assets - Operating leases Electric plant in service $ 3,283 $ 3,237 Total operating lease assets $ 3,283 $ 3,237 Lease liabilities - Operating leases Capitalization - Other $ 2,388 $ 2,293 Other current liabilities 990 1,252 Total operating lease liabilities $ 3,378 $ 3,545 |
Schedule of lease cost | 2020 2019 (dollars in thousands) Lease Cost Classification Finance lease cost: Amortization of leased assets Depreciation and amortization $ 5,376 $ 4,756 Interest on lease liabilities Interest expense $ 8,868 $ 9,488 Operating lease cost Inventory(1) & production expense $ 1,305 $ 3,179 Total lease cost $ 15,549 $ 17,423 (1) The majority of our operating lease costs relate to our railcar leases and such costs are added to the cost of our fossil-fuel inventories and are recognized in fuel expense as the inventories are consumed. |
Summary of lease terms and discount rates | December 31, 2020 December 31, 2019 Lease Term and Discount Rate Weighted-average remaining lease term (in years): Finance leases 7.86 8.84 Operating leases 7.27 7.39 Weighted-average discount rate: Finance leases 11.05 % 11.05 % Operating leases 4.63 % 5.12 % |
Schedule of cash paid for amounts included in the measurement of lease liabilities | 2020 2019 (dollars in thousands) Other Information: Cash paid for amounts included in the measurement of lease liabilities Operating cash flows from finance leases $ 8,868 $ 9,488 Operating cash flows from operating leases $ 1,540 $ 3,710 Financing cash flows from finance leases $ 6,082 $ 5,461 Right-of-use assets obtained in exchange for new operating lease liabilities $ 1,227 $ 6,983 |
Schedule of maturities of finance and operating lease liabilities | Maturity analysis of our finance and operating lease liabilities as of December 31, 2020 is as follows: (dollars in thousands) Year Ending December 31, Finance Leases Operating Leases Total 2021 $ 14,949 $ 1,119 $ 16,068 2022 14,949 929 15,878 2023 14,949 708 15,657 2024 14,949 234 15,183 2025 14,949 72 15,021 Thereafter 40,583 1,012 41,595 Total lease payments $ 115,328 $ 4,074 $ 119,402 Less: imputed interest (39,679) (696) (40,375) Present value of lease liabilities $ 75,649 $ 3,378 $ 79,027 |
Schedule of lessor's income from leases | Lease income recognized during 2020 and 2019 was as follows: 2020 2019 Lease income $ 6,171 $ 6,071 |
Debt (Tables)
Debt (Tables) | 12 Months Ended |
Dec. 31, 2020 | |
Debt Disclosure [Abstract] | |
Schedule of maturities for long-term debt and finance lease obligations | Maturities for long-term debt and finance lease obligations through 2025 are as follows: (dollars in thousands) 2021 2022 2023 2024 2025 FFB $ 200,867 $ 275,553 $ 247,601 $ 222,273 $ 229,168 FMBs 1,010 1,010 1,010 63,510 62,500 PCBs (1) — — 122,620 245,605 — $ 201,877 $ 276,563 $ 371,231 $ 531,388 $ 291,668 Finance Leases 6,772 7,541 8,398 9,351 10,413 Total $ 208,649 $ 284,104 $ 379,629 $ 540,739 $ 302,081 |
Schedule of long-term debt outstanding and the associated unamortized debt issuance costs and debt discounts | Long-term debt outstanding and the associated unamortized debt issuance costs and debt discounts at December 31, 2020 and December 31, 2019 are as follows: 2020 2019 Principal Unamortized Debt Principal Unamortized Debt (dollars in thousands) FFB $ 5,985,015 $ 57,971 $ 5,540,215 $ 60,356 FMBs 3,654,041 49,134 3,205,052 39,793 PCRBs 980,770 12,460 980,770 11,073 CFC — — 391 — $ 10,619,826 $ 119,565 $ 9,726,428 $ 111,222 |
Electric plant, construction _2
Electric plant, construction and related agreements (Tables) | 12 Months Ended |
Dec. 31, 2020 | |
Property, Plant and Equipment [Abstract] | |
Summary of plant investments and related accumulated depreciation | A summary of our plant investments and related accumulated depreciation as of December 31, 2020 and 2019 is as follows: 2020 2019 (dollars in thousands) Plant Investment Accumulated Investment Accumulated In-service (1) Owned property Vogtle Units No. 1 & No. 2 (Nuclear – 30% ownership) $ 3,008,848 $ (1,845,863) $ 2,989,693 $ (1,815,258) Vogtle Units No. 3 & No. 4 (Nuclear – 30% ownership) 57,631 (5,785) 56,991 (4,956) Hatch Units No. 1 & No. 2 (Nuclear – 30% ownership) 952,159 (479,628) 934,567 (462,063) Wansley Units No. 1 & No. 2 (2) (Fossil – 30% ownership) 764,315 (370,177) 749,971 (360,014) Scherer Unit No. 1 (Fossil – 60% ownership) 1,379,513 (569,357) 1,284,508 (545,908) Doyle (Combustion Turbine - 100% ownership) 139,853 (117,005) 137,513 (113,259) Rocky Mountain Units No. 1, No. 2 & No. 3 (Hydro – 75% ownership) 618,965 (281,763) 618,939 (270,058) Hartwell (Combustion Turbine - 100% ownership) 227,154 (113,879) 226,316 (110,008) Hawk Road (Combustion Turbine - 100% ownership) 263,673 (63,907) 260,494 (67,065) Talbot (Combustion Turbine - 100% ownership) 296,398 (152,859) 294,809 (144,847) Chattahoochee (Combined cycle - 100% ownership) 319,234 (160,194) 317,210 (150,805) Smith (Combined cycle - 100% ownership) 672,358 (174,176) 655,106 (195,638) Wansley (Combustion Turbine – 30% ownership) (2) 3,942 (3,847) 3,887 (3,738) Transmission plant 100,344 (60,688) 96,198 (59,096) Other 98,406 (60,904) 96,522 (57,826) Property under capital lease: Scherer Unit No. 2 (Fossil – 60% leasehold) 794,051 (508,262) 789,991 (472,486) Total in-service $ 9,696,844 $ (4,968,294) $ 9,512,715 $ (4,833,025) Construction work in progress Vogtle Units No. 3 & No. 4 $ 5,696,342 $ 4,617,654 Environmental and other 87,237 199,242 Total construction work in progress $ 5,783,579 $ 4,816,896 (1) Amounts include plant acquisition adjustments at December 31, 2020 and 2019 of $197,000,000. (2) Georgia Power is considering retiring Plant Wansley Units No. 1 and No. 2 as early as fall 2022. Although this decision has not been finalized or filed with the Georgia Public Service Commission, we are preparing for a scenario in which a retirement occurs in 2022; including seeking authorization to create a regulatory asset to defer a portion of the accelerated depreciation expense and recover the deferred costs over an extended period. |
Schedule of Jointly Owned Utility Plants | The table below shows our project budget and actual costs through December 31, 2020 for our 30% interest in the project. (in millions) Project Budget Actual Costs at December 31, 2020 Remaining Project Budget Construction Costs (1) $ 5,559 $ 4,754 $ 805 Financing Costs 1,578 1,259 319 Total Costs $ 7,137 $ 6,013 $ 1,124 Project-Level Contingency $ 113 $ — $ 113 Oglethorpe-Level Contingency 250 — 250 Total Contingency $ 363 $ — $ 363 Totals $ 7,500 $ 6,013 $ 1,487 (1) Construction costs are net of $1.1 billion received from Toshiba Corporation under a Guarantee Settlement Agreement. |
Commitments (Tables)
Commitments (Tables) | 12 Months Ended |
Dec. 31, 2020 | |
Commitments and Contingencies Disclosure [Abstract] | |
Schedule of estimated commitments | As of December 31, 2020, our estimated commitments are as follows: (dollars in thousands) Coal Nuclear Fuel Gas Maintenance Asset Finance and Operating Leases 2021 $ 5,168 $ 73,500 $ 63,385 $ 14,429 $ 17,821 $ 16,068 2022 3,017 33,060 53,268 14,896 31,780 15,878 2023 — 17,340 48,707 3,325 34,372 15,657 2024 — 22,650 48,034 30,316 41,840 15,183 2025 — 11,250 46,350 43,212 74,077 15,021 Thereafter — 15,930 746,160 176,751 3,400,140 41,595 |
Quarterly financial data (una_2
Quarterly financial data (unaudited) (Tables) | 12 Months Ended |
Dec. 31, 2020 | |
Quarterly Financial Data [Abstract] | |
Summary of quarterly financial information | Summarized quarterly financial information for 2020 and 2019 is as follows: First Second Third Fourth (dollars in thousands) 2020 Operating revenues $ 341,674 $ 330,944 $ 366,239 $ 338,761 Operating margin 62,515 65,532 47,862 41,800 Net margin 23,204 26,162 8,471 (1,942) 2019 Operating revenues $ 356,600 $ 358,860 $ 382,623 $ 332,209 Operating margin 66,032 51,712 59,209 40,256 Net margin 23,596 9,383 18,286 3,196 |
Summary of significant accoun_4
Summary of significant accounting policies - Business Description (Details) people in Millions | 12 Months Ended |
Dec. 31, 2020peoplememberMW | |
Business description | |
Number of electric distribution cooperative members | member | 38 |
Summer planning reserve capacity of generating units (in megawatts) | 7,125 |
Number of people to whom energy is distributed on a retail basis by the entity's members | people | 4.3 |
Smarr EMC | |
Business description | |
Summer planning reserve capacity of generating units (in megawatts) | 737 |
Green Power EMC | |
Business description | |
Summer planning reserve capacity of generating units (in megawatts) | 320 |
Green Power EMC | Solar energy | |
Business description | |
Summer planning reserve capacity of generating units (in megawatts) | 288 |
Summary of significant accoun_5
Summary of significant accounting policies - Patronage capital and membership fees and Margin policy (Details) | 12 Months Ended | ||
Dec. 31, 2020USD ($) | Dec. 31, 2019 | Dec. 31, 2018 | |
Patronage capital and membership fees | |||
Membership fees | $ 190 | ||
Minimum equity as a percentage of total long-term debt and equities for distributions of patronage capital | 20.00% | ||
Maximum percentage of aggregate net margins in which specified percentage of total long-term debt and equities cannot exceed on or after distributions expended | 35.00% | ||
Minimum equity as a percentage of total long-term debt and equities after distributions of patronage capital | 30.00% | ||
Margin policy | |||
Minimum margins for interest ratio under the first mortgage indenture | 1.10 | 1.10 | 1.10 |
Achieved margins for interest ratio | 1.14 | 1.14 | 1.14 |
Summary of significant accoun_6
Summary of significant accounting policies - Revenue recognition (Details) $ in Thousands | 12 Months Ended | 24 Months Ended | ||
Dec. 31, 2020USD ($)servicemember | Dec. 31, 2019USD ($) | Dec. 31, 2018USD ($) | Dec. 31, 2019USD ($) | |
Revenue Recognition | ||||
Number of electric distribution cooperative members | member | 38 | |||
Number of services provided | service | 2 | |||
Energy supplied to members, percent | 57.00% | 58.00% | 57.00% | |
Minimum margins for interest ratio under the first mortgage indenture | 1.10 | 1.10 | 1.10 | |
Targeted margins for interest ratio | 1.14 | 1.14 | 1.14 | |
Refund liability | $ 32,318 | $ 14,989 | $ 14,989 | |
Total revenues | 1,377,618 | 1,430,292 | $ 1,480,113 | |
Vogtle Units No. 3 & No. 4 | ||||
Operating revenues | ||||
Recovery of financing costs | 14,684 | 14,943 | 12,229 | |
Cumulative recovery of financing costs | $ 95,943 | |||
Additional collection period (in years) | 5 years | |||
Billed amount | $ 125,842 | 73,051 | 15,435 | $ 214,328 |
Members | ||||
Revenue Recognition | ||||
Total revenues | $ 1,377,010 | $ 1,429,852 | $ 1,479,379 | |
Jackson EMC | Total operating revenues | Revenues of members | ||||
Operating revenues | ||||
Concentration risk (as a percent) | 15.20% | 14.40% | 14.10% | |
Cobb EMC | Total operating revenues | Revenues of members | ||||
Operating revenues | ||||
Concentration risk (as a percent) | 13.20% | 13.80% | 13.90% | |
Capacity revenues | Members | ||||
Revenue Recognition | ||||
Total revenues | $ 971,071 | $ 942,057 | $ 927,419 | |
Energy revenues | Members | ||||
Revenue Recognition | ||||
Total revenues | $ 405,939 | $ 487,795 | $ 551,960 |
Summary of significant accoun_7
Summary of significant accounting policies - Receivables (Details) - USD ($) | 12 Months Ended | ||
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | |
Receivables | |||
Impairment losses | $ 0 | $ 0 | $ 0 |
Members | |||
Receivables | |||
Receivables | $ 135,462,000 | $ 142,946,000 | $ 122,888,000 |
Summary of significant accoun_8
Summary of significant accounting policies - Nuclear fuel cost (Details) - USD ($) | 12 Months Ended | ||
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | |
Nuclear fuel cost | |||
Nuclear fuel expense | $ 75,968,000 | $ 79,893,000 | $ 85,949,000 |
Nuclear fuel disposal cost litigation for period from January 1, 2015 through December 31, 2017 | Pending litigation | Plant Hatch and Plant Vogtle | |||
Nuclear fuel cost | |||
Damages receivable | $ 0 | $ 0 |
Summary of significant accoun_9
Summary of significant accounting policies - Asset retirement obligations and other retirement costs (Details) - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | |
Asset retirement obligations | |||
Balance at the beginning of the period | $ 1,070,640 | $ 1,017,563 | |
Liabilities settled | (6,988) | (4,538) | |
Accretion | 54,475 | 50,473 | $ 38,090 |
Deferred accretion | (853) | 1,860 | |
Change in cash flow estimates | 18,709 | 5,282 | |
Balance at the end of the period | 1,135,983 | 1,070,640 | 1,017,563 |
Coal Combustion Residuals | |||
Increase in the obligation for coal ash decommissioning | 10,775 | 5,958 | |
Fund balances for coal ash pond and landfill decommissioning | 120,536 | 93,184 | |
Hatch Unit No. 1 | |||
Nuclear Decommissioning | |||
Estimated costs based on site study | 277,000 | ||
Hatch Unit No. 1 | Radiated structures | |||
Nuclear Decommissioning | |||
Estimated costs based on site study | 209,000 | ||
Hatch Unit No. 1 | Spent fuel management | |||
Nuclear Decommissioning | |||
Estimated costs based on site study | 54,000 | ||
Hatch Unit No. 1 | Non-radiated structures | |||
Nuclear Decommissioning | |||
Estimated costs based on site study | 14,000 | ||
Hatch Unit No. 2 | |||
Nuclear Decommissioning | |||
Estimated costs based on site study | 299,000 | ||
Hatch Unit No. 2 | Radiated structures | |||
Nuclear Decommissioning | |||
Estimated costs based on site study | 231,000 | ||
Hatch Unit No. 2 | Spent fuel management | |||
Nuclear Decommissioning | |||
Estimated costs based on site study | 49,000 | ||
Hatch Unit No. 2 | Non-radiated structures | |||
Nuclear Decommissioning | |||
Estimated costs based on site study | 19,000 | ||
Vogtle Unit No. 1 | |||
Nuclear Decommissioning | |||
Estimated costs based on site study | 266,000 | ||
Vogtle Unit No. 1 | Radiated structures | |||
Nuclear Decommissioning | |||
Estimated costs based on site study | 188,000 | ||
Vogtle Unit No. 1 | Spent fuel management | |||
Nuclear Decommissioning | |||
Estimated costs based on site study | 55,000 | ||
Vogtle Unit No. 1 | Non-radiated structures | |||
Nuclear Decommissioning | |||
Estimated costs based on site study | 23,000 | ||
Vogtle Unit No. 2 | |||
Nuclear Decommissioning | |||
Estimated costs based on site study | 286,000 | ||
Vogtle Unit No. 2 | Radiated structures | |||
Nuclear Decommissioning | |||
Estimated costs based on site study | 206,000 | ||
Vogtle Unit No. 2 | Spent fuel management | |||
Nuclear Decommissioning | |||
Estimated costs based on site study | 51,000 | ||
Vogtle Unit No. 2 | Non-radiated structures | |||
Nuclear Decommissioning | |||
Estimated costs based on site study | 29,000 | ||
Nuclear | |||
Asset retirement obligations | |||
Balance at the beginning of the period | 697,441 | 658,956 | |
Liabilities settled | 0 | 0 | |
Accretion | 40,776 | 38,485 | |
Deferred accretion | 0 | 0 | |
Change in cash flow estimates | 0 | 0 | |
Balance at the end of the period | 738,217 | 697,441 | 658,956 |
Coal Ash Pond | |||
Asset retirement obligations | |||
Balance at the beginning of the period | 329,264 | 326,248 | |
Liabilities settled | (4,656) | (3,380) | |
Accretion | 12,059 | 10,494 | |
Deferred accretion | (853) | 1,860 | |
Change in cash flow estimates | 10,775 | (5,958) | |
Balance at the end of the period | 346,589 | 329,264 | 326,248 |
Other | |||
Asset retirement obligations | |||
Balance at the beginning of the period | 43,935 | 32,359 | |
Liabilities settled | (2,332) | (1,158) | |
Accretion | 1,640 | 1,494 | |
Deferred accretion | 0 | 0 | |
Change in cash flow estimates | 7,934 | 11,240 | |
Balance at the end of the period | $ 51,177 | $ 43,935 | $ 32,359 |
Summary of significant accou_10
Summary of significant accounting policies - Nuclear decommissioning funds (Details) - USD ($) | 12 Months Ended | ||
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | |
Nuclear decommissioning funds | |||
Additional contribution to external trust funds | $ 0 | $ 0 | |
Additional amount collected for nuclear decommissioning | $ 4,750,000 | 4,750,000 | |
Percentage of decommissioning fund classified as equity | 64.00% | ||
Percentage of decommissioning funds classified as fixed income securities | 36.00% | ||
External and Internal Trust Funds: | |||
Purchases | $ 578,610,000 | 374,338,000 | $ 457,909,000 |
Fair Value | $ 598,181,000 | 511,339,000 | |
Average annualized rate of return over the past ten years | 8.40% | ||
Average annualized rate of return since inception | 6.90% | ||
External Trust Funds | |||
External and Internal Trust Funds: | |||
Cost | 386,528,000 | 373,451,000 | |
Purchases | $ 578,610,000 | 374,338,000 | |
Net Proceeds | (555,923,000) | (361,261,000) | |
Unrealized Gain(Loss) | 188,966,000 | 124,811,000 | |
Fair Value | 598,181,000 | 511,339,000 | |
Net realized gains or losses, interest income and dividends, contributions and fees | 22,686,000 | 13,078,000 | |
Internal Funds | |||
External and Internal Trust Funds: | |||
Cost | 91,409,000 | 82,677,000 | |
Purchases | 132,710,000 | 140,997,000 | |
Net Proceeds | (123,004,000) | (132,266,000) | |
Unrealized Gain(Loss) | 36,184,000 | 20,739,000 | |
Fair Value | 137,299,000 | 112,147,000 | |
Net realized gains or losses, interest income and dividends, contributions and fees | 9,705,000 | 8,732,000 | |
Equity | External Trust Funds | |||
External and Internal Trust Funds: | |||
Cost | 212,585,000 | 207,313,000 | |
Purchases | 27,707,000 | 11,950,000 | |
Net Proceeds | (16,444,000) | (6,678,000) | |
Unrealized Gain(Loss) | 177,866,000 | 119,263,000 | |
Fair Value | 401,714,000 | 331,848,000 | |
Equity | Internal Funds | |||
External and Internal Trust Funds: | |||
Cost | 47,062,000 | 44,295,000 | |
Purchases | 0 | 0 | |
Net Proceeds | 3,586,000 | 2,767,000 | |
Unrealized Gain(Loss) | 33,665,000 | 19,578,000 | |
Fair Value | 84,313,000 | 66,640,000 | |
Debt | External Trust Funds | |||
External and Internal Trust Funds: | |||
Cost | 174,645,000 | 166,023,000 | |
Purchases | 536,147,000 | 361,844,000 | |
Net Proceeds | (523,926,000) | (353,222,000) | |
Unrealized Gain(Loss) | 11,100,000 | 5,548,000 | |
Fair Value | 197,966,000 | 180,193,000 | |
Debt | Internal Funds | |||
External and Internal Trust Funds: | |||
Cost | 44,347,000 | 38,382,000 | |
Purchases | 132,710,000 | 140,997,000 | |
Net Proceeds | (126,590,000) | (135,033,000) | |
Unrealized Gain(Loss) | 2,519,000 | 1,161,000 | |
Fair Value | 52,986,000 | 45,507,000 | |
Other | External Trust Funds | |||
External and Internal Trust Funds: | |||
Cost | (702,000) | $ 115,000 | |
Purchases | 14,756,000 | 544,000 | |
Net Proceeds | (15,553,000) | (1,361,000) | |
Unrealized Gain(Loss) | 0 | 0 | |
Fair Value | $ (1,499,000) | $ (702,000) |
Summary of significant accou_11
Summary of significant accounting policies - Depreciation and Electric plant (Details) - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | |
Depreciation | |||
Depreciation expense | $ 242,822 | $ 237,447 | $ 227,213 |
Electric plant | |||
Allowance for funds used during construction (as a percent) | 4.00% | 4.30% | 4.25% |
Steam production | |||
Depreciation | |||
Annual depreciation rates (as a percent) | 2.58% | 2.61% | 2.57% |
Steam production | Minimum | |||
Depreciation | |||
Useful Life | 49 years | 49 years | 49 years |
Steam production | Maximum | |||
Depreciation | |||
Useful Life | 65 years | 65 years | 65 years |
Nuclear production | |||
Depreciation | |||
Annual depreciation rates (as a percent) | 1.93% | 1.94% | 1.92% |
Nuclear production | Minimum | |||
Depreciation | |||
Useful Life | 37 years | 37 years | 37 years |
Nuclear production | Maximum | |||
Depreciation | |||
Useful Life | 60 years | 60 years | 60 years |
Hydro production | |||
Depreciation | |||
Useful Life | 50 years | 50 years | 50 years |
Annual depreciation rates (as a percent) | 2.00% | 2.00% | 2.00% |
Other production | |||
Depreciation | |||
Annual depreciation rates (as a percent) | 2.61% | 2.61% | 2.61% |
Other production | Minimum | |||
Depreciation | |||
Useful Life | 30 years | 30 years | 30 years |
Other production | Maximum | |||
Depreciation | |||
Useful Life | 35 years | 35 years | 35 years |
Transmission | |||
Depreciation | |||
Useful Life | 36 years | 36 years | 36 years |
Annual depreciation rates (as a percent) | 2.75% | 2.75% | 2.75% |
General | Minimum | |||
Depreciation | |||
Useful Life | 3 years | 3 years | 3 years |
Annual depreciation rates (as a percent) | 2.00% | 2.00% | 2.00% |
General | Maximum | |||
Depreciation | |||
Useful Life | 50 years | 50 years | 50 years |
Annual depreciation rates (as a percent) | 33.33% | 33.33% | 33.33% |
Summary of significant accou_12
Summary of significant accounting policies - Restricted investments and Inventories (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Oct. 01, 2020 | Sep. 30, 2020 | Dec. 31, 2019 |
Restricted investments | ||||
Investment interest rate | 4.00% | 5.00% | ||
Restricted investments | $ 487,587 | $ 533,590 | ||
Restricted investments, long-term | 306,601 | 461,757 | ||
Inventories | ||||
Fossil fuels inventories | 83,547 | 74,257 | ||
Spare parts | $ 196,742 | $ 203,472 |
Summary of significant accou_13
Summary of significant accounting policies - Regulatory assets and liabilities (Details) - USD ($) $ in Thousands | 12 Months Ended | |
Dec. 31, 2020 | Dec. 31, 2019 | |
Regulatory Assets and Liabilities | ||
Total Regulatory Assets | $ 731,438 | $ 763,512 |
Total Regulatory Liabilities | 566,399 | 364,241 |
Net Regulatory Assets | 165,039 | 399,271 |
Accumulated retirement costs for other obligations | ||
Regulatory Assets and Liabilities | ||
Total Regulatory Liabilities | 20,054 | 12,692 |
Deferral of effects on net margin | Hawk Road Energy Facility | ||
Regulatory Assets and Liabilities | ||
Total Regulatory Liabilities | 17,869 | 18,485 |
Major maintenance reserve | ||
Regulatory Assets and Liabilities | ||
Total Regulatory Liabilities | 39,776 | 50,144 |
Amortization on capital leases | ||
Regulatory Assets and Liabilities | ||
Total Regulatory Liabilities | 11,356 | 14,256 |
Deferred debt service adder | ||
Regulatory Assets and Liabilities | ||
Total Regulatory Liabilities | 123,772 | 114,453 |
Nuclear | ||
Regulatory Assets and Liabilities | ||
Total Regulatory Liabilities | 130,901 | 61,516 |
Revenue deferral plan | ||
Regulatory Assets and Liabilities | ||
Total Regulatory Liabilities | $ 220,111 | 90,066 |
Amortization period, other regulatory liabilities | 5 years | |
Other regulatory liabilities | ||
Regulatory Assets and Liabilities | ||
Total Regulatory Liabilities | $ 2,560 | 2,629 |
Other regulatory liabilities | Maximum | ||
Regulatory Assets and Liabilities | ||
Amortization period, other regulatory liabilities | 6 years | |
Premium and loss on reacquired debt | ||
Regulatory Assets and Liabilities | ||
Total Regulatory Assets | $ 35,433 | 40,067 |
Premium and loss on reacquired debt | Maximum | ||
Regulatory Assets and Liabilities | ||
Amortization period, other regulatory assets | 23 years | |
Amortization on financing leases | ||
Regulatory Assets and Liabilities | ||
Total Regulatory Assets | $ 35,328 | 35,433 |
Outage costs | ||
Regulatory Assets and Liabilities | ||
Total Regulatory Assets | $ 35,232 | 34,367 |
Coal-fired maintenance outage costs | Maximum | ||
Regulatory Assets and Liabilities | ||
Amortization period, other regulatory assets | 60 months | |
Nuclear refueling outage costs | Minimum | ||
Regulatory Assets and Liabilities | ||
Amortization period, other regulatory assets | 18 months | |
Nuclear refueling outage costs | Maximum | ||
Regulatory Assets and Liabilities | ||
Amortization period, other regulatory assets | 24 months | |
Asset retirement obligations - Ashpond and other | ||
Regulatory Assets and Liabilities | ||
Total Regulatory Assets | $ 242,832 | 245,932 |
Depreciation expense | ||
Regulatory Assets and Liabilities | ||
Total Regulatory Assets | $ 38,396 | 39,820 |
Depreciation expense | Plant Vogtle | ||
Regulatory Assets and Liabilities | ||
Operating license expected extension period for Plant Vogtle | 20 years | |
Operating license period | 40 years | |
Deferred charges related to Vogtle Units No. 3 and No. 4 training costs | Vogtle Units No. 3 & No. 4 | ||
Regulatory Assets and Liabilities | ||
Total Regulatory Assets | $ 55,430 | 53,466 |
Interest rate options cost | ||
Regulatory Assets and Liabilities | ||
Total Regulatory Assets | 126,813 | 121,938 |
Deferral of effects on net margin | Smith Energy Facility | ||
Regulatory Assets and Liabilities | ||
Total Regulatory Assets | 148,620 | 154,564 |
Other regulatory assets | ||
Regulatory Assets and Liabilities | ||
Total Regulatory Assets | $ 13,354 | $ 37,925 |
Other regulatory assets | Maximum | ||
Regulatory Assets and Liabilities | ||
Amortization period, other regulatory assets | 29 years |
Summary of significant accou_14
Summary of significant accounting policies - Related parties (Details) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2020USD ($)member | Dec. 31, 2019USD ($) | Dec. 31, 2018USD ($) | |
Related parties | |||
Number of electric distribution cooperative members | 38 | ||
Georgia Transmission Corporation | |||
Related parties | |||
Number of electric distribution cooperative members | 38 | ||
Expenses incurred for transmission services, system operations services and administrative support services | $ | $ 37,931 | $ 37,156 | $ 30,428 |
Georgia System Operations Corporation | |||
Related parties | |||
Number of electric distribution cooperative members | 38 | ||
Expenses incurred for transmission services, system operations services and administrative support services | $ | $ 27,104 | $ 26,730 | $ 25,578 |
Fair Value - Asset and liabilit
Fair Value - Asset and liabilities measured at fair value on a recurring basis (Details) - USD ($) $ in Thousands | 12 Months Ended | |
Dec. 31, 2020 | Dec. 31, 2019 | |
Fair value | ||
Nuclear decommissioning trust fund | $ 598,181 | $ 511,339 |
Long-term investments | 518,065 | 254,864 |
Natural gas swaps | ||
Fair value | ||
Derivative liabilities | 10,248 | 32,256 |
International equity trust | ||
Fair value | ||
Unfunded commitments | $ 0 | |
Redemption notice period | 3 days | |
Recurring basis | Natural gas swaps | ||
Fair value | ||
Derivative liabilities | $ 10,248 | 32,256 |
Recurring basis | Domestic equity | ||
Fair value | ||
Nuclear decommissioning trust fund | 198,325 | 179,346 |
Recurring basis | International equity trust | ||
Fair value | ||
Nuclear decommissioning trust fund | 120,645 | 96,204 |
Long-term investments | 31,378 | 23,161 |
Recurring basis | Corporate bonds and debt | ||
Fair value | ||
Nuclear decommissioning trust fund | 98,129 | 63,849 |
Long-term investments | 29,870 | 20,395 |
Recurring basis | US Treasury securities | ||
Fair value | ||
Nuclear decommissioning trust fund | 46,963 | 45,522 |
Long-term investments | 7,437 | 9,257 |
Recurring basis | Mortgage backed securities | ||
Fair value | ||
Nuclear decommissioning trust fund | 45,039 | 62,400 |
Long-term investments | 11,432 | 12,867 |
Recurring basis | Domestic mutual funds | ||
Fair value | ||
Nuclear decommissioning trust fund | 70,813 | 55,522 |
Long-term investments | 224,536 | 126,380 |
Recurring basis | Municipal bonds | ||
Fair value | ||
Nuclear decommissioning trust fund | 1,362 | 1,189 |
Recurring basis | Federal agency securities | ||
Fair value | ||
Nuclear decommissioning trust fund | 6,054 | 2,586 |
Long-term investments | 537 | 1,082 |
Recurring basis | Treasury STRIPS | ||
Fair value | ||
Long-term investments | 209,165 | 59,816 |
Recurring basis | Other | ||
Fair value | ||
Nuclear decommissioning trust fund | 10,851 | 4,721 |
Long-term investments | 3,710 | 1,906 |
Recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Natural gas swaps | ||
Fair value | ||
Derivative liabilities | 0 | 0 |
Recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Domestic equity | ||
Fair value | ||
Nuclear decommissioning trust fund | 198,325 | 179,346 |
Recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | International equity trust | ||
Fair value | ||
Nuclear decommissioning trust fund | 0 | 0 |
Long-term investments | 0 | 0 |
Recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Corporate bonds and debt | ||
Fair value | ||
Nuclear decommissioning trust fund | 0 | 0 |
Long-term investments | 0 | 0 |
Recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | US Treasury securities | ||
Fair value | ||
Nuclear decommissioning trust fund | 46,963 | 45,522 |
Long-term investments | 7,437 | 9,257 |
Recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Mortgage backed securities | ||
Fair value | ||
Nuclear decommissioning trust fund | 0 | 0 |
Long-term investments | 0 | 0 |
Recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Domestic mutual funds | ||
Fair value | ||
Nuclear decommissioning trust fund | 70,813 | 55,522 |
Long-term investments | 224,536 | 126,380 |
Recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Municipal bonds | ||
Fair value | ||
Nuclear decommissioning trust fund | 0 | 0 |
Recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Federal agency securities | ||
Fair value | ||
Nuclear decommissioning trust fund | 0 | 0 |
Long-term investments | 0 | 0 |
Recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Treasury STRIPS | ||
Fair value | ||
Long-term investments | 0 | 0 |
Recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other | ||
Fair value | ||
Nuclear decommissioning trust fund | 7,720 | 4,450 |
Long-term investments | 3,710 | 1,906 |
Recurring basis | Significant Other Observable Inputs (Level 2) | Natural gas swaps | ||
Fair value | ||
Derivative liabilities | 10,248 | 32,256 |
Recurring basis | Significant Other Observable Inputs (Level 2) | Domestic equity | ||
Fair value | ||
Nuclear decommissioning trust fund | 0 | 0 |
Recurring basis | Significant Other Observable Inputs (Level 2) | International equity trust | ||
Fair value | ||
Nuclear decommissioning trust fund | 120,645 | 96,204 |
Long-term investments | 31,378 | 23,161 |
Recurring basis | Significant Other Observable Inputs (Level 2) | Corporate bonds and debt | ||
Fair value | ||
Nuclear decommissioning trust fund | 97,788 | 63,849 |
Long-term investments | 29,661 | 20,395 |
Recurring basis | Significant Other Observable Inputs (Level 2) | US Treasury securities | ||
Fair value | ||
Nuclear decommissioning trust fund | 0 | 0 |
Long-term investments | 0 | 0 |
Recurring basis | Significant Other Observable Inputs (Level 2) | Mortgage backed securities | ||
Fair value | ||
Nuclear decommissioning trust fund | 45,039 | 62,400 |
Long-term investments | 11,432 | 12,867 |
Recurring basis | Significant Other Observable Inputs (Level 2) | Domestic mutual funds | ||
Fair value | ||
Nuclear decommissioning trust fund | 0 | 0 |
Long-term investments | 0 | 0 |
Recurring basis | Significant Other Observable Inputs (Level 2) | Municipal bonds | ||
Fair value | ||
Nuclear decommissioning trust fund | 1,362 | 1,189 |
Recurring basis | Significant Other Observable Inputs (Level 2) | Federal agency securities | ||
Fair value | ||
Nuclear decommissioning trust fund | 6,054 | 2,586 |
Long-term investments | 537 | 1,082 |
Recurring basis | Significant Other Observable Inputs (Level 2) | Treasury STRIPS | ||
Fair value | ||
Long-term investments | 209,165 | 59,816 |
Recurring basis | Significant Other Observable Inputs (Level 2) | Other | ||
Fair value | ||
Nuclear decommissioning trust fund | 3,131 | 271 |
Long-term investments | 0 | 0 |
Recurring basis | Significant Unobservable Inputs (Level 3) | Natural gas swaps | ||
Fair value | ||
Derivative liabilities | 0 | 0 |
Recurring basis | Significant Unobservable Inputs (Level 3) | Domestic equity | ||
Fair value | ||
Nuclear decommissioning trust fund | 0 | 0 |
Recurring basis | Significant Unobservable Inputs (Level 3) | International equity trust | ||
Fair value | ||
Nuclear decommissioning trust fund | 0 | 0 |
Long-term investments | 0 | 0 |
Recurring basis | Significant Unobservable Inputs (Level 3) | Corporate bonds and debt | ||
Fair value | ||
Nuclear decommissioning trust fund | 341 | 0 |
Long-term investments | 209 | 0 |
Recurring basis | Significant Unobservable Inputs (Level 3) | US Treasury securities | ||
Fair value | ||
Nuclear decommissioning trust fund | 0 | 0 |
Long-term investments | 0 | 0 |
Recurring basis | Significant Unobservable Inputs (Level 3) | Mortgage backed securities | ||
Fair value | ||
Nuclear decommissioning trust fund | 0 | 0 |
Long-term investments | 0 | 0 |
Recurring basis | Significant Unobservable Inputs (Level 3) | Domestic mutual funds | ||
Fair value | ||
Nuclear decommissioning trust fund | 0 | 0 |
Long-term investments | 0 | 0 |
Recurring basis | Significant Unobservable Inputs (Level 3) | Municipal bonds | ||
Fair value | ||
Nuclear decommissioning trust fund | 0 | 0 |
Recurring basis | Significant Unobservable Inputs (Level 3) | Federal agency securities | ||
Fair value | ||
Nuclear decommissioning trust fund | 0 | 0 |
Long-term investments | 0 | 0 |
Recurring basis | Significant Unobservable Inputs (Level 3) | Treasury STRIPS | ||
Fair value | ||
Long-term investments | 0 | 0 |
Recurring basis | Significant Unobservable Inputs (Level 3) | Other | ||
Fair value | ||
Nuclear decommissioning trust fund | 0 | 0 |
Long-term investments | $ 0 | $ 0 |
Fair Value - Estimated fair val
Fair Value - Estimated fair value of long-term debt (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019 |
Carrying Value | ||
Fair Value | ||
Long-term debt | $ 10,619,826 | $ 9,726,428 |
Fair Value | Significant Other Observable Inputs (Level 2) | ||
Fair Value | ||
Long-term debt | $ 13,161,146 | $ 11,180,658 |
Derivative Instruments - Gas he
Derivative Instruments - Gas hedges (Details) - Natural gas swaps $ in Thousands, MMBTU in Millions | 12 Months Ended | |
Dec. 31, 2020USD ($)MMBTU | Dec. 31, 2019USD ($) | |
Derivative Instruments | ||
Derivative liabilities | $ | $ 10,248 | $ 32,256 |
Letters of credit | $ | $ 10,248 | |
Notional volume of natural gas derivatives (in MMBTUs) | 100.8 | |
2021 | ||
Derivative Instruments | ||
Notional volume of natural gas derivatives (in MMBTUs) | 27.5 | |
2022 | ||
Derivative Instruments | ||
Notional volume of natural gas derivatives (in MMBTUs) | 23.7 | |
2023 | ||
Derivative Instruments | ||
Notional volume of natural gas derivatives (in MMBTUs) | 18.7 | |
2024 | ||
Derivative Instruments | ||
Notional volume of natural gas derivatives (in MMBTUs) | 17.5 | |
2025 | ||
Derivative Instruments | ||
Notional volume of natural gas derivatives (in MMBTUs) | 13.4 |
Derivative Instruments - Fair v
Derivative Instruments - Fair value of derivative instruments not designated as hedging (Details) - Natural gas swaps - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019 |
Liabilities: | ||
Liabilities | $ 10,248 | $ 32,256 |
Not designated as hedges | Other current assets | ||
Assets: | ||
Assets | 222 | 0 |
Not designated as hedges | Other current liabilities | ||
Liabilities: | ||
Liabilities | 2,305 | 12,898 |
Not designated as hedges | Other deferred credits | ||
Liabilities: | ||
Liabilities | $ 8,165 | $ 19,358 |
Derivative Instruments - Realiz
Derivative Instruments - Realized and unrealized gains and (losses) on derivative instruments (Details) - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | |
Gains and (losses) on derivative instruments | |||
Net unrealized losses on derivative instruments | $ 10,248 | $ 32,256 | |
Natural gas swaps | Regulatory asset | |||
Gains and (losses) on derivative instruments | |||
Net unrealized losses on derivative instruments | 10,248 | 32,256 | |
Natural gas swaps | Fuel | |||
Gains and (losses) on derivative instruments | |||
Gains | 830 | 224 | $ 6,088 |
Losses | (21,179) | (9,308) | (956) |
Total | $ (20,349) | $ (9,084) | $ 5,132 |
Investments - Investments in De
Investments - Investments in Debt and Equity Securities (Details) - USD ($) $ in Thousands | 12 Months Ended | |
Dec. 31, 2020 | Dec. 31, 2019 | |
Cost | ||
Equity | $ 262,564 | $ 258,870 |
Debt | 613,271 | 354,535 |
Other | 11,431 | 6,356 |
Total | 887,266 | 619,761 |
Gross Unrealized Gains | ||
Equity | 219,658 | 144,832 |
Debt | 18,090 | 8,474 |
Other | 0 | 0 |
Total | 237,748 | 153,306 |
Gross Unrealized Losses | ||
Equity | (8,127) | (5,990) |
Debt | (641) | (874) |
Other | 0 | 0 |
Total | (8,768) | (6,864) |
Fair Value | ||
Equity | 474,095 | 397,712 |
Debt | 630,720 | 362,135 |
Other | 11,431 | 6,356 |
Total | $ 1,116,246 | $ 766,203 |
Investments - Contractual Matur
Investments - Contractual Maturities of Debt Securities (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019 |
Cost | ||
Due within one year | $ 163,890 | $ 81,637 |
Due after one year through five years | 242,958 | 47,212 |
Due after five years through ten years | 68,659 | 51,892 |
Due after ten years | 137,764 | 173,794 |
Total | 613,271 | 354,535 |
Fair Value | ||
Due within one year | 164,635 | 81,914 |
Due after one year through five years | 247,857 | 48,188 |
Due after five years through ten years | 73,479 | 54,184 |
Due after ten years | 144,749 | 177,849 |
Total | $ 630,720 | $ 362,135 |
Investments - Gross realized ga
Investments - Gross realized gains, losses and proceeds from sales of securities (Details) - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | |
Schedule of Investments [Abstract] | |||
Gross realized gains | $ 36,647 | $ 18,076 | $ 14,268 |
Gross realized losses | (16,868) | (12,018) | (19,139) |
Proceeds from sales | $ 756,513 | $ 544,043 | $ 626,612 |
Investments - Investment in ass
Investments - Investment in associated companies (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019 |
Investment in associated companies | ||
Investment in associated companies | $ 74,844 | $ 73,318 |
National Rural Utilities Cooperative Finance Corporation (CFC) | ||
Investment in associated companies | ||
Investment in associated companies | 24,080 | 24,065 |
CT Parts, LLC | ||
Investment in associated companies | ||
Investment in associated companies | 6,554 | 7,175 |
Georgia Transmission Corporation | ||
Investment in associated companies | ||
Investment in associated companies | 33,943 | 32,106 |
Georgia System Operations Corporation | ||
Investment in associated companies | ||
Investment in associated companies | 7,500 | 7,000 |
Other | ||
Investment in associated companies | ||
Investment in associated companies | $ 2,767 | $ 2,972 |
Investments - Rocky Mountain tr
Investments - Rocky Mountain transactions (Details) - Rocky Mountain $ in Thousands | 2 Months Ended | 12 Months Ended | |
Jan. 31, 1997investorleasetrust | Dec. 31, 2013lease | Dec. 31, 2012USD ($)installmentlease | |
Rocky Mountain transactions | |||
Number of long-term lease transactions | lease | 6 | 6 | |
Percentage of undivided ownership interest | 74.61% | ||
Number of separate owner trusts to whom undivided interest was leased | trust | 6 | ||
Number of investors in ownership trusts | investor | 3 | ||
Term of lease as a percentage of the estimated useful life of the jointly owned utility plant | 120.00% | ||
Term of lease | 30 years | ||
Number of leases terminated prior to end of lease term | lease | 5 | ||
Percentage of leases which remained in place | 10.00% | ||
Basic rental payments due | $ 30,892 | ||
Purchase option price | 112,000 | ||
Outstanding loan amount | $ 74,000 | ||
Percentage to be purchased under first option if financing cannot be arranged | 49.00% | ||
Maximum | |||
Rocky Mountain transactions | |||
Additional term of sublease | 16 years | ||
AIG Matched Funding Corp | |||
Rocky Mountain transactions | |||
Fund amount under payment undertaking agreement | $ 74,000 | ||
Fund amount under equity funding agreement | $ 37,928 | ||
Number of installments available to pay to the owner trust | installment | 5 |
Income taxes - Statutory federa
Income taxes - Statutory federal and effective income tax rate and components of deferred tax assets and liabilities (Details) - USD ($) | 12 Months Ended | ||
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | |
Income Tax Disclosure [Abstract] | |||
Current period income tax expense | $ 0 | ||
Current income tax liability | $ 0 | ||
Difference between statutory federal income tax rate on income before income taxes and effective income tax rate | |||
Statutory federal income tax rate | 21.00% | 21.00% | 21.00% |
Patronage exclusion | (21.00%) | (21.00%) | (20.80%) |
AMT credit monetization | 0.00% | 0.00% | 0.00% |
Other | 0.00% | 0.00% | (0.20%) |
Effective income tax rate | 0.00% | 0.00% | 0.00% |
Deferred tax assets | |||
Net operating losses | $ 0 | $ 1,123,000 | |
Tax credits (alternative minimum tax and other) | 0 | 0 | |
Accounting for Rocky Mountain transactions | 232,169,000 | 231,844,000 | |
Advance payments | 112,394,000 | 74,482,000 | |
Other assets | 91,938,000 | 88,821,000 | |
Deferred tax assets | 436,501,000 | 396,270,000 | |
Less: Valuation allowance | 0 | (1,123,000) | |
Net deferred tax assets | 436,501,000 | 395,147,000 | |
Deferred tax liabilities | |||
Depreciation | 254,047,000 | 258,724,000 | |
Accounting for Rocky Mountain transactions | 119,773,000 | 118,021,000 | |
Other liabilities | 63,797,000 | 68,035,000 | |
Deferred tax liabilities | 437,617,000 | 444,780,000 | |
Net deferred tax assets/(liabilities) | (1,116,000) | (49,633,000) | |
Less: Patronage exclusion | 1,116,000 | 49,633,000 | |
Net deferred taxes | $ 0 | $ 0 |
Income taxes - NOLs and alterna
Income taxes - NOLs and alternative minimum tax credits (Details) $ in Thousands | Dec. 31, 2020USD ($) |
2020 | |
Income taxes | |
Net operating loss carryforwards | $ 4,362 |
Leases - Summary (Details)
Leases - Summary (Details) | 12 Months Ended |
Dec. 31, 2020lease | |
Minimum | |
Lease Disclosure [Line Items] | |
Finance lease, renewal term | 1 year |
Maximum | |
Lease Disclosure [Line Items] | |
Finance lease, renewal term | 5 years |
Lease terms through December 31, 2027 | |
Lease Disclosure [Line Items] | |
Number of finance leases | 3 |
Lease terms through June 30, 2031 | |
Lease Disclosure [Line Items] | |
Number of finance leases | 1 |
Lease terms through February 2024 | |
Lease Disclosure [Line Items] | |
Operating lease, renewal term | 20 years |
Scherer Unit No. 2 | |
Lease Disclosure [Line Items] | |
Percentage of undivided interest | 60.00% |
Leases - Balance Sheet Impact (
Leases - Balance Sheet Impact (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019 |
Right-of-Use Assets - Finance leases | ||
Right-of-use assets | $ 302,732 | $ 302,732 |
Less: Accumulated provision for depreciation | (262,774) | (257,504) |
Total finance lease assets | 39,958 | 45,228 |
Lease liabilities - Finance leases | ||
Obligations under finance leases | 68,876 | 75,649 |
Long-term debt and finance leases due within one year | 6,773 | 6,081 |
Total finance lease liabilities | 75,649 | 81,730 |
Right-of-Use Assets - Operating leases | ||
Electric plant in service | 3,283 | 3,237 |
Total operating lease assets | 3,283 | 3,237 |
Lease liabilities - Operating leases | ||
Capitalization - Other | 2,388 | 2,293 |
Other current liabilities | 990 | 1,252 |
Total operating lease liabilities | $ 3,378 | $ 3,545 |
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List] | us-gaap:OtherLiabilitiesCurrent | us-gaap:OtherLiabilitiesCurrent |
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List] | opc:ObligationUnderHydroFacilityTransactions | opc:ObligationUnderHydroFacilityTransactions |
Leases - Lease Cost (Details)
Leases - Lease Cost (Details) - USD ($) $ in Thousands | 12 Months Ended | |
Dec. 31, 2020 | Dec. 31, 2019 | |
Lease Cost | ||
Amortization of leased assets | $ 5,376 | $ 4,756 |
Interest on lease liabilities | 8,868 | 9,488 |
Operating lease cost | 1,305 | 3,179 |
Total lease cost | $ 15,549 | $ 17,423 |
Weighted-average remaining lease term | ||
Finance leases | 7 years 10 months 9 days | 8 years 10 months 2 days |
Operating leases | 7 years 3 months 7 days | 7 years 4 months 20 days |
Weighted-average discount rate: | ||
Finance leases | 11.05% | 11.05% |
Operating leases | 4.63% | 5.12% |
Leases - Other Lease Disclosure
Leases - Other Lease Disclosures (Details) - USD ($) $ in Thousands | 12 Months Ended | |
Dec. 31, 2020 | Dec. 31, 2019 | |
Lessee Disclosure [Abstract] | ||
Operating cash flows from finance leases | $ 8,868 | $ 9,488 |
Operating cash flows from operating leases | 1,540 | 3,710 |
Financing cash flows from finance leases | 6,082 | 5,461 |
Right-of-use assets obtained in exchange for new operating lease liabilities | 1,227 | 6,983 |
Finance Leases | ||
2021 | 14,949 | |
2022 | 14,949 | |
2023 | 14,949 | |
2024 | 14,949 | |
2025 | 14,949 | |
Thereafter | 40,583 | |
Total lease payments | 115,328 | |
Less: imputed interest | (39,679) | |
Total finance lease liabilities | 75,649 | 81,730 |
Operating Leases | ||
2021 | 1,119 | |
2022 | 929 | |
2023 | 708 | |
2024 | 234 | |
2025 | 72 | |
Thereafter | 1,012 | |
Total lease payments | 4,074 | |
Less: imputed interest | (696) | |
Total operating lease liabilities | 3,378 | 3,545 |
Total | ||
2021 | 16,068 | |
2022 | 15,878 | |
2023 | 15,657 | |
2024 | 15,183 | |
2025 | 15,021 | |
Thereafter | 41,595 | |
Total lease payments | 119,402 | |
Less: imputed interest | (40,375) | |
Present value of lease liabilities | 79,027 | |
Lessor Disclosure [Abstract] | ||
Lease income | $ 6,171 | $ 6,071 |
Debt - Maturities for long-term
Debt - Maturities for long-term debt and finance lease obligations and debt outstanding (Details) - USD ($) | Dec. 31, 2020 | Dec. 31, 2019 |
Maturities for long-term debt and capital lease obligations | ||
2021 | $ 208,649,000 | |
2022 | 284,104,000 | |
2023 | 379,629,000 | |
2024 | 540,739,000 | |
2025 | 302,081,000 | |
Long-term debt outstanding and the associated unamortized debt issuance costs and debt discounts | ||
Principal | 10,619,826,000 | $ 9,726,428,000 |
Long-term debt | ||
Maturities for long-term debt and capital lease obligations | ||
2021 | 201,877,000 | |
2022 | 276,563,000 | |
2023 | 371,231,000 | |
2024 | 531,388,000 | |
2025 | $ 291,668,000 | |
Weighted average interest rate on long-term debt | 3.73% | 3.96% |
Long-term debt outstanding and the associated unamortized debt issuance costs and debt discounts | ||
Principal | $ 10,619,826,000 | $ 9,726,428,000 |
Unamortized Debt Issuance Costs and Debt Discounts | 119,565,000 | 111,222,000 |
Finance Leases | ||
Maturities for long-term debt and capital lease obligations | ||
2021 | 6,772,000 | |
2022 | 7,541,000 | |
2023 | 8,398,000 | |
2024 | 9,351,000 | |
2025 | 10,413,000 | |
Credit Facility | ||
Maturities for long-term debt and capital lease obligations | ||
Principal amount | 1,210,000,000 | |
FFB | Long-term debt | ||
Maturities for long-term debt and capital lease obligations | ||
2021 | 200,867,000 | |
2022 | 275,553,000 | |
2023 | 247,601,000 | |
2024 | 222,273,000 | |
2025 | 229,168,000 | |
Long-term debt outstanding and the associated unamortized debt issuance costs and debt discounts | ||
Principal | 5,985,015,000 | 5,540,215,000 |
Unamortized Debt Issuance Costs and Debt Discounts | 57,971,000 | 60,356,000 |
FMBs | Long-term debt | ||
Maturities for long-term debt and capital lease obligations | ||
2021 | 1,010,000 | |
2022 | 1,010,000 | |
2023 | 1,010,000 | |
2024 | 63,510,000 | |
2025 | 62,500,000 | |
Long-term debt outstanding and the associated unamortized debt issuance costs and debt discounts | ||
Principal | 3,654,041,000 | 3,205,052,000 |
Unamortized Debt Issuance Costs and Debt Discounts | 49,134,000 | 39,793,000 |
PCBs | Long-term debt | ||
Maturities for long-term debt and capital lease obligations | ||
2021 | 0 | |
2022 | 0 | |
2023 | 122,620,000 | |
2024 | 245,605,000 | |
2025 | 0 | |
Principal amount | 245,600,000 | |
Long-term debt outstanding and the associated unamortized debt issuance costs and debt discounts | ||
Principal | 980,770,000 | 980,770,000 |
Unamortized Debt Issuance Costs and Debt Discounts | 12,460,000 | 11,073,000 |
Series 2017 bonds | Long-term debt | ||
Maturities for long-term debt and capital lease obligations | ||
2023 | 122,600,000 | |
CFC | Long-term debt | ||
Long-term debt outstanding and the associated unamortized debt issuance costs and debt discounts | ||
Principal | 0 | 391,000 |
Unamortized Debt Issuance Costs and Debt Discounts | $ 0 | $ 0 |
Debt - Department of Energy Loa
Debt - Department of Energy Loan Guarantee (Details) | 12 Months Ended | |||||
Dec. 31, 2020USD ($) | Dec. 31, 2019USD ($) | Dec. 31, 2018USD ($) | Mar. 22, 2019USD ($) | Dec. 31, 2017USD ($) | Feb. 20, 2014USD ($)note | |
Debt | ||||||
Repayments of long-term debt | $ 1,334,368,000 | $ 523,691,000 | $ 201,354,000 | |||
Vogtle Units No. 3 & No. 4 | ||||||
Debt | ||||||
Guarantee obligations, maximum exposure received | $ 1,104,000,000 | |||||
Long-term debt | ||||||
Debt | ||||||
Ownership interests voting required to continue construction (as a percent) | 90.00% | |||||
Long-term debt | Department of Energy guarantee | ||||||
Debt | ||||||
Aggregate borrowings including capitalized interest | $ 3,633,348,382 | |||||
Long-term debt | FFB | ||||||
Debt | ||||||
Number of future advance promissory notes | note | 2 | |||||
Maximum borrowing capacity | $ 1,619,679,706 | $ 3,057,069,461 | ||||
Aggregate borrowings including capitalized interest | 620,000,000 | |||||
Maximum borrowing capacity designated for capitalized interest | 43,721,079 | 335,471,604 | ||||
Eligible project costs, percent | 70.00% | |||||
Repayments of long-term debt | $ 79,100,000 | |||||
Long-term debt | FFB | Vogtle Units No. 3 & No. 4 | ||||||
Debt | ||||||
Term of debt | 5 years | |||||
Period of cessation of construction activities which would result in prepayment of outstanding principal | 12 months | |||||
Period of failure to fund operation and maintenance expenses which would result in prepayment of outstanding principal | 12 months | |||||
Long-term debt | FFB | Maximum | ||||||
Debt | ||||||
Aggregate borrowings including capitalized interest | $ 3,057,069,461 | |||||
Long-term debt | FFB | Department of Energy guarantee | Services Agreement | ||||||
Debt | ||||||
Guarantee obligations, maximum exposure received | $ 4,676,749,167 | |||||
Long-term debt | FFB | US Treasury Securities, Current Yield | ||||||
Debt | ||||||
Spread on variable rate (as a percent) | 0.375% |
Debt - Rural Utilities Service
Debt - Rural Utilities Service Guaranteed Loans (Details) - Long-term debt - FFB - Rural Utilities Service Guaranteed Loans - USD ($) $ in Thousands | 1 Months Ended | 12 Months Ended |
Jan. 31, 2021 | Dec. 31, 2020 | |
Debt | ||
Advances received on loans | $ 45,925 | |
Subsequent Event | ||
Debt | ||
Advances received on loans | $ 238,578 |
Debt - Credit Facilities (Detai
Debt - Credit Facilities (Details) | Mar. 31, 2020USD ($) | Dec. 31, 2020USD ($)facility | Mar. 27, 2020USD ($) | Mar. 26, 2020USD ($) |
Debt | ||||
Payments to Acquire Investments to be Held in Bond Purchase Fund | $ 212,760,000 | |||
Line of credit | ||||
Debt | ||||
Maximum borrowing capacity | $ 1,200,000,000 | |||
JPMorgan Chase | Line of credit | ||||
Debt | ||||
Maximum borrowing capacity | $ 363,000,000 | $ 150,000,000 | ||
Line of credit | Line of credit | ||||
Debt | ||||
Maximum borrowing capacity | $ 1,823,000,000 | |||
Number of separate facilities | facility | 4 | |||
Line of credit | JPMorgan Chase | ||||
Debt | ||||
Proceeds from line of credit | $ 213,000,000 | |||
Letter of credit | ||||
Debt | ||||
Maximum borrowing capacity | $ 973,000,000 | |||
Available borrowing capacity | 721,600,000 | |||
Letter of credit | Variable Rate Demand Obligation | ||||
Debt | ||||
Available borrowing capacity | 252,000,000 | |||
Commercial paper | ||||
Debt | ||||
Line of credit, amount outstanding | $ 383,498,000 |
Debt - Pollution Control Revenu
Debt - Pollution Control Revenue Bonds (Details) | Mar. 26, 2020USD ($) |
Municipal bonds | Series 2013A Term Rate Pollution Control Revenue Bonds | |
Debt | |
Principal amount | $ 212,760,000 |
Debt - First Mortgage Bonds (De
Debt - First Mortgage Bonds (Details) | Aug. 25, 2020USD ($) |
Debt | |
Repayments of Commercial Paper | $ 439,200,000 |
Mortgage Bonds | Series 2020A First Mortgage Bonds | |
Debt | |
Principal amount | $ 450,000,000 |
Interest rate (as a percent) | 3.75% |
Electric plant, construction _3
Electric plant, construction and related agreements - Electric plant (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019 |
Public Utility Property Plant and Equipment | ||
Investment | $ 9,696,844 | $ 9,512,715 |
Accumulated Depreciation | (4,968,294) | (4,833,025) |
Total construction work in progress | 5,783,579 | 4,816,896 |
Plant acquisition adjustments | $ 197,000 | 197,000 |
Vogtle Units No. 1 & No. 2 | ||
Public Utility Property Plant and Equipment | ||
Ownership interest (as a percent) | 30.00% | |
Investment | $ 3,008,848 | 2,989,693 |
Accumulated Depreciation | $ (1,845,863) | (1,815,258) |
Vogtle Units No. 3 & No. 4 | ||
Public Utility Property Plant and Equipment | ||
Ownership interest (as a percent) | 30.00% | |
Investment | $ 57,631 | 56,991 |
Accumulated Depreciation | (5,785) | (4,956) |
Total construction work in progress | $ 5,696,342 | 4,617,654 |
Hatch Units No. 1 & No. 2 | ||
Public Utility Property Plant and Equipment | ||
Ownership interest (as a percent) | 30.00% | |
Investment | $ 952,159 | 934,567 |
Accumulated Depreciation | $ (479,628) | (462,063) |
Wansley Units No. 1 & No. 2 | ||
Public Utility Property Plant and Equipment | ||
Ownership interest (as a percent) | 30.00% | |
Investment | $ 764,315 | 749,971 |
Accumulated Depreciation | $ (370,177) | (360,014) |
Scherer Unit No. 1 | ||
Public Utility Property Plant and Equipment | ||
Ownership interest (as a percent) | 60.00% | |
Investment | $ 1,379,513 | 1,284,508 |
Accumulated Depreciation | $ (569,357) | (545,908) |
Doyle | ||
Public Utility Property Plant and Equipment | ||
Ownership interest (as a percent) | 100.00% | |
Investment | $ 139,853 | 137,513 |
Accumulated Depreciation | $ (117,005) | (113,259) |
Rocky Mountain Units No. 1, No. 2 & No. 3 | ||
Public Utility Property Plant and Equipment | ||
Ownership interest (as a percent) | 75.00% | |
Investment | $ 618,965 | 618,939 |
Accumulated Depreciation | $ (281,763) | (270,058) |
Hartwell | ||
Public Utility Property Plant and Equipment | ||
Ownership interest (as a percent) | 100.00% | |
Investment | $ 227,154 | 226,316 |
Accumulated Depreciation | $ (113,879) | (110,008) |
Hawk Road Energy Facility | ||
Public Utility Property Plant and Equipment | ||
Ownership interest (as a percent) | 100.00% | |
Investment | $ 263,673 | 260,494 |
Accumulated Depreciation | $ (63,907) | (67,065) |
Talbot | ||
Public Utility Property Plant and Equipment | ||
Ownership interest (as a percent) | 100.00% | |
Investment | $ 296,398 | 294,809 |
Accumulated Depreciation | $ (152,859) | (144,847) |
Chattahoochee | ||
Public Utility Property Plant and Equipment | ||
Ownership interest (as a percent) | 100.00% | |
Investment | $ 319,234 | 317,210 |
Accumulated Depreciation | $ (160,194) | (150,805) |
Smith Energy Facility | ||
Public Utility Property Plant and Equipment | ||
Ownership interest (as a percent) | 100.00% | |
Investment | $ 672,358 | 655,106 |
Accumulated Depreciation | $ (174,176) | (195,638) |
Wansley | ||
Public Utility Property Plant and Equipment | ||
Ownership interest (as a percent) | 30.00% | |
Investment | $ 3,942 | 3,887 |
Accumulated Depreciation | (3,847) | (3,738) |
Transmission | ||
Public Utility Property Plant and Equipment | ||
Investment | 100,344 | 96,198 |
Accumulated Depreciation | (60,688) | (59,096) |
Other production | ||
Public Utility Property Plant and Equipment | ||
Investment | 98,406 | 96,522 |
Accumulated Depreciation | $ (60,904) | (57,826) |
Scherer Unit No. 2 | ||
Public Utility Property Plant and Equipment | ||
Ownership interest (as a percent) | 60.00% | |
Investment | $ 794,051 | 789,991 |
Accumulated Depreciation | (508,262) | (472,486) |
Environmental and other generation improvements | ||
Public Utility Property Plant and Equipment | ||
Total construction work in progress | $ 87,237 | $ 199,242 |
Electric plant, construction _4
Electric plant, construction and related agreements - Narrative (Details) $ in Millions | Mar. 01, 2021MW | Apr. 30, 2020 | Aug. 31, 2018USD ($) | Dec. 31, 2020USD ($) | Jun. 30, 2020USD ($) | Dec. 31, 2020USD ($)unitMW |
Vogtle Units No. 3 & No. 4 | ||||||
Public Utility Property Plant and Equipment | ||||||
Ownership interest (as a percent) | 30.00% | 30.00% | ||||
Total investment in additional Vogtle units | $ 6,000 | $ 6,000 | ||||
Additional construction costs exceeds EAC | $ 800 | |||||
Estimated construction project-level contingency | $ 240 | |||||
Excess project contingency, total | $ 75 | |||||
Ownership amount of excess project contingency | 23 | |||||
Additional construction contingency, total | 250 | 375 | ||||
Ownership amount of additional project level contingency | $ 75 | 112.5 | ||||
Additional construction contingency, construction productivity and field support | 10 | |||||
Ownership amount of additional construction contingency, construction productivity and field support | $ 3 | |||||
Workforce reduction, percent | 20.00% | |||||
Monthly delay cost | 55 | |||||
Vogtle Units No. 3 & No. 4 | Minimum | ||||||
Public Utility Property Plant and Equipment | ||||||
COVID related costs | 325 | |||||
Ownership amount of COVID related costs | 98 | |||||
Vogtle Units No. 3 & No. 4 | Maximum | ||||||
Public Utility Property Plant and Equipment | ||||||
COVID related costs | 415 | |||||
Ownership amount of COVID related costs | $ 125 | |||||
Vogtle Units No. 3 & No. 4 | Ownership participation agreement | ||||||
Public Utility Property Plant and Equipment | ||||||
Number of additional nuclear units | unit | 2 | |||||
Ownership interest (as a percent) | 30.00% | 30.00% | ||||
Project budget | $ 7,500 | |||||
Vogtle Units No. 3 & No. 4 | EPC Agreement | Westinghouse Electric Company LLC and Stone & Webster, Inc. | ||||||
Public Utility Property Plant and Equipment | ||||||
Number of nuclear units | unit | 2 | |||||
Generating capacity of each nuclear unit (in megawatts) | MW | 1,100 | |||||
Vogtle Units No. 3 & No. 4 | Services Agreement | Westinghouse Electric Company LLC and Stone & Webster, Inc. | ||||||
Public Utility Property Plant and Equipment | ||||||
Written notice period for termination of agreement | 30 days | |||||
Vogtle Unit Number 3 | ||||||
Public Utility Property Plant and Equipment | ||||||
Delay period | 4 months | |||||
Vogtle Unit Number 4 | ||||||
Public Utility Property Plant and Equipment | ||||||
Delay period | 3 months | |||||
Monthly delay cost | $ 25 | |||||
Natural Gas Processing Plant | Subsequent Event | ||||||
Public Utility Property Plant and Equipment | ||||||
Generating capacity of each nuclear unit (in megawatts) | MW | 511 |
Electric plant, construction _5
Electric plant, construction and related agreements - Project Budget and Actual Costs (Details) - Vogtle Units No. 3 & No. 4 - USD ($) $ in Millions | 6 Months Ended | 12 Months Ended |
Jun. 30, 2020 | Dec. 31, 2020 | |
Project Budget | ||
Project-Level Contingency | $ 75 | $ 112.5 |
Remaining Project Budget | ||
Proceeds from guarantee agreement | 1,100 | |
Jointly Owned Nuclear Power Plant | ||
Project Budget | ||
Construction Costs | 5,559 | |
Financing Costs | 1,578 | |
Total Costs | 7,137 | |
Project-Level Contingency | 113 | |
Oglethorpe-Level Contingency | 250 | |
Total Contingency | 363 | |
Totals | 7,500 | |
Actual Costs | ||
Construction Costs | 4,754 | |
Financing Costs | 1,259 | |
Total Costs | 6,013 | |
Project-Level Contingency | 0 | |
Oglethorpe-Level Contingency | 0 | |
Total Contingency | 0 | |
Totals | 6,013 | |
Remaining Project Budget | ||
Construction Costs | 805 | |
Financing Costs | 319 | |
Total Costs | 1,124 | |
Project-Level Contingency | 113 | |
Oglethorpe-Level Contingency | 250 | |
Total Contingency | 363 | |
Totals | $ 1,487 |
Employee benefit plans (Details
Employee benefit plans (Details) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2020USD ($)plan | Dec. 31, 2019USD ($) | Dec. 31, 2018USD ($) | |
401(k) plan | |||
Maximum percentage of eligible annual compensation that the employee can contribute subject to IRS limitations | 60.00% | ||
Percentage of employee's contribution percent matched | 75.00% | ||
Employer matching contribution, as a percent of employee's eligible compensation | 6.00% | ||
Amount of contributions to the matching feature of the 401(k) plan | $ 1,716 | $ 1,632 | $ 1,497 |
Contribution to employer retirement contribution feature (as a percent) | 11.00% | ||
Amount of contributions to the employer retirement contribution feature of the 401(k) plan | $ 4,371 | 4,172 | $ 3,903 |
Deferred compensation plans | |||
Number of deferred compensation plans | plan | 2 | ||
Deferred compensation plan assets | $ 4,716 | 3,440 | |
Deferred compensation liability | $ 4,716 | $ 3,440 |
Nuclear insurance (Details)
Nuclear insurance (Details) $ in Millions | 12 Months Ended |
Dec. 31, 2020USD ($)reactor | |
Nuclear insurance: | |
Maximum fund for public liability claims arising from a single nuclear incident under Price-Anderson Act | $ 13,800 |
Maximum insurance coverage provided by American Nuclear Insurers to each nuclear plant | 450 |
Maximum amount that a company could be assessed per incident for each licensed reactor | 138 |
Maximum aggregate amount that a reactor can assess in a calendar period for each incident | $ 20 |
Number of nuclear reactors in which entity has ownership interest | reactor | 4 |
Maximum deferred premium amount which the entity could be assessed per incident on the basis of its joint ownership interest in four nuclear reactors | $ 165 |
Maximum deferred premium amount which the entity could be assessed per calendar year on the basis of its joint ownership interest in four nuclear reactors | $ 25 |
Period considered for inflation adjustment for maximum assessment per reactor and maximum yearly assessment | 5 years |
Maximum property damage insurance provided to nuclear generating facilities | $ 1,500 |
Additional coverage provided for losses in excess of primary coverage | 1,250 |
Sublimit for non-nuclear losses | 750 |
Maximum limits for accidental property damage occurring during construction under the policy | 2,750 |
Portion of the current maximum annual assessment for Georgia Power that would be payable by the entity based on ownership share | 42 |
Aggregate payment for claims resulting from terrorist acts in one year period | 3,200 |
Aggregate payment for claims resulting from cyber events in one year period | $ 3,200 |
Commitments (Details)
Commitments (Details) $ in Thousands | 12 Months Ended |
Dec. 31, 2020USD ($) | |
Finance and Operating Leases | |
2021 | $ 16,068 |
2022 | 15,878 |
2023 | 15,657 |
2024 | 15,183 |
2025 | 15,021 |
Thereafter | $ 41,595 |
Scherer Unit No. 2 | |
Long-term Purchase Commitment [Line Items] | |
Ownership interest (as a percent) | 60.00% |
Coal | |
Long-term Purchase Commitment [Line Items] | |
2021 | $ 5,168 |
2022 | 3,017 |
2023 | 0 |
2024 | 0 |
2025 | 0 |
Thereafter | 0 |
Nuclear Fuel | |
Long-term Purchase Commitment [Line Items] | |
2021 | 73,500 |
2022 | 33,060 |
2023 | 17,340 |
2024 | 22,650 |
2025 | 11,250 |
Thereafter | 15,930 |
Gas Transportation | |
Long-term Purchase Commitment [Line Items] | |
2021 | 63,385 |
2022 | 53,268 |
2023 | 48,707 |
2024 | 48,034 |
2025 | 46,350 |
Thereafter | 746,160 |
Maintenance Agreements | |
Long-term Purchase Commitment [Line Items] | |
Cancellation obligation | 54,007 |
2021 | 14,429 |
2022 | 14,896 |
2023 | 3,325 |
2024 | 30,316 |
2025 | 43,212 |
Thereafter | 176,751 |
Asset Retirement Obligations | |
Long-term Purchase Commitment [Line Items] | |
2021 | 17,821 |
2022 | 31,780 |
2023 | 34,372 |
2024 | 41,840 |
2025 | 74,077 |
Thereafter | $ 3,400,140 |
Quarterly financial data (una_3
Quarterly financial data (unaudited) (Details) $ in Thousands | 3 Months Ended | 12 Months Ended | |||||||||
Dec. 31, 2020USD ($) | Sep. 30, 2020USD ($) | Jun. 30, 2020USD ($) | Mar. 31, 2020USD ($) | Dec. 31, 2019USD ($) | Sep. 30, 2019USD ($) | Jun. 30, 2019USD ($) | Mar. 31, 2019USD ($) | Dec. 31, 2020USD ($) | Dec. 31, 2019USD ($) | Dec. 31, 2018USD ($) | |
Operating revenues | $ 338,761 | $ 366,239 | $ 330,944 | $ 341,674 | $ 332,209 | $ 382,623 | $ 358,860 | $ 356,600 | |||
Operating margin | 41,800 | 47,862 | 65,532 | 62,515 | 40,256 | 59,209 | 51,712 | 66,032 | $ 217,709 | $ 217,209 | $ 224,976 |
Net margin | $ (1,942) | $ 8,471 | $ 26,162 | $ 23,204 | $ 3,196 | $ 18,286 | $ 9,383 | $ 23,596 | $ 55,895 | $ 54,461 | $ 51,199 |
Targeted margins for interest ratio | 1.14 | 1.14 | 1.14 | ||||||||
Maximum | |||||||||||
Targeted margins for interest ratio | 1.14 |