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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
FORM 10-Q
☒    QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the quarterly period ended March 31, 20222023

or

☐    TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the transition period from                    to                    

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Name of Registrant, State of Incorporation, Address of Principal Executive Offices, Telephone Number, Commission File Number, IRS Employer Identification Number

ALLIANT ENERGY CORPORATION
(a Wisconsin Corporation)
4902 N. Biltmore Lane
Madison, Wisconsin 53718
Telephone (608) 458-3311
Commission File Number - 1-9894
IRS Employer Identification Number - 39-1380265

INTERSTATE POWER & LIGHT COMPANY
(an Iowa corporation)
Alliant Energy Tower
Cedar Rapids, Iowa 52401
Telephone (319) 786-4411
Commission File Number - 1-4117
IRS Employer Identification Number - 42-0331370

WISCONSIN POWER & LIGHT COMPANY
(a Wisconsin corporation)
4902 N. Biltmore Lane
Madison, Wisconsin 53718
Telephone (608) 458-3311
Commission File Number - 0-337
IRS Employer Identification Number - 39-0714890
This combined Form 10-Q is separately filed by Alliant Energy Corporation, Interstate Power and Light Company and Wisconsin Power and Light Company. Information contained in the Form 10-Q relating to Interstate Power and Light Company and Wisconsin Power and Light Company is filed by each such registrant on its own behalf. Each of Interstate Power and Light Company and Wisconsin Power and Light Company makes no representation as to information relating to registrants other than itself.

Securities registered pursuant to Section 12(b) of the Act:
Alliant Energy Corporation, Common Stock, $0.01 Par Value, Trading Symbol LNT, Nasdaq Global Select Market

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.
Alliant Energy Corporation - Yes ☒ No ☐
Interstate Power and Light Company - Yes ☒ No ☐
Wisconsin Power and Light Company - Yes ☒ No ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files).
Alliant Energy Corporation - Yes ☒ No ☐
Interstate Power and Light Company - Yes ☒ No ☐
Wisconsin Power and Light Company - Yes ☒ No ☐
Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.
Alliant Energy Corporation - Large Accelerated Filer ☒ Accelerated Filer ☐ Non-accelerated Filer ☐ Smaller Reporting Company ☐ Emerging Growth Company ☐
Interstate Power and Light Company - Large Accelerated Filer ☐ Accelerated Filer ☐ Non-accelerated Filer ☒ Smaller Reporting Company ☐ Emerging Growth Company ☐
Wisconsin Power and Light Company - Large Accelerated Filer ☐ Accelerated Filer ☐ Non-accelerated Filer ☒ Smaller Reporting Company ☐ Emerging Growth Company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.
Alliant Energy Corporation ☐
Interstate Power and Light Company ☐
Wisconsin Power and Light Company ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).
Alliant Energy Corporation - Yes ☐ No ☒
Interstate Power and Light Company - Yes ☐ No ☒
Wisconsin Power and Light Company - Yes ☐ No ☒
Number of shares outstanding of each class of common stock as of March 31, 2022:2023:
Alliant Energy Corporation, Common Stock, $0.01 par value, 250,813,728251,387,788 shares outstanding
Interstate Power and Light Company, Common Stock, $2.50 par value, 13,370,788 shares outstanding (all outstanding shares are owned beneficially and of record by Alliant Energy Corporation)
Wisconsin Power and Light Company, Common Stock, $5 par value, 13,236,601 shares outstanding (all outstanding shares are owned beneficially and of record by Alliant Energy Corporation)



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DEFINITIONS
The following abbreviations or acronyms used in this report are defined below:
Abbreviation or AcronymDefinitionAbbreviation or AcronymDefinition
20212022 Form 10-KCombined Annual Report on Form 10-K filed by Alliant Energy, IPL and WPL for the year ended Dec. 31, 2021IPLInterstate Power and Light Company
AEFAlliant Energy Finance, LLC2022IUBIowa Utilities Board
AFUDCAEFAllowance for funds used during constructionAlliant Energy Finance, LLCMDAManagement’s Discussion and Analysis of Financial Condition and Results of Operations
Alliant EnergyAFUDCAlliant Energy CorporationAllowance for funds used during constructionMISOMidcontinent Independent System Operator, Inc.
Alliant EnergyAlliant Energy CorporationMWMegawatt
ATCAmerican Transmission Company LLCMWMWhMegawattMegawatt-hour
ATC HoldingsInterest in American Transmission Company LLC and ATC Holdco LLCMWhN/AMegawatt-hourNot applicable
Corporate ServicesAlliant Energy Corporate Services, Inc.N/ANot applicable
DAECDuane Arnold Energy CenterNote(s)Combined Notes to Condensed Consolidated Financial Statements
DthDekathermOPEBOther postretirement benefits
EGUElectric generating unitPPAPurchased power agreement
EPAU.S. Environmental Protection AgencyPSCWPublic Service Commission of Wisconsin
EPSEarnings per weighted average common shareSECSecurities and Exchange Commission
FERCFinancial StatementsFederal Energy Regulatory CommissionCondensed Consolidated Financial StatementsU.S.United States of America
Financial StatementsFTRCondensed Consolidated Financial Statementstransmission rightWest RiversideWest Riverside Energy Center and Solar Facility
FTRGAAPFinancial transmission rightU.S. generally accepted accounting principlesWhiting PetroleumWhiting Petroleum Corporation
GAAPIPLU.S. generally accepted accounting principlesInterstate Power and Light CompanyWPLWisconsin Power and Light Company

FORWARD-LOOKING STATEMENTS

Statements contained in this report that are not of historical fact are forward-looking statements intended to qualify for the safe harbors from liability established by the Private Securities Litigation Reform Act of 1995. These forward-looking statements can be identified as such because the statements include words such as “may,” “believe,” “expect,” “anticipate,” “plan,” “project,” “will,” “projections,” “estimate,” or other words of similar import. Similarly, statements that describe future financial performance or plans or strategies are forward-looking statements. Such forward-looking statements are subject to certain risks and uncertainties that could cause actual results to differ materially from those expressed in, or implied by, such statements. Some, but not all, of the risks and uncertainties of Alliant Energy, IPL and WPL that could materially affect actual results include:

the impact of penalties or third-party claims related to, or in connection with, a failure to maintain the security of personally identifiable information, including associated costs to notify affected persons and to mitigate their information security concerns;
the direct or indirect effects resulting from terroristcyber security incidents includingor attacks on our physical attacks and cyber attacks,infrastructure, or responses to such incidents;
the impact of customer- and third party-owned generation, including alternative electric suppliers, in IPL’s and WPL’s service territories on system reliability, operating expenses and customers’ demand for electricity;
the impact of energy efficiency, franchise retention and customer disconnects on sales volumes and margins;
the impact that price changes may have on IPL’s and WPL’s customers’ demand for electric, gas and steam services and their ability to pay their bills;
inflation and higher interest rates;
changes in the price of delivered natural gas, transmission, purchased electricity and coal, particularly during elevated market prices, and any resulting changes to counterparty credit risk, due to shifts in supply and demand caused by market conditions, regulations and MISO’s seasonal resource adequacy process;
IPL’s and WPL’s ability to obtain adequate and timely rate relief to allow for, among other things, the recovery of and/or the return on costs, including fuel costs, operating costs, transmission costs, capacity costs, deferred expenditures, deferred tax assets, tax expense, interest expense, capital expenditures, and remaining costs related to EGUs that may be permanently closed and certain other retired assets, decreases in sales volumes, earning their authorized rates of return, and the payments to their parent of expected levels of dividends;
federal and state regulatory or governmental actions, including the impact of legislation, and regulatory agency orders;
the ability to utilize tax credits and net operating losses generated to date, and those that may be generated in the future, before they expire;
the impacts of changes in the tax code, including tax rates, minimum tax rates, and adjustments made to deferred tax assets and liabilities;obtain regulatory approval for construction projects with acceptable conditions;
the ability to complete construction of renewable generation and storage projects by planned in-service dates and within the cost targets set by regulators due to cost increases of and access to materials, equipment and commodities including due to tariffs, duties or other assessments, such as any additional tariffs resulting from U.S. Department of Commerce investigations into and any decisions made regarding the sourcing of solar project materials and equipment from certain countries, labor issues or supply shortages, the ability to successfully resolve warranty issues or contract disputes, the ability to achieve the expected level of tax benefits based on tax guidelines and project costs, and the ability to efficiently utilize the renewable generation and storage project tax benefits for the benefit of customers;
the ability to utilize tax credits generated to date, and those that may be generated in the future, before they expire, as well as the ability to transfer tax credits that may be generated in the future at adequate pricing;
disruptions to ongoing operations and the supply of materials, services, equipment and commodities needed to construct solar generation, battery storage and electric and gas distribution projects, which may result from geopolitical issues, supplier manufacturing constraints, labor issues or transportation issues, and thus affect the ability to meet capacity requirements and result in increased capacity expense;
federal and state regulatory or governmental actions, including the impact of legislation, and regulatory agency orders;
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the impacts of changes in the tax code, including tax rates, minimum tax rates, and adjustments made to deferred tax assets and liabilities;
employee workforce factors, including changes in key executives,the ability to hire and retain employees with specialized skills, impacts from employee retirements, changes in key executives, ability to create desired corporate culture, collective bargaining agreements and negotiations, work stoppages or restructurings;
disruptions in the supply and delivery of natural gas, purchased electricity and coal;
changes to the creditworthiness of, or performance of obligations by, counterparties with which Alliant Energy, IPL and WPL have contractual arrangements, including participants in the energy markets and fuel suppliers and transporters;
the impact of penalties or third-party claims related to, or in connection with, a failure to maintain the security of personally identifiable information, including associated costs to notify affected persons and to mitigate their information security concerns;
impacts that terrorist attacks may have on Alliant Energy’s, IPL’s and WPL’s operations and recovery of costs associated with restoration activities or on the operations of Alliant Energy’s investments;
any material post-closing paymentspayments related to any past asset divestitures, including the sale of Whiting Petroleum, which could result from, among other things, indemnification agreements, warranties, guarantees or litigation;
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weather effects on results of utility operations;
continued access to the capital markets on competitive terms and rates, and the actions of credit rating agencies;
changes to MISO’s resource adequacy process establishing capacity planning reserve margin and capacity accreditation requirements that may impact how and when new and existing generating facilities, including IPL’s and WPL’s additional solar generation, may be accredited with energy capacity, and may require IPL and WPL to adjust their current resource plans, to add resources to meet the requirements of MISO’s new process, or procure capacity in the market whereby such costs might not be recovered in rates;
the direct or indirect effects resulting from the ongoing novel coronavirus (COVID-19) pandemic and the spread of variant strains, including any vaccine mandates and testing requirements, on sales volumes, margins, operations, employees, labor markets, contractors, vendors, the ability to complete construction projects, supply chains, customers’ inability to pay bills, suspension of disconnects, the market value of the assets that fund pension plans and the potential for additional funding requirements, the ability of counterparties to meet their obligations, compliance with regulatory requirements, the ability to implement regulatory plans, economic conditions and access to capital markets;strains;
issues associated with environmental remediation and environmental compliance, including compliance with all environmental and emissions permits, the Coal Combustion Residuals Rule, future changes in environmental laws and regulations, including changes to Cross-State Air Pollution Rule emissions allowances and federal, state or local regulations for carbon dioxide emissions reductions from new and existing fossil-fueled EGUs, and litigation associated with environmental requirements;
increased pressure from customers, investors and other stakeholders to more rapidly reduce carbon dioxide emissions;
the ability to defend against environmental claims brought by state and federal agencies, such as the EPA, state natural resources agencies or third parties, such as the Sierra Club, and the impact on operating expenses of defending and resolving such claims;
continued access to the capital markets on competitive terms and rates, and the actions of credit rating agencies;
inflation and interest rates;
disruptions to the supply of materials, equipment and commodities needed to construct solar generation and storage projects and maintain ongoing operations, including due to geopolitical issues, shortages, labor issues or transportation issues, which may, among other potential impacts, affect the ability to meet capacity requirements and result in increased capacity expense;
possible changes to MISO’s methodology establishing capacity planning reserve margin and capacity accreditation requirements that may impact how and when new generating facilities such as IPL’s and WPL’s additional solar generation may be accredited with energy capacity and may require IPL and WPL to adjust their current resource plans, the need to add resources to comply with MISO’s proposal, or procure capacity in the market whereby such costs might not be recovered in rates;
changes in the price of delivered natural gas, transmission, purchased electricity and coal, and any resulting changes to counterparty credit risk, due to shifts in supply and demand caused by market conditions, regulations and MISO’s annual resource adequacy process;
disruptions in the supply and delivery of natural gas, purchased electricity and coal;
the direct or indirect effects resulting from breakdown or failure of equipment in the operation of electric and gas distribution systems, such as mechanical problems and explosions or fires, and compliance with electric and gas transmission and distribution safety regulations, including regulations promulgated by the Pipeline and Hazardous Materials Safety Administration;
issues related to the availability and operations of EGUs, including start-up risks, breakdown or failure of equipment, availability of warranty coverage for equipment breakdowns or failures, performance below expected or contracted levels of output or efficiency, operator error, employee safety, transmission constraints, compliance with mandatory reliability standards and risks related to recovery of resulting incremental operating, fuel-related and capital costs through rates;
impacts that excessive heat, excessive cold, storms or natural disasters may have on Alliant Energy’s, IPL’s and WPL’s operations and construction activities, and recovery of costs associated with restoration activities, or on the operations of Alliant Energy’s investments;
Alliant Energy’s ability to sustain its dividend payout ratio goal;
changes to costs of providing benefits and related funding requirements of pension and OPEB plans due to the market value of the assets that fund the plans, economic conditions, financial market performance, interest rates, timing and form of benefits payments, life expectancies and demographics;
material changes in employee-related benefit and compensation costs;costs, including settlement losses related to pension plans;
risks associated with operation and ownership of non-utility holdings;
changes in technology that alter the channels through which customers buy or utilize Alliant Energy’s, IPL’s or WPL’s products and services;
impacts on equity income from unconsolidated investments from changes in valuations andof the assets held, as well as potential changes to ATC’s authorized return on equity;
impacts of IPL’s future tax benefits from Iowa rate-making practices, including deductions for repairs expenditures, allocation of mixed service costs and state depreciation, and recoverability of the associated regulatory assets from customers, when the differences reverse in future periods;
changes to the creditworthiness of counterparties with which Alliant Energy, IPL and WPL have contractual arrangements, including participants in the energy markets and fuel suppliers and transporters;
current or future litigation, regulatory investigations, proceedings or inquiries;
reputational damage from negative publicity, protests, fines, penalties and other negative consequences resulting in regulatory and/or legal actions;
the effect of accounting standards issued periodically by standard-setting bodies;
the ability to successfully complete tax audits and changes in tax accounting methods with no material impact on earnings and cash flows; and
other factors listed in MDA and Risk Factors in Item 1A in the 20212022 Form 10-K.

Alliant Energy, IPL and WPL each assume no obligation, and disclaim any duty, to update the forward-looking statements in this report, except as required by law.
Available Information. Alliant Energy routinely posts important information on its website and considers the Investors section of its website, www.alliantenergy.com/investors, a channel of distribution for material information. Information contained on Alliant Energy’s website is not incorporated herein.
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PART I. FINANCIAL INFORMATION
ITEM 1. CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (UNAUDITED)
ALLIANT ENERGY CORPORATION
CONDENSED CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)
For the Three MonthsFor the Three Months
Ended March 31,Ended March 31,
2022202120232022
(in millions, except per share amounts)(in millions, except per share amounts)
Revenues:Revenues:Revenues:
Electric utilityElectric utility$773$701Electric utility$768$773
Gas utilityGas utility262170Gas utility276262
Other utilityOther utility1113Other utility1111
Non-utilityNon-utility2217Non-utility2222
Total revenuesTotal revenues1,068901Total revenues1,0771,068
Operating expenses:Operating expenses:Operating expenses:
Electric production fuel and purchased powerElectric production fuel and purchased power168133Electric production fuel and purchased power157168
Electric transmission serviceElectric transmission service138134Electric transmission service146138
Cost of gas soldCost of gas sold168100Cost of gas sold181168
Other operation and maintenanceOther operation and maintenance153146Other operation and maintenance174153
Depreciation and amortizationDepreciation and amortization166164Depreciation and amortization166166
Taxes other than income taxesTaxes other than income taxes2726Taxes other than income taxes3127
Total operating expensesTotal operating expenses820703Total operating expenses855820
Operating incomeOperating income248198Operating income222248
Other (income) and deductions:Other (income) and deductions:Other (income) and deductions:
Interest expenseInterest expense7469Interest expense9474
Equity income from unconsolidated investments, netEquity income from unconsolidated investments, net(15)(15)Equity income from unconsolidated investments, net(17)(15)
Allowance for funds used during constructionAllowance for funds used during construction(11)(4)Allowance for funds used during construction(19)(11)
OtherOther2Other3
Total other (income) and deductionsTotal other (income) and deductions4852Total other (income) and deductions6148
Income before income taxesIncome before income taxes200146Income before income taxes161200
Income tax expense (benefit)Income tax expense (benefit)8(28)Income tax expense (benefit)(2)8
Net income192174
Preferred dividend requirements of Interstate Power and Light Company3
Net income attributable to Alliant Energy common shareownersNet income attributable to Alliant Energy common shareowners$192$171Net income attributable to Alliant Energy common shareowners$163$192
Weighted average number of common shares outstanding:Weighted average number of common shares outstanding:Weighted average number of common shares outstanding:
BasicBasic250.6250.0Basic251.2250.6
DilutedDiluted250.9250.4Diluted251.4250.9
Earnings per weighted average common share attributable to Alliant Energy common shareowners (basic and diluted)
Earnings per weighted average common share attributable to Alliant Energy common shareowners (basic and diluted)
$0.77$0.68
Earnings per weighted average common share attributable to Alliant Energy common shareowners (basic and diluted)
$0.65$0.77

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
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ALLIANT ENERGY CORPORATION
CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)
March 31,
2022
December 31,
2021
March 31,
2023
December 31,
2022
(in millions, except per
share and share amounts)
(in millions, except per
share and share amounts)
ASSETSASSETSASSETS
Current assets:Current assets:Current assets:
Cash and cash equivalentsCash and cash equivalents$67$39Cash and cash equivalents$157$20
Accounts receivable, less allowance for expected credit lossesAccounts receivable, less allowance for expected credit losses481440Accounts receivable, less allowance for expected credit losses428516
Production fuel, at weighted average costProduction fuel, at weighted average cost3951Production fuel, at weighted average cost6053
Gas stored underground, at weighted average costGas stored underground, at weighted average cost2782Gas stored underground, at weighted average cost64132
Materials and supplies, at weighted average costMaterials and supplies, at weighted average cost119113Materials and supplies, at weighted average cost158140
Regulatory assetsRegulatory assets88104Regulatory assets193166
OtherOther271240Other132223
Total current assetsTotal current assets1,0921,069Total current assets1,1921,250
Property, plant and equipment, netProperty, plant and equipment, net15,19214,987Property, plant and equipment, net16,39616,247
Investments:Investments:Investments:
ATC HoldingsATC Holdings346338ATC Holdings363358
OtherOther187179Other206201
Total investmentsTotal investments533517Total investments569559
Other assets:Other assets:Other assets:
Regulatory assetsRegulatory assets1,8311,836Regulatory assets1,8871,880
Deferred charges and otherDeferred charges and other191144Deferred charges and other196227
Total other assetsTotal other assets2,0221,980Total other assets2,0832,107
Total assetsTotal assets$18,839$18,553Total assets$20,240$20,163
LIABILITIES AND EQUITYLIABILITIES AND EQUITYLIABILITIES AND EQUITY
Current liabilities:Current liabilities:Current liabilities:
Current maturities of long-term debtCurrent maturities of long-term debt$333$633Current maturities of long-term debt$808$408
Commercial paperCommercial paper276515Commercial paper60642
Other short-term borrowingsOther short-term borrowings50
Accounts payableAccounts payable518756
Accounts payable383436
Accrued taxes6658
Regulatory liabilitiesRegulatory liabilities251186Regulatory liabilities129206
OtherOther212226Other343351
Total current liabilitiesTotal current liabilities1,5212,054Total current liabilities1,9082,363
Long-term debt, net (excluding current portion)Long-term debt, net (excluding current portion)7,3836,735Long-term debt, net (excluding current portion)8,1327,668
Other liabilities:Other liabilities:Other liabilities:
Deferred tax liabilitiesDeferred tax liabilities1,9581,927Deferred tax liabilities1,9571,943
Regulatory liabilitiesRegulatory liabilities1,1211,085Regulatory liabilities1,1021,118
Pension and other benefit obligationsPension and other benefit obligations363374Pension and other benefit obligations273277
OtherOther416388Other540518
Total other liabilitiesTotal other liabilities3,8583,774Total other liabilities3,8723,856
Commitments and contingencies (Note 12)
00
Commitments and contingencies (Note 13)
Commitments and contingencies (Note 13)
Equity:Equity:Equity:
Alliant Energy Corporation common equity:Alliant Energy Corporation common equity:Alliant Energy Corporation common equity:
Common stock - $0.01 par value - 480,000,000 shares authorized; 250,813,728 and 250,474,529 shares outstanding33
Common stock - $0.01 par value - 480,000,000 shares authorized; 251,387,788 and 251,134,966 shares outstandingCommon stock - $0.01 par value - 480,000,000 shares authorized; 251,387,788 and 251,134,966 shares outstanding33
Additional paid-in capitalAdditional paid-in capital2,7502,749Additional paid-in capital2,7802,777
Retained earningsRetained earnings3,3363,250Retained earnings3,5593,509
Shares in deferred compensation trust - 381,397 and 383,532 shares at a weighted average cost of $31.17 and $30.59 per share(12)(12)
Accumulated other comprehensive lossAccumulated other comprehensive loss(1)
Shares in deferred compensation trust - 394,363 and 402,134 shares at a weighted average cost of $33.12 and $32.63 per shareShares in deferred compensation trust - 394,363 and 402,134 shares at a weighted average cost of $33.12 and $32.63 per share(13)(13)
Total Alliant Energy Corporation common equityTotal Alliant Energy Corporation common equity6,0775,990Total Alliant Energy Corporation common equity6,3286,276
Total liabilities and equityTotal liabilities and equity$18,839$18,553Total liabilities and equity$20,240$20,163

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
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ALLIANT ENERGY CORPORATION
CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)
For the Three MonthsFor the Three Months
Ended March 31,Ended March 31,
2022202120232022
(in millions)(in millions)
Cash flows from operating activities:Cash flows from operating activities:Cash flows from operating activities:
Net incomeNet income$192$174Net income$163$192
Adjustments to reconcile net income to net cash flows from operating activities:Adjustments to reconcile net income to net cash flows from operating activities:Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortizationDepreciation and amortization166164Depreciation and amortization166166
Deferred tax expense (benefit) and tax credits18(29)
OtherOther(6)4Other(6)12
Other changes in assets and liabilities:Other changes in assets and liabilities:Other changes in assets and liabilities:
Accounts receivableAccounts receivable(161)(126)Accounts receivable(86)(161)
Gas stored undergroundGas stored underground5520Gas stored underground6855
Derivative assetsDerivative assets(85)6Derivative assets115(85)
Regulatory assetsRegulatory assets19(4)Regulatory assets(32)19
Accounts payableAccounts payable(37)(6)Accounts payable(97)(37)
Regulatory liabilitiesRegulatory liabilities92(60)Regulatory liabilities(95)92
Deferred income taxes1558
OtherOther(17)(56)Other(8)(2)
Net cash flows from operating activitiesNet cash flows from operating activities251145Net cash flows from operating activities188251
Cash flows used for investing activities:Cash flows used for investing activities:Cash flows used for investing activities:
Construction and acquisition expenditures:Construction and acquisition expenditures:Construction and acquisition expenditures:
Utility businessUtility business(307)(214)Utility business(417)(307)
OtherOther(23)(17)Other(34)(23)
Cash receipts on sold receivablesCash receipts on sold receivables115209Cash receipts on sold receivables173115
Proceeds from sale of partial ownership interest in West RiversideProceeds from sale of partial ownership interest in West Riverside25
OtherOther(8)(16)Other(10)(8)
Net cash flows used for investing activitiesNet cash flows used for investing activities(223)(38)Net cash flows used for investing activities(263)(223)
Cash flows from (used for) financing activities:
Cash flows from financing activities:Cash flows from financing activities:
Common stock dividendsCommon stock dividends(107)(102)Common stock dividends(113)(107)
Proceeds from issuance of long-term debtProceeds from issuance of long-term debt650Proceeds from issuance of long-term debt862650
Payments to retire long-term debtPayments to retire long-term debt(300)Payments to retire long-term debt(300)
Net change in commercial paper(239)(53)
Net change in commercial paper and other short-term borrowingsNet change in commercial paper and other short-term borrowings(532)(239)
OtherOther(1)10Other(5)(1)
Net cash flows from (used for) financing activities3(145)
Net increase (decrease) in cash, cash equivalents and restricted cash31(38)
Net cash flows from financing activitiesNet cash flows from financing activities2123
Net increase in cash, cash equivalents and restricted cashNet increase in cash, cash equivalents and restricted cash13731
Cash, cash equivalents and restricted cash at beginning of periodCash, cash equivalents and restricted cash at beginning of period4056Cash, cash equivalents and restricted cash at beginning of period2440
Cash, cash equivalents and restricted cash at end of periodCash, cash equivalents and restricted cash at end of period$71$18Cash, cash equivalents and restricted cash at end of period$161$71
Supplemental cash flows information:Supplemental cash flows information:Supplemental cash flows information:
Cash paid during the period for:Cash paid during the period for:Cash paid during the period for:
InterestInterest($62)($59)Interest($93)($62)
Significant non-cash investing and financing activities:Significant non-cash investing and financing activities:Significant non-cash investing and financing activities:
Accrued capital expendituresAccrued capital expenditures$134$64Accrued capital expenditures$254$134
Beneficial interest obtained in exchange for securitized accounts receivableBeneficial interest obtained in exchange for securitized accounts receivable$227$107Beneficial interest obtained in exchange for securitized accounts receivable$153$227

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
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INTERSTATE POWER AND LIGHT COMPANY
CONDENSED CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)
For the Three MonthsFor the Three Months
Ended March 31,Ended March 31,
2022202120232022
(in millions)(in millions)
Revenues:Revenues:Revenues:
Electric utilityElectric utility$400$386Electric utility$388$400
Gas utilityGas utility13991Gas utility150139
Steam and otherSteam and other1112Steam and other1111
Total revenuesTotal revenues550489Total revenues549550
Operating expenses:Operating expenses:Operating expenses:
Electric production fuel and purchased powerElectric production fuel and purchased power6759Electric production fuel and purchased power4767
Electric transmission serviceElectric transmission service9792Electric transmission service10497
Cost of gas soldCost of gas sold8550Cost of gas sold9585
Other operation and maintenanceOther operation and maintenance8377Other operation and maintenance9583
Depreciation and amortizationDepreciation and amortization9494Depreciation and amortization9694
Taxes other than income taxesTaxes other than income taxes1414Taxes other than income taxes1614
Total operating expensesTotal operating expenses440386Total operating expenses453440
Operating incomeOperating income110103Operating income96110
Other (income) and deductions:Other (income) and deductions:Other (income) and deductions:
Interest expenseInterest expense3735Interest expense3737
Allowance for funds used during constructionAllowance for funds used during construction(3)(2)Allowance for funds used during construction(3)(3)
OtherOther1
Total other (income) and deductionsTotal other (income) and deductions3433Total other (income) and deductions3534
Income before income taxesIncome before income taxes7670Income before income taxes6176
Income tax benefitIncome tax benefit(11)(12)Income tax benefit(11)(11)
Net incomeNet income8782Net income$72$87
Preferred dividend requirements3
Net income available for common stock$87$79
Earnings per share data is not disclosed given Alliant Energy Corporation is the sole shareowner of all shares of IPL’s common stock outstanding during the periods presented.
Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
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INTERSTATE POWER AND LIGHT COMPANY
CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)
March 31,
2022
December 31,
2021
March 31,
2023
December 31,
2022
(in millions, except per
share and share amounts)
(in millions, except per
share and share amounts)
ASSETSASSETSASSETS
Current assets:Current assets:Current assets:
Cash and cash equivalentsCash and cash equivalents$62$34Cash and cash equivalents$35$15
Accounts receivable, less allowance for expected credit lossesAccounts receivable, less allowance for expected credit losses257241Accounts receivable, less allowance for expected credit losses191259
Income tax refunds receivable258
Production fuel, at weighted average costProduction fuel, at weighted average cost2829Production fuel, at weighted average cost2623
Gas stored underground, at weighted average costGas stored underground, at weighted average cost1140Gas stored underground, at weighted average cost2660
Materials and supplies, at weighted average costMaterials and supplies, at weighted average cost7170Materials and supplies, at weighted average cost9283
Regulatory assetsRegulatory assets6073Regulatory assets7585
OtherOther8569Other4993
Total current assetsTotal current assets599564Total current assets494618
Property, plant and equipment, netProperty, plant and equipment, net7,9767,983Property, plant and equipment, net8,1128,046
Other assets:Other assets:Other assets:
Regulatory assetsRegulatory assets1,3721,370Regulatory assets1,3081,301
Deferred charges and otherDeferred charges and other10379Deferred charges and other93110
Total other assetsTotal other assets1,4751,449Total other assets1,4011,411
Total assetsTotal assets$10,050$9,996Total assets$10,007$10,075
LIABILITIES AND EQUITYLIABILITIES AND EQUITYLIABILITIES AND EQUITY
Current liabilities:Current liabilities:Current liabilities:
Accounts payableAccounts payable$135$173Accounts payable$222$239
Accounts payable to associated companiesAccounts payable to associated companies4639Accounts payable to associated companies3728
Regulatory liabilities12284
Accrued taxesAccrued taxes5756Accrued taxes5952
Accrued interestAccrued interest3536Accrued interest3535
Regulatory liabilitiesRegulatory liabilities73114
OtherOther6267Other92113
Total current liabilitiesTotal current liabilities457455Total current liabilities518581
Long-term debt, netLong-term debt, net3,6443,643Long-term debt, net3,6473,646
Other liabilities:Other liabilities:Other liabilities:
Deferred tax liabilitiesDeferred tax liabilities1,1071,083Deferred tax liabilities1,0531,047
Regulatory liabilitiesRegulatory liabilities632607Regulatory liabilities624640
Pension and other benefit obligationsPension and other benefit obligations124127Pension and other benefit obligations6162
OtherOther311312Other294291
Total other liabilitiesTotal other liabilities2,1742,129Total other liabilities2,0322,040
Commitments and contingencies (Note 12)
00
Commitments and contingencies (Note 13)
Commitments and contingencies (Note 13)
Equity:Equity:Equity:
Interstate Power and Light Company common equity:Interstate Power and Light Company common equity:Interstate Power and Light Company common equity:
Common stock - $2.50 par value - 24,000,000 shares authorized; 13,370,788 shares outstandingCommon stock - $2.50 par value - 24,000,000 shares authorized; 13,370,788 shares outstanding3333Common stock - $2.50 par value - 24,000,000 shares authorized; 13,370,788 shares outstanding3333
Additional paid-in capitalAdditional paid-in capital2,8072,807Additional paid-in capital2,8072,807
Retained earningsRetained earnings935929Retained earnings970968
Total Interstate Power and Light Company common equityTotal Interstate Power and Light Company common equity3,7753,769Total Interstate Power and Light Company common equity3,8103,808
Total liabilities and equityTotal liabilities and equity$10,050$9,996Total liabilities and equity$10,007$10,075

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
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INTERSTATE POWER AND LIGHT COMPANY
CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)
For the Three MonthsFor the Three Months
Ended March 31,Ended March 31,
2022202120232022
(in millions)(in millions)
Cash flows from (used for) operating activities:
Cash flows from operating activities:Cash flows from operating activities:
Net incomeNet income$87$82Net income$72$87
Adjustments to reconcile net income to net cash flows from (used for) operating activities:
Adjustments to reconcile net income to net cash flows from operating activities:Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortizationDepreciation and amortization9494Depreciation and amortization9694
Deferred tax expense (benefit) and tax credits15(2)
Deferred tax expense and tax creditsDeferred tax expense and tax credits315
OtherOther(2)(1)Other(2)(2)
Other changes in assets and liabilities:Other changes in assets and liabilities:Other changes in assets and liabilities:
Accounts receivableAccounts receivable(128)(133)Accounts receivable(106)(128)
Income tax refunds receivableIncome tax refunds receivable(17)(3)Income tax refunds receivable(7)(17)
Gas stored undergroundGas stored underground2912Gas stored underground3429
Derivative assetsDerivative assets(43)10Derivative assets69(43)
Regulatory assets9(16)
Accounts payableAccounts payable(56)(8)
Regulatory liabilitiesRegulatory liabilities59(19)Regulatory liabilities(59)59
OtherOther(14)(69)Other(20)3
Net cash flows from (used for) operating activities89(45)
Net cash flows from operating activitiesNet cash flows from operating activities2489
Cash flows from investing activities:Cash flows from investing activities:Cash flows from investing activities:
Construction and acquisition expendituresConstruction and acquisition expenditures(96)(106)Construction and acquisition expenditures(101)(96)
Cash receipts on sold receivablesCash receipts on sold receivables115209Cash receipts on sold receivables173115
OtherOther(1)(5)Other(2)(1)
Net cash flows from investing activitiesNet cash flows from investing activities1898Net cash flows from investing activities7018
Cash flows used for financing activities:Cash flows used for financing activities:Cash flows used for financing activities:
Common stock dividendsCommon stock dividends(81)(101)Common stock dividends(70)(81)
OtherOther29Other(4)2
Net cash flows used for financing activitiesNet cash flows used for financing activities(79)(92)Net cash flows used for financing activities(74)(79)
Net increase (decrease) in cash, cash equivalents and restricted cash28(39)
Net increase in cash, cash equivalents and restricted cashNet increase in cash, cash equivalents and restricted cash2028
Cash, cash equivalents and restricted cash at beginning of periodCash, cash equivalents and restricted cash at beginning of period3450Cash, cash equivalents and restricted cash at beginning of period1534
Cash, cash equivalents and restricted cash at end of periodCash, cash equivalents and restricted cash at end of period$62$11Cash, cash equivalents and restricted cash at end of period$35$62
Supplemental cash flows information:Supplemental cash flows information:Supplemental cash flows information:
Cash (paid) refunded during the period for:
Cash paid during the period for:Cash paid during the period for:
InterestInterest($37)($37)Interest($37)($37)
Income taxes, net$—$7
Significant non-cash investing and financing activities:Significant non-cash investing and financing activities:Significant non-cash investing and financing activities:
Accrued capital expendituresAccrued capital expenditures$27$31Accrued capital expenditures$98$27
Beneficial interest obtained in exchange for securitized accounts receivableBeneficial interest obtained in exchange for securitized accounts receivable$227$107Beneficial interest obtained in exchange for securitized accounts receivable$153$227

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
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WISCONSIN POWER AND LIGHT COMPANY
CONDENSED CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)
For the Three MonthsFor the Three Months
Ended March 31,Ended March 31,
2022202120232022
(in millions)(in millions)
Revenues:Revenues:Revenues:
Electric utilityElectric utility$373$315Electric utility$380$373
Gas utilityGas utility12379Gas utility126123
Other1
Total revenuesTotal revenues496395Total revenues506496
Operating expenses:Operating expenses:Operating expenses:
Electric production fuel and purchased powerElectric production fuel and purchased power10174Electric production fuel and purchased power109101
Electric transmission serviceElectric transmission service4142Electric transmission service4241
Cost of gas soldCost of gas sold8350Cost of gas sold8683
Other operation and maintenanceOther operation and maintenance5859Other operation and maintenance6658
Depreciation and amortizationDepreciation and amortization7069Depreciation and amortization6870
Taxes other than income taxesTaxes other than income taxes1211Taxes other than income taxes1412
Total operating expensesTotal operating expenses365305Total operating expenses385365
Operating incomeOperating income13190Operating income121131
Other (income) and deductions:Other (income) and deductions:Other (income) and deductions:
Interest expenseInterest expense2726Interest expense3627
Allowance for funds used during constructionAllowance for funds used during construction(9)(2)Allowance for funds used during construction(16)(9)
OtherOther1Other1
Total other (income) and deductionsTotal other (income) and deductions1825Total other (income) and deductions2118
Income before income taxesIncome before income taxes11365Income before income taxes100113
Income tax expense (benefit)21(19)
Income tax expenseIncome tax expense1221
Net incomeNet income$92$84Net income$88$92
Earnings per share data is not disclosed given Alliant Energy Corporation is the sole shareowner of all shares of WPL’s common stock outstanding during the periods presented.
Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
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WISCONSIN POWER AND LIGHT COMPANY
CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)
March 31,
2022
December 31,
2021
(in millions, except per
share and share amounts)
ASSETS
Current assets:
Cash and cash equivalents$4$2
Accounts receivable, less allowance for expected credit losses211188
Production fuel, at weighted average cost1123
Gas stored underground, at weighted average cost1642
Materials and supplies, at weighted average cost4541
Regulatory assets2831
Prepaid gross receipts tax3040
Other10286
Total current assets447453
Property, plant and equipment, net6,7476,538
Other assets:
Regulatory assets459466
Deferred charges and other9061
Total other assets549527
Total assets$7,743$7,518
LIABILITIES AND EQUITY
Current liabilities:
Current maturities of long-term debt$250$250
Commercial paper157236
Accounts payable185190
Accounts payable to associated companies3439
Regulatory liabilities129102
Other10273
Total current liabilities857890
Long-term debt, net (excluding current portion)2,1802,179
Other liabilities:
Deferred tax liabilities759753
Regulatory liabilities489478
Pension and other benefit obligations154159
Other253236
Total other liabilities1,6551,626
Commitments and contingencies (Note 12)
00
Equity:
Wisconsin Power and Light Company common equity:
Common stock - $5 par value - 18,000,000 shares authorized; 13,236,601 shares outstanding6666
Additional paid-in capital1,8841,704
Retained earnings1,1011,053
Total Wisconsin Power and Light Company common equity3,0512,823
Total liabilities and equity$7,743$7,518
March 31,
2023
December 31,
2022
(in millions, except per
share and share amounts)
ASSETS
Current assets:
Cash and cash equivalents$86$5
Accounts receivable, less allowance for expected credit losses225244
Production fuel, at weighted average cost3429
Gas stored underground, at weighted average cost3873
Materials and supplies, at weighted average cost6354
Regulatory assets11881
Prepaid gross receipts tax3142
Other2660
Total current assets621588
Property, plant and equipment, net7,7927,722
Other assets:
Regulatory assets579579
Deferred charges and other8298
Total other assets661677
Total assets$9,074$8,987
LIABILITIES AND EQUITY
Current liabilities:
Commercial paper$60$290
Accounts payable233456
Regulatory liabilities5692
Other163111
Total current liabilities512949
Long-term debt, net3,0672,770
Other liabilities:
Deferred tax liabilities787789
Regulatory liabilities478478
Pension and other benefit obligations139140
Other378370
Total other liabilities1,7821,777
Commitments and contingencies (Note 13)
Equity:
Wisconsin Power and Light Company common equity:
Common stock - $5 par value - 18,000,000 shares authorized; 13,236,601 shares outstanding6666
Additional paid-in capital2,4132,233
Retained earnings1,2341,192
Total Wisconsin Power and Light Company common equity3,7133,491
Total liabilities and equity$9,074$8,987

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
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WISCONSIN POWER AND LIGHT COMPANY
CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)
For the Three MonthsFor the Three Months
Ended March 31,Ended March 31,
2022202120232022
(in millions)(in millions)
Cash flows from operating activities:Cash flows from operating activities:Cash flows from operating activities:
Net incomeNet income$92$84Net income$88$92
Adjustments to reconcile net income to net cash flows from operating activities:Adjustments to reconcile net income to net cash flows from operating activities:Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortizationDepreciation and amortization7069Depreciation and amortization6870
Deferred tax benefit and tax credits(2)(28)
OtherOther(3)4Other(12)(5)
Other changes in assets and liabilities:Other changes in assets and liabilities:Other changes in assets and liabilities:
Accounts receivableAccounts receivable(23)9Accounts receivable19(23)
Gas stored undergroundGas stored underground269Gas stored underground3526
Derivative assetsDerivative assets(42)(4)Derivative assets46(42)
Regulatory assetsRegulatory assets(37)10
Accounts payableAccounts payable(24)(24)Accounts payable(48)(24)
Derivative liabilitiesDerivative liabilities28(2)
Regulatory liabilitiesRegulatory liabilities32(41)Regulatory liabilities(35)32
Accrued taxesAccrued taxes218Accrued taxes1921
Deferred income taxes844
OtherOther1218Other1412
Net cash flows from operating activitiesNet cash flows from operating activities167148Net cash flows from operating activities185167
Cash flows used for investing activities:Cash flows used for investing activities:Cash flows used for investing activities:
Construction and acquisition expendituresConstruction and acquisition expenditures(212)(108)Construction and acquisition expenditures(316)(212)
Proceeds from sale of partial ownership interest in West RiversideProceeds from sale of partial ownership interest in West Riverside25
OtherOther(5)(11)Other(4)(5)
Net cash flows used for investing activitiesNet cash flows used for investing activities(217)(119)Net cash flows used for investing activities(295)(217)
Cash flows from (used for) financing activities:
Cash flows from financing activities:Cash flows from financing activities:
Common stock dividendsCommon stock dividends(44)(42)Common stock dividends(46)(44)
Capital contributions from parentCapital contributions from parent180125Capital contributions from parent180180
Proceeds from issuance of long-term debtProceeds from issuance of long-term debt297
Net change in commercial paperNet change in commercial paper(230)(79)
Net change in commercial paper(79)(109)
OtherOther(5)(4)Other(10)(5)
Net cash flows from (used for) financing activities52(30)
Net increase (decrease) in cash, cash equivalents and restricted cash2(1)
Net cash flows from financing activitiesNet cash flows from financing activities19152
Net increase in cash, cash equivalents and restricted cashNet increase in cash, cash equivalents and restricted cash812
Cash, cash equivalents and restricted cash at beginning of periodCash, cash equivalents and restricted cash at beginning of period23Cash, cash equivalents and restricted cash at beginning of period52
Cash, cash equivalents and restricted cash at end of periodCash, cash equivalents and restricted cash at end of period$4$2Cash, cash equivalents and restricted cash at end of period$86$4
Supplemental cash flows information:Supplemental cash flows information:Supplemental cash flows information:
Cash paid during the period for:Cash paid during the period for:Cash paid during the period for:
InterestInterest($23)($21)Interest($40)($23)
Significant non-cash investing and financing activities:Significant non-cash investing and financing activities:Significant non-cash investing and financing activities:
Accrued capital expendituresAccrued capital expenditures$104$32Accrued capital expenditures$152$104

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
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ALLIANT ENERGY CORPORATION
INTERSTATE POWER AND LIGHT COMPANY
WISCONSIN POWER AND LIGHT COMPANY

COMBINED NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (UNAUDITED)

NOTE 1. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
NOTE 1(a) General - The interim unaudited Financial Statements included herein have been prepared pursuant to the rules and regulations of the SEC. Accordingly, certain information and note disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted, although management believes that the disclosures are adequate to make the information presented not misleading. These Financial Statements should be read in conjunction with the financial statements and the notes thereto included in the 20212022 Form 10-K.

In the opinion of management, all adjustments, which unless otherwise noted are normal and recurring in nature, necessary for a fair presentation of the results of operations, financial position and cash flows have been made. Results for the three months ended March 31, 20222023 are not necessarily indicative of results that may be expected for the year ending December 31, 2022.2023.

A change in management’s estimates or assumptions could have a material impact on financial condition and results of operations during the period in which such change occurred. Certain prior period amounts in the Financial Statements and Notes have been reclassified to conform to the current period presentation for comparative purposes.

NOTE 1(b) Cash and Cash Equivalents and Restricted Cash - At March 31, 2022,2023, Alliant Energy’s, IPL’s and IPL’sWPL’s cash and cash equivalents included $59$148 million, $30 million and $83 million of money market fund investments, respectively, with an interest raterates of 0.3%5%.

NOTE 2. REGULATORY MATTERS
Regulatory Assets and Regulatory Liabilities -
Regulatory assets were comprised of the following items (in millions):
Alliant EnergyIPLWPLAlliant EnergyIPLWPL
March 31,
2022
December 31,
2021
March 31,
2022
December 31,
2021
March 31,
2022
December 31,
2021
March 31,
2023
December 31,
2022
March 31,
2023
December 31,
2022
March 31,
2023
December 31,
2022
Tax-relatedTax-related$949$934$896$884$53$50Tax-related$942$929$857$848$85$81
Pension and OPEB costsPension and OPEB costs453462224228229234Pension and OPEB costs385392193197192195
Asset retirement obligationsAsset retirement obligations13412894894039Asset retirement obligations1561511151104141
Commodity cost recoveryCommodity cost recovery15216041148159
DerivativesDerivatives1018437486436
Assets retired earlyAssets retired early889264662426Assets retired early677051531617
IPL’s DAEC PPA amendment84908490
IPL’s Duane Arnold Energy Center PPA amendmentIPL’s Duane Arnold Energy Center PPA amendment60666066
WPL’s Western Wisconsin gas distribution expansion investmentsWPL’s Western Wisconsin gas distribution expansion investments50525052WPL’s Western Wisconsin gas distribution expansion investments48484848
Commodity cost recovery4242224040
OtherOther11914068845156Other169146666310383
$1,919$1,940$1,432$1,443$487$497$2,080$2,046$1,383$1,386$697$660

Derivatives - Refer to Note 11 for discussion of changes in Alliant Energy’s, IPL’s and WPL’s derivative liabilities/assets during the three months ended March 31, 2023, which result in comparable changes to regulatory assets/liabilities on the balance sheets.

Regulatory liabilities were comprised of the following items (in millions):
Alliant EnergyIPLWPLAlliant EnergyIPLWPL
March 31,
2022
December 31,
2021
March 31,
2022
December 31,
2021
March 31,
2022
December 31,
2021
March 31,
2023
December 31,
2022
March 31,
2023
December 31,
2022
March 31,
2023
December 31,
2022
Tax-relatedTax-related$578$585$310$312$268$273Tax-related$575$579$302$303$273$276
Cost of removal obligationsCost of removal obligations391384256252135132Cost of removal obligations403398261259142139
DerivativesDerivatives2581661257713389Derivatives117210641155395
Electric transmission cost recoveryElectric transmission cost recovery505129272124Electric transmission cost recovery26201910710
WPL’s West Riverside liquidated damagesWPL’s West Riverside liquidated damages35363536WPL’s West Riverside liquidated damages24322432
Commodity cost recoveryCommodity cost recovery2240838142
OtherOther604934232626Other644543292116
$1,372$1,271$754$691$618$580$1,231$1,324$697$754$534$570

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NOTE 3. PROPERTY, PLANT AND EQUIPMENT
In March 2023, Madison Gas and Electric Company acquired a partial ownership interest in West Riverside, and the related proceeds are included in “Proceeds from sale of partial ownership interest in West Riverside” in investing activities in Alliant Energy’s and WPL’s cash flow statements for the three months ended March 31, 2023. As a result of this transaction, WPL’s undivided current ownership interest in West Riverside is 87.6%.

NOTE 4. RECEIVABLES
NOTE 4(a) - Accounts Receivable - For the three months ended March 31, 2023, Alliant Energy’s, IPL’s and WPL’s gross write-offs for accounts receivable, which originated in 2022, were $5 million, $3 million and $2 million, respectively.

NOTE 4(b) - Sales of Accounts Receivable - IPL maintains a Receivables Purchase and Sale Agreement (Receivables Agreement) whereby it may sell its customer accounts receivables, unbilled revenues and certain other accounts receivables to a third party through wholly-owned and consolidated special purpose entities. In March 2023, IPL amended and extended through March 2024 the purchase commitment from the third party to which it sells its receivables. The transfers of receivables meet the criteria for sale accounting established by the transfer of financial assets accounting rules. As of March 31, 2022,2023, IPL had $109$21 million of available capacity under its sales of accounts receivable program. IPL’s maximum and average outstanding cash proceeds (based on daily outstanding balances) related to the sales of accounts receivable program for the three months ended March 31 were as follows (in millions):
2022202120232022
Maximum outstanding aggregate cash proceedsMaximum outstanding aggregate cash proceeds$36$100Maximum outstanding aggregate cash proceeds$89$36
Average outstanding aggregate cash proceedsAverage outstanding aggregate cash proceeds430Average outstanding aggregate cash proceeds584

The attributes of IPL’s receivables sold under the Receivables Agreement were as follows (in millions):
March 31, 2022December 31, 2021March 31, 2023December 31, 2022
Customer accounts receivableCustomer accounts receivable$142$125Customer accounts receivable$161$145
Unbilled utility revenuesUnbilled utility revenues96104Unbilled utility revenues94132
Receivables sold to third partyReceivables sold to third party238229Receivables sold to third party255277
Less: cash proceedsLess: cash proceeds11Less: cash proceeds8980
Deferred proceedsDeferred proceeds237228Deferred proceeds166197
Less: allowance for expected credit lossesLess: allowance for expected credit losses1014Less: allowance for expected credit losses1312
Fair value of deferred proceedsFair value of deferred proceeds$227$214Fair value of deferred proceeds$153$185

As of March 31, 2022,2023, outstanding receivables past due under the Receivables Agreement were $24$26 million. Additional attributes of IPL’s receivables sold under the Receivables Agreement for the three months ended March 31 were as follows (in millions):
2022202120232022
CollectionsCollections$561$529Collections$591$561
Write-offs, net of recoveriesWrite-offs, net of recoveries22Write-offs, net of recoveries22

NOTE 4.5. INVESTMENTS
Unconsolidated Equity Investments - Alliant Energy’s equity (income) loss from unconsolidated investments accounted for under the equity method of accounting for the three months ended March 31 was as follows (in millions):
2022202120232022
ATC HoldingsATC Holdings($11)($11)ATC Holdings($13)($11)
OtherOther(4)(4)Other(4)(4)
($15)($15)($17)($15)

NOTE 5.6. COMMON EQUITY
Common Share Activity - A summary of Alliant Energy’s common stock activity was as follows:
Shares outstanding, January 1, 20222023250,474,529251,134,966 
Shareowner Direct Plan116,431118,488 
Equity-based compensation plans222,768134,334 
Shares outstanding, March 31, 20222023250,813,728251,387,788 

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Changes in Shareowners’ Equity - A summary of changes in shareowners’ equity was as follows (in millions):
Alliant EnergyTotal Alliant Energy Common Equity
AccumulatedShares inCumulative
AdditionalOtherDeferredPreferred
CommonPaid-InRetainedComprehensiveCompensationStockTotal
StockCapitalEarningsLossTrustof IPLEquity
Three Months Ended March 31, 2022
Beginning balance, December 31, 2021$3$2,749$3,250$—($12)$—$5,990
Net income attributable to Alliant Energy common shareowners192192
Common stock dividends ($0.4275 per share)(107)(107)
Shareowner Direct Plan issuances77
Equity-based compensation plans and other(6)1(5)
Ending balance, March 31, 2022$3$2,750$3,336$—($12)$—$6,077
Three Months Ended March 31, 2021
Beginning balance, December 31, 2020$2$2,704$2,994($1)($11)$200$5,888
Net income attributable to Alliant Energy common shareowners171171
Common stock dividends ($0.4025 per share)(102)(102)
Shareowner Direct Plan issuances178
Equity-based compensation plans and other11
Ending balance, March 31, 2021$3$2,712$3,063($1)($11)$200$5,966
Alliant EnergyAccumulatedShares in
AdditionalOtherDeferredTotal
CommonPaid-InRetainedComprehensiveCompensationCommon
StockCapitalEarningsLossTrustEquity
Three Months Ended March 31, 2023
Beginning balance, December 31, 2022$3$2,777$3,509$—($13)$6,276
Net income attributable to Alliant Energy common shareowners163163
Common stock dividends ($0.4525 per share)(113)(113)
Shareowner Direct Plan issuances66
Equity-based compensation plans and other(3)(3)
Other comprehensive loss, net of tax(1)(1)
Ending balance, March 31, 2023$3$2,780$3,559($1)($13)$6,328
Three Months Ended March 31, 2022
Beginning balance, December 31, 2021$3$2,749$3,250$—($12)$5,990
Net income attributable to Alliant Energy common shareowners192192
Common stock dividends ($0.4275 per share)(107)(107)
Shareowner Direct Plan issuances77
Equity-based compensation plans and other(6)1(5)
Ending balance, March 31, 2022$3$2,750$3,336$—($12)$6,077
IPLIPLTotal IPL Common EquityIPLAdditionalTotal
AdditionalCumulativeCommonPaid-InRetainedCommon
CommonPaid-InRetainedPreferredTotalStockCapitalEarningsEquity
Three Months Ended March 31, 2023Three Months Ended March 31, 2023
Beginning balance, December 31, 2022Beginning balance, December 31, 2022$33$2,807$968$3,808
Net incomeNet income7272
Common stock dividendsCommon stock dividends(70)(70)
StockCapitalEarningsStockEquity
Ending balance, March 31, 2023Ending balance, March 31, 2023$33$2,807$970$3,810
Three Months Ended March 31, 2022Three Months Ended March 31, 2022Three Months Ended March 31, 2022
Beginning balance, December 31, 2021Beginning balance, December 31, 2021$33$2,807$929$—$3,769Beginning balance, December 31, 2021$33$2,807$929$3,769
Net income available for common stock8787
Net incomeNet income8787
Common stock dividendsCommon stock dividends(81)(81)Common stock dividends(81)(81)
Ending balance, March 31, 2022Ending balance, March 31, 2022$33$2,807$935$—$3,775Ending balance, March 31, 2022$33$2,807$935$3,775
Three Months Ended March 31, 2021
Beginning balance, December 31, 2020$33$2,752$979$200$3,964
Net income available for common stock7979
Common stock dividends(101)(101)
Ending balance, March 31, 2021$33$2,752$957$200$3,942
WPLWPLAdditionalTotalWPLAdditionalTotal
CommonPaid-InRetainedCommonCommonPaid-InRetainedCommon
StockCapitalEarningsEquityStockCapitalEarningsEquity
Three Months Ended March 31, 2023Three Months Ended March 31, 2023
Beginning balance, December 31, 2022Beginning balance, December 31, 2022$66$2,233$1,192$3,491
Net incomeNet income8888
Common stock dividendsCommon stock dividends(46)(46)
Capital contributions from parentCapital contributions from parent180180
Ending balance, March 31, 2023Ending balance, March 31, 2023$66$2,413$1,234$3,713
Three Months Ended March 31, 2022Three Months Ended March 31, 2022Three Months Ended March 31, 2022
Beginning balance, December 31, 2021Beginning balance, December 31, 2021$66$1,704$1,053$2,823Beginning balance, December 31, 2021$66$1,704$1,053$2,823
Net incomeNet income9292Net income9292
Common stock dividendsCommon stock dividends(44)(44)Common stock dividends(44)(44)
Capital contributions from parentCapital contributions from parent180180Capital contributions from parent180180
Ending balance, March 31, 2022Ending balance, March 31, 2022$66$1,884$1,101$3,051Ending balance, March 31, 2022$66$1,884$1,101$3,051
Three Months Ended March 31, 2021
Beginning balance, December 31, 2020$66$1,459$953$2,478
Net income8484
Common stock dividends(42)(42)
Capital contributions from parent125125
Ending balance, March 31, 2021$66$1,584$995$2,645
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NOTE 6.7. DEBT
NOTE 6(a)7(a) Short-term Debt - In March 2023, Alliant Energy, IPL and WPL extended their single credit facility agreement, which currently expires in December 2027, and reallocated credit facility capacity amounts to $450 million for Alliant Energy at the parent company level, $250 million for IPL and $300 million for WPL, within the $1 billion total commitment. Information regarding Alliant Energy’s, IPL’s and WPL’s commercial paper classified as short-term debt was as follows (dollars in millions):
March 31, 2022Alliant EnergyIPLWPL
March 31, 2023March 31, 2023Alliant EnergyIPLWPL
Amount outstandingAmount outstanding$276$—$157Amount outstanding$60$—$60
Weighted average interest ratesWeighted average interest rates0.6%N/A0.5%Weighted average interest rates5.1%N/A5.1%
Available credit facility capacityAvailable credit facility capacity$724$250$143Available credit facility capacity$940$250$240
Alliant EnergyIPLWPLAlliant EnergyWPL
Three Months Ended March 31Three Months Ended March 31202220212022202120222021Three Months Ended March 312023202220232022
Maximum amount outstanding (based on daily outstanding balances)Maximum amount outstanding (based on daily outstanding balances)$577$578$—$—$252$275Maximum amount outstanding (based on daily outstanding balances)$793$577$349$252
Average amount outstanding (based on daily outstanding balances)Average amount outstanding (based on daily outstanding balances)$443$424$—$—$205$189Average amount outstanding (based on daily outstanding balances)$574$443$304$205
Weighted average interest ratesWeighted average interest rates0.3%0.2%—%—%0.3%0.2%Weighted average interest rates4.8%0.3%4.8%0.3%

In January 2023, AEF received $50 million of proceeds from its December 2022 term loan credit agreement, which was classified as “Other short-term borrowings” on Alliant Energy’s balance sheet as of March 31, 2023.

NOTE 6(b)7(b) Long-term Debt - In February 2022, AEFMarch 2023, WPL issued $350$300 million of 3.6%4.95% debentures due 2033. The debentures were issued as green bonds, and an amount equal to or in excess of the net proceeds will be allocated or disbursed for the development and acquisition of WPL’s solar EGUs.

Convertible Senior Notes - In March 2023, Alliant Energy issued $575 million of 3.875% convertible senior notes due 2032. The(the Notes), which are senior unsecured obligations, and used the net proceeds from the issuance were used to reduce Alliant Energy’s outstanding commercial paper and for general corporate purposes. The Notes will mature on March 15, 2026 unless earlier converted or repurchased, and no sinking fund is provided for the Notes. Alliant Energy may not redeem the Notes prior to the maturity date. Holders may convert their Notes at their option at any time prior to the close of business on the business day immediately preceding December 15, 2025 only under the following circumstances:

during any calendar quarter commencing after the calendar quarter ending on June 30, 2023 (and only during such calendar quarter), if the last reported sale price of Alliant Energy’s common stock for at least 20 trading days (whether or not consecutive) during a period of 30 consecutive trading days ending on, and including, the last trading day of the immediately preceding calendar quarter is greater than or equal to 130% of the conversion price on each applicable trading day during such period;
during the 5 business day period after any 10 consecutive trading day period (the “measurement period”) in which the trading price (as defined in the related Indenture) per $1,000 principal amount of Notes for each trading day of the measurement period was less than 98% of the product of the last reported sale price of Alliant Energy’s common stock and the conversion rate on each such trading day; or
upon the occurrence of specified corporate events.

On or after December 15, 2025 until the close of business on the business day immediately preceding the maturity date, holders may convert all or any portion of their Notes at any time, regardless of the foregoing circumstances. Upon conversion of the Notes, Alliant Energy will pay cash up to the aggregate principal amount of the Notes to be converted and pay or deliver, as the case may be, cash, shares of its common stock or a combination of cash and shares of its common stock, at its election, in respect of the remainder, if any, of its conversion obligation in excess of the aggregate principal amount of the Notes being converted.

The conversion rate will initially be 15.5461 shares of common stock per $1,000 principal amount of Notes (equivalent to an initial conversion price of approximately $64.32 per share of Alliant Energy’s common stock). The conversion rate will be subject to adjustment in some events but will not be adjusted for any accrued and unpaid interest. In addition, following certain corporate events that occur prior to the maturity date, Alliant Energy will, in certain circumstances, increase the conversion rate for a holder who elects to convert its Notes in connection with such a corporate event.

If Alliant Energy undergoes a fundamental change (as defined in the related Indenture), then, subject to certain conditions, holders of the Notes may require Alliant Energy to repurchase for cash all or any portion of its Notes at a repurchase price equal to 100% of the principal amount of the Notes to be repurchased, plus accrued and unpaid interest to, but excluding, the fundamental change repurchase date.

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In March 2022, AEF entered into2023, the conditions allowing holders of the Notes to convert during March 2023 were not met, and as a $300 million variable rate (1%result, the Notes were classified as “Long-term debt, net” on Alliant Energy’s balance sheet as of March 31, 2022) term loan credit agreement (with2023. As of March 31, 2023, the net carrying amount of the Notes was $565 million, with unamortized debt issuance costs of $10 million, and the estimated fair value (Level 2) of the Notes was $595 million. As of March 31, 2023, there were no shares of Alliant Energy as guarantor), which expiresEnergy’s common stock related to the potential conversion of the Notes included in March 2024,diluted EPS based on Alliant Energy’s average stock prices and used the borrowings under this agreement to retire its $300 million variable rate term loan credit agreement that expired in March 2022.relevant terms of the Notes.

NOTE 7.8. REVENUES
Disaggregation of revenues from contracts with customers, which correlates to revenues for each reportable segment, was as follows (in millions):
Alliant EnergyIPLWPLAlliant EnergyIPLWPL
Three Months Ended March 31Three Months Ended March 31202220212022202120222021Three Months Ended March 31202320222023202220232022
Electric Utility:Electric Utility:Electric Utility:
Retail - residentialRetail - residential$293$262$150$139$143$123Retail - residential$285$293$143$150$142$143
Retail - commercialRetail - commercial1881721181107062Retail - commercial1851881121187370
Retail - industrialRetail - industrial21120211111210090Retail - industrial216211107111109100
WholesaleWholesale474015113229Wholesale464712153432
Bulk power and otherBulk power and other34256142811Bulk power and other36341462228
Total Electric UtilityTotal Electric Utility773701400386373315Total Electric Utility768773388400380373
Gas Utility:Gas Utility:Gas Utility:
Retail - residentialRetail - residential1589985527347Retail - residential16715893857473
Retail - commercialRetail - commercial825340274226Retail - commercial888244404442
Retail - industrialRetail - industrial855332Retail - industrial784533
Transportation/otherTransportation/other14139954Transportation/other14149955
Total Gas UtilityTotal Gas Utility2621701399112379Total Gas Utility276262150139126123
Other Utility:Other Utility:Other Utility:
SteamSteam9999Steam109109
Other utilityOther utility24231Other utility1212
Total Other UtilityTotal Other Utility111311121Total Other Utility11111111
Non-Utility and Other:Non-Utility and Other:Non-Utility and Other:
Travero and otherTravero and other2217Travero and other2222
Total Non-Utility and OtherTotal Non-Utility and Other2217Total Non-Utility and Other2222
Total revenuesTotal revenues$1,068$901$550$489$496$395Total revenues$1,077$1,068$549$550$506$496
NOTE 8.9. INCOME TAXES
Income Tax Rates - Overall effective income tax rates, which were computed by dividing income tax expense (benefit) by income before income taxes, were as follows. The effective income tax rates were different than the federal statutory rate primarily due to state income taxes, production tax credits, amortization of excess deferred taxes and the effect of rate-making on property-related differences. The increases in Alliant Energy’s and WPL’s overall effective income tax rates for the three months ended March 31, 2022 compared to the same period in 2021 were primarily due to decreased amortization of excess deferred taxes primarily at WPL.
Alliant EnergyIPLWPL
202220212022202120222021
Overall income tax rate4%(19%)(14%)(17%)19%(29%)
Alliant EnergyIPLWPL
202320222023202220232022
Overall income tax rate(1%)4%(18%)(14%)12%19%

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Deferred Tax Assets and Liabilities -
Carryforwards - At March 31, 2022,2023, the carryforwards and expiration dates were estimated as follows (in millions):
Range of Expiration DatesAlliant EnergyIPLWPL
Federal net operating losses2037$94$87$1
State net operating losses2022-2042578132
Federal tax credits2022-2042589369197

Iowa Tax Reform - In March 2022, Iowa tax reform was enacted, which would reduce the current 9.8% Iowa corporate income tax rate beginning in 2023 if certain state income tax revenue triggers are satisfied. Annually, and by each November 1, the Iowa Department of Revenue will establish corporate income tax rates for the next tax year based on net corporate income tax receipts for the prior tax year. Rate reductions are currently expected to occur over a period of several years, with a target corporate income tax rate of 5.5%. Alliant Energy is currently unable to predict with certainty the timing or amount of any rate reductions. The majority of any reduction in income tax expense as a result of the lower Iowa corporate income tax rate is currently expected to reduce rates for IPL’s customers. In addition, after the 2023 corporate income tax rate is known in the fourth quarter of 2022, Alliant Energy currently expects to record a charge related to the remeasurement of accumulated deferred income tax assets at its non-utility businesses.
Range of Expiration DatesAlliant EnergyIPLWPL
State net operating losses2025-2043$535$12$1
Federal tax credits2027-2043698468218

NOTE 9.10. BENEFIT PLANS
NOTE 9(a)10(a) Pension and OPEB Plans -
Net Periodic Benefit Costs - The components of net periodic benefit costs for sponsored defined benefit pension and OPEB plans for the three months ended March 31 are included below (in millions). For IPL and WPL, amounts are for their plan participants covered under plans they sponsor, as well as amounts directly assigned to them related to certain participants in the Alliant Energy and Corporate Services sponsored plans.
Defined Benefit Pension PlansOPEB Plans
Alliant Energy2022202120222021
Service cost$2$3$1$1
Interest cost9811
Expected return on plan assets(17)(17)(1)(1)
Amortization of actuarial loss81011
$2$4$2$2
Defined Benefit Pension PlansOPEB Plans
IPL2022202120222021
Service cost$2$2$—$—
Interest cost4411
Expected return on plan assets(8)(8)(1)(1)
Amortization of actuarial loss34
$1$2$—$—
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Defined Benefit Pension PlansOPEB PlansDefined Benefit Pension PlansOPEB Plans
WPL2022202120222021
Alliant EnergyAlliant Energy2023202220232022
Service costService cost$1$1$—$—Service cost$1$2$1$1
Interest costInterest cost441Interest cost11921
Expected return on plan assetsExpected return on plan assets(8)(8)Expected return on plan assets(13)(17)(1)(1)
Amortization of actuarial lossAmortization of actuarial loss451Amortization of actuarial loss781
$1$2$1$1
$6$2$2$2
Defined Benefit Pension PlansOPEB Plans
IPL2023202220232022
Service cost$1$2$—$—
Interest cost5411
Expected return on plan assets(7)(8)(1)(1)
Amortization of actuarial loss33
$2$1$—$—
Defined Benefit Pension PlansOPEB Plans
WPL2023202220232022
Service cost$—$1$—$—
Interest cost5411
Expected return on plan assets(5)(8)
Amortization of actuarial loss34
$3$1$1$1

NOTE 9(b)10(b) Equity-based Compensation Plans - A summary of compensation expense, including amounts allocated to IPL and WPL, and the related income tax benefits recognized for share-based compensation awards for the three months ended March 31 was as follows (in millions):
Alliant EnergyIPLWPLAlliant EnergyIPLWPL
202220212022202120222021202320222023202220232022
Compensation expenseCompensation expense$4$3$2$1$2$1Compensation expense$3$4$2$2$1$2
Income tax benefitsIncome tax benefits111Income tax benefits111

As of March 31, 2022,2023, Alliant Energy’s, IPL’s and WPL’s total unrecognized compensation cost related to share-based compensation awards was $15$18 million, $8$9 million and $6$8 million, respectively, which is expected to be recognized over a weighted average period of between 1 year and 2 years.
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For the three months ended March 31, 2022,2023, performance shares, performance restricted stock units and restricted stock units were granted to key employees under existing plans as follows. These shares and units will be paid out in shares of common stock, and are therefore accounted for as equity awards.
Weighted AverageWeighted Average
GrantsGrant Date Fair ValueGrantsGrant Date Fair Value
Performance sharesPerformance shares70,240$54.45Performance shares100,055$55.68
Performance restricted stock unitsPerformance restricted stock units80,25256.62Performance restricted stock units114,32552.73
Restricted stock unitsRestricted stock units74,36056.62Restricted stock units99,94152.78

As of March 31, 2022, 322,2882023, 170,209 shares were included in the calculation of diluted EPS related to the nonvested equity awards.

NOTE 10.11. DERIVATIVE INSTRUMENTS
Commodity Derivatives -
Notional Amounts - As of March 31, 2022,2023, gross notional amounts and settlement/delivery years related to outstanding swap contracts, option contracts, physical forward contracts and FTRs that were accounted for as commodity derivative instruments were as follows (units in thousands):
FTRsNatural GasCoalDiesel FuelElectricityFTRsNatural GasCoal
MWhsYearsDthsYearsTonsYearsGallonsYearsMWhsYearsMWhsYearsDthsYearsTonsYears
Alliant EnergyAlliant Energy3,304 2022175,658 2022-20302,653 2022-20232,268 2022Alliant Energy9222023-20253,276 2023209,102 2023-2032662 2023
IPLIPL784 202294,175 2022-20301,053 2022-2023— IPL3912023-20251,338 2023101,863 2023-2030325 2023
WPLWPL2,520 202281,483 2022-20301,600 2022-20232,268 2022WPL53120231,938 2023107,239 2023-2032337 2023
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Financial Statement Presentation - Derivative instruments are recorded at fair value each reporting date on the balance sheets as assets or liabilities as follows (in millions):
Alliant EnergyIPLWPLAlliant EnergyIPLWPL
March 31,
2022
December 31,
2021
March 31,
2022
December 31,
2021
March 31,
2022
December 31,
2021
March 31,
2023
December 31,
2022
March 31,
2023
December 31,
2022
March 31,
2023
December 31,
2022
Current derivative assetsCurrent derivative assets$151$113$68$48$83$65Current derivative assets$28$111$17$69$11$42
Non-current derivative assetsNon-current derivative assets1106359365127Non-current derivative assets9412652694257
Current derivative liabilitiesCurrent derivative liabilities683434Current derivative liabilities655926403919
Non-current derivative liabilitiesNon-current derivative liabilities1111Non-current derivative liabilities3020862214

During the three months ended March 31, 2022,2023, Alliant Energy’s, IPL’s and WPL’s current derivative assets decreased primarily due to settlements of natural gas, FTR and electricity contracts. Alliant Energy’s and WPL’s derivative liabilities increased primarily as a result of higherdue to lower natural gas prices. IPL’s current derivative liabilities decreased primarily due to settlements of natural gas contracts. Based on IPL’s and WPL’s natural gas cost recovery mechanisms, thisthe changes in the fair value of derivative liabilities/assets resulted in corresponding increases in derivativecomparable changes to regulatory assets/liabilities on the balance sheets.

Credit Risk-related Contingent Features - Various agreements contain credit risk-related contingent features, including requirements to maintain certain credit ratings and/or limitations on liability positions under the agreements based on credit ratings. Certain of these agreements with credit risk-related contingency features are accounted for as derivative instruments. In the event of a material change in creditworthiness or if liability positions exceed certain contractual limits, credit support may need to be provided in the form of letters of credit or cash collateral up to the amount of exposure under the contracts, or the contracts may need to be unwound and underlying liability positions paid. At March 31, 20222023 and December 31, 2021,2022, the aggregate fair value of all derivative instruments with credit risk-related contingent features in a net liability position was not materially different than amounts that would be required to be posted as credit support to counterparties by Alliant Energy, IPL or WPL if the most restrictive credit risk-related contingent features for derivative agreements in a net liability position were triggered.

Balance Sheet Offsetting - The fair value amounts of derivative instruments subject to a master netting arrangement are not netted by counterparty on the balance sheets. However, if the fair value amounts of derivative instruments by counterparty were netted, amounts would not be materially different from gross amounts of derivative assets and derivative liabilities at March 31, 2022 and December 31, 2021. related to commodity contracts would have been presented on the balance sheets as follows (in millions):
Alliant EnergyIPLWPL
GrossGrossGross
(as reported)Net(as reported)Net(as reported)Net
March 31, 2023
Derivative assets$122$89$69$51$53$38
Derivative liabilities956234166146
December 31, 2022
Derivative assets2371931381089985
Derivative liabilities793546163319

Fair value amounts recognized for the right to reclaim cash collateral (receivable) or the obligation to return cash collateral (payable) are not offset against fair value amounts recognized for derivative instruments executed with the same counterparty under the same master netting arrangement.

Interest Rate Derivative - In January 2023, AEF entered into a $300 million interest rate swap maturing in January 2026 to mitigate interest rate risk. Under the terms of the swap, AEF exchanged a variable interest rate for a fixed interest rate of 3.93% on a portion of its variable-rate term loan borrowings. The related interest rate derivative was valued based on quoted prices that utilize current market interest rate forecasts. As of March 31, 2023, $1 million of non-current interest rate derivative liabilities were recorded in “Other liabilities” on Alliant Energy’s balance sheet. This interest rate derivative was designated as a cash flow hedge, with changes in fair value recorded as other comprehensive income/loss. As of March 31, 2023, accumulated other comprehensive loss included $1 million of losses related to the interest rate swap. For the three months ended March 31, 2023, a $1 million reduction to interest expense was recorded in Alliant Energy’s income statement related to the interest rate swap.

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NOTE 11.12. FAIR VALUE MEASUREMENTS
Fair Value of Financial Instruments - The carrying amounts of current assets and current liabilities approximate fair value because of the short maturity of such financial instruments. Carrying amounts and related estimated fair values of other financial instruments were as follows (in millions):
Alliant EnergyAlliant EnergyMarch 31, 2022December 31, 2021Alliant EnergyMarch 31, 2023December 31, 2022
Fair ValueFair ValueFair ValueFair Value
CarryingLevelLevelLevelCarryingLevelLevelLevelCarryingLevelLevelLevelCarryingLevelLevelLevel
Amount123TotalAmount123TotalAmount123TotalAmount123Total
Assets:Assets:Assets:
Money market fund investmentsMoney market fund investments$59 $59 $— $— $59 $32 $32 $— $— $32 Money market fund investments$148 $148 $— $— $148 $10 $10 $— $— $10 
Derivatives261  251 10 261 176 — 146 30 176 
Commodity derivativesCommodity derivatives122  116 6 122 237 — 206 31 237 
Deferred proceedsDeferred proceeds227   227 227 214 — — 214 214 Deferred proceeds153   153 153 185 — — 185 185 
Liabilities:Liabilities:Liabilities:
Derivatives7  7  7 — 
Commodity derivativesCommodity derivatives95  84 11 95 79 — 67 12 79 
Interest rate derivativesInterest rate derivatives1  1  1 — — — — — 
Long-term debt (incl. current maturities)Long-term debt (incl. current maturities)7,716  7,971 1 7,972 7,368 — 8,329 8,330 Long-term debt (incl. current maturities)8,940  8,461 1 8,462 8,076 — 7,338 7,339 
IPLIPLMarch 31, 2022December 31, 2021IPLMarch 31, 2023December 31, 2022
Fair ValueFair ValueFair ValueFair Value
CarryingLevelLevelLevelCarryingLevelLevelLevelCarryingLevelLevelLevelCarryingLevelLevelLevel
Amount123TotalAmount123TotalAmount123TotalAmount123Total
Assets:Assets:Assets:
Money market fund investmentsMoney market fund investments$59 $59 $— $— $59 $32 $32 $— $— $32 Money market fund investments$30 $30 $— $— $30 $10 $10 $— $— $10 
Derivatives127  120 7 127 84 — 65 19 84 
Commodity derivativesCommodity derivatives69  63 6 69 138 — 111 27 138 
Deferred proceedsDeferred proceeds227   227 227 214 — — 214 214 Deferred proceeds153   153 153 185 — — 185 185 
Liabilities:Liabilities:Liabilities:
Derivatives4  4  4 — 
Commodity derivativesCommodity derivatives34  28 6 34 46 — 35 11 46 
Long-term debtLong-term debt3,644  3,738  3,738 3,643 — 4,124 — 4,124 Long-term debt3,647  3,335  3,335 3,646 — 3,228 — 3,228 
WPLWPLMarch 31, 2022December 31, 2021WPLMarch 31, 2023December 31, 2022
Fair ValueFair ValueFair ValueFair Value
CarryingLevelLevelLevelCarryingLevelLevelLevelCarryingLevelLevelLevelCarryingLevelLevelLevel
Amount123TotalAmount123TotalAmount123TotalAmount123Total
Assets:Assets:Assets:
Derivatives$134 $— $131 $3 $134 $92 $— $81 $11 $92 
Money market fund investmentsMoney market fund investments$83 $83 $— $— $83 $— $— $— $— $— 
Commodity derivativesCommodity derivatives53  53  53 99 — 95 99 
Liabilities:Liabilities:Liabilities:
Derivatives3  3  3 — — 
Long-term debt (incl. current maturities)2,430  2,592  2,592 2,429 — 2,862 — 2,862 
Commodity derivativesCommodity derivatives61  56 5 61 33 — 32 33 
Long-term debtLong-term debt3,067  2,939  2,939 2,770 — 2,542 — 2,542 

Information for fair value measurements using significant unobservable inputs (Level 3 inputs) was as follows (in millions):
Alliant EnergyAlliant EnergyCommodity Contract DerivativeAlliant EnergyCommodity Contract Derivative
Assets and (Liabilities), netDeferred ProceedsAssets and (Liabilities), netDeferred Proceeds
Three Months Ended March 31Three Months Ended March 312022202120222021Three Months Ended March 312023202220232022
Beginning balance, January 1Beginning balance, January 1$29$29$214$188Beginning balance, January 1$19$29$185$214
Total net losses included in changes in net assets (realized/unrealized)Total net losses included in changes in net assets (realized/unrealized)(6)(6)Total net losses included in changes in net assets (realized/unrealized)(4)(6)
Settlements (a)Settlements (a)(13)(7)13(81)Settlements (a)(20)(13)(32)13
Ending balance, March 31Ending balance, March 31$10$16$227$107Ending balance, March 31($5)$10$153$227
The amount of total net losses for the period included in changes in net liabilities attributable to the change in unrealized losses relating to liabilities held at March 31($5)($6)$—$—
The amount of total net losses for the period included in changes in net assets attributable to the change in unrealized losses relating to assets and liabilities held at March 31The amount of total net losses for the period included in changes in net assets attributable to the change in unrealized losses relating to assets and liabilities held at March 31($4)($5)$—$—
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IPLIPLCommodity Contract DerivativeIPLCommodity Contract Derivative
Assets and (Liabilities), netDeferred ProceedsAssets and (Liabilities), netDeferred Proceeds
Three Months Ended March 31Three Months Ended March 312022202120222021Three Months Ended March 312023202220232022
Beginning balance, January 1Beginning balance, January 1$18$26$214$188Beginning balance, January 1$16$18$185$214
Total net losses included in changes in net assets (realized/unrealized)(4)(5)
Total net gains (losses) included in changes in net assets (realized/unrealized)Total net gains (losses) included in changes in net assets (realized/unrealized)1(4)
Settlements (a)Settlements (a)(7)(6)13(81)Settlements (a)(17)(7)(32)13
Ending balance, March 31Ending balance, March 31$7$15$227$107Ending balance, March 31$—$7$153$227
The amount of total net losses for the period included in changes in net liabilities attributable to the change in unrealized losses relating to liabilities held at March 31($4)($6)$—$—
The amount of total net gains (losses) for the period included in changes in net assets attributable to the change in unrealized gains (losses) relating to assets and liabilities held at March 31The amount of total net gains (losses) for the period included in changes in net assets attributable to the change in unrealized gains (losses) relating to assets and liabilities held at March 31$1($4)$—$—
WPLWPLCommodity Contract DerivativeWPLCommodity Contract Derivative
Assets and (Liabilities), netAssets and (Liabilities), net
Three Months Ended March 31Three Months Ended March 3120222021Three Months Ended March 3120232022
Beginning balance, January 1Beginning balance, January 1$11$3Beginning balance, January 1$3$11
Total net losses included in changes in net assets (realized/unrealized)Total net losses included in changes in net assets (realized/unrealized)(2)(1)Total net losses included in changes in net assets (realized/unrealized)(5)(2)
SettlementsSettlements(6)(1)Settlements(3)(6)
Ending balance, March 31Ending balance, March 31$3$1Ending balance, March 31($5)$3
The amount of total net losses for the period included in changes in net liabilities attributable to the change in unrealized losses relating to liabilities held at March 31($1)$—
The amount of total net losses for the period included in changes in net assets attributable to the change in unrealized losses relating to assets and liabilities held at March 31The amount of total net losses for the period included in changes in net assets attributable to the change in unrealized losses relating to assets and liabilities held at March 31($5)($1)
(a)Settlements related to deferred proceeds are due to the change in the carrying amount of receivables sold less the allowance for expected credit losses associated with the receivables sold and cash amounts received from the receivables sold.

Commodity Contracts - The fair value of FTR and natural gas commodity contracts categorized as Level 3 was recognized as net derivative assets (liabilities) as follows (in millions):
Alliant EnergyIPLWPL
Excluding FTRsFTRsExcluding FTRsFTRsExcluding FTRsFTRs
March 31, 2022$3$7$3$4$—$3
December 31, 2021920810110
Alliant EnergyIPLWPL
Excluding FTRsFTRsExcluding FTRsFTRsExcluding FTRsFTRs
March 31, 2023($10)$5($4)$4($6)$1
December 31, 2022(10)29(9)25(1)4

NOTE 12.13. COMMITMENTS AND CONTINGENCIES
NOTE 12(a)13(a) Capital Purchase Commitments - Various contractual obligations contain minimum future commitments related to capital expenditures for certain construction projects, including IPL’s and WPL’s expansion of solar generation. At March 31, 2022,2023, Alliant Energy’s, IPL’s and WPL’s minimum future commitments for these projects were $214$252 million, $40 million and $213$212 million, respectively.

NOTE 12(b)13(b) Other Purchase Commitments - Various commodity supply, transportation and storage contracts help meet obligations to provide electricity and natural gas to utility customers. In addition, there are various purchase commitments associated with other goods and services. At March 31, 2022,2023, related minimum future commitments were as follows (in millions):
Alliant EnergyIPLWPLAlliant EnergyIPLWPL
Natural gasNatural gas$939$472$467Natural gas$1,280$565$715
CoalCoal1277255Coal1758986
Other (a)Other (a)1356636Other (a)1135326
$1,201$610$558$1,568$707$827

(a)Includes individual commitments incurred during the normal course of business that exceeded $1 million at March 31, 2022.2023.

NOTE 12(c)13(c) Guarantees and Indemnifications -
Whiting Petroleum - Whiting Petroleum is an independent oil and gas company. In 2004, Alliant Energy sold its remaining interest in Whiting Petroleum. Alliant Energy Resources, LLC, as the successor to a predecessor entity that owned Whiting Petroleum, and a wholly-owned subsidiary of AEF, continues to guarantee the partnership obligations of an affiliate of Whiting Petroleum under multiple general partnership agreements in the oil and gas industry. The guarantees do not include a maximum limit. Based on information made available to Alliant Energy by Whiting Petroleum, the Whiting Petroleum affiliate holds an approximate 6% share in the partnerships, and currently known obligations include costs associated with the future
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abandonment of certain facilities owned by the partnerships. The general partnerships were formed under California law, and Alliant Energy Resources, LLC may need to perform under the guarantees if the affiliate of Whiting Petroleum is unable to meet its partnership obligations.
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As of March 31, 2022,2023, the currently known partnership obligations for the abandonment obligations are estimated at $60$58 million, which represents Alliant Energy’s currently estimated maximum exposure under the guarantees. Alliant Energy estimates its expected loss to be a portion of the $60$58 million of known partnership abandonment obligations of the Whiting Petroleum affiliate and the other partners. Alliant Energy is not aware of any material liabilities related to these guarantees that it is probable that it will be obligated to pay; however, as of both March 31, 20222023 and December 31, 2021,2022, a liability of $5 million is recorded in “Other liabilities” on Alliant Energy’s balance sheets for expected credit losses related to the contingent obligations that are in the scope of these guarantees.

Whiting Petroleum completed a business combination with Oasis Petroleum Inc. in July 2022. The combined operations are now known as Chord Energy Corporation. The business combination is not expected to affect the scope of the Whiting Petroleum affiliate’s obligations to Alliant Energy or Alliant Energy’s related guarantees.

Non-utility Wind Farm in Oklahoma - In 2017, a wholly-owned subsidiary of AEF acquired a cash equity ownership interest in a non-utility wind farm located in Oklahoma. The wind farm provides electricity to a third party under a long-term PPA. Alliant Energy provided a parent guarantee of its subsidiary’s indemnification obligations under the related operating agreement and PPA. Alliant Energy’s obligations under the operating agreement were $67$59 million as of March 31, 20222023 and will reduce annually until expiring in July 2047. Alliant Energy’s obligations under the PPA are subject to a maximum limit of $17 million and expire in December 2031, subject to potential extension. Alliant Energy is not aware of any material liabilities related to this guarantee that it is probable that it will be obligated to pay and therefore has not recognized any material liabilities related to this guarantee as of March 31, 20222023 and December 31, 2021.2022.

NOTE 12(d)13(d) Environmental Matters -
Manufactured Gas Plant (MGP) Sites - IPL and WPL have current or previous ownership interests in various sites that are previously associated with the production of gas for which IPL and WPL have, or may have in the future, liability for investigation, remediation and monitoring costs. IPL and WPL are working pursuant to the requirements of various federal and state agencies to investigate, mitigate, prevent and remediate, where necessary, the environmental impacts to property, including natural resources, at and around these former MGP sites in order to protect public health and the environment. At March 31, 2022,2023, estimated future costs expected to be incurred for the investigation, remediation and monitoring of the MGP sites, as well as environmental liabilities recorded on the balance sheets for these sites, which are not discounted, were as follows (in millions). At March 31, 2022, such amounts for WPL were not material.:
Alliant EnergyIPLAlliant EnergyIPLWPL
Range of estimated future costsRange of estimated future costs$10 -$26$7 -$20Range of estimated future costs$10 -$37$6 -$12$4 -$25
Current and non-current environmental liabilitiesCurrent and non-current environmental liabilities$12$9Current and non-current environmental liabilities$18$8$10

IPL Consent Decree - In 2015, the U.S. District Court for the Northern District of Iowa approved a Consent Decree that IPL entered into with the EPA, the Sierra Club, the State of Iowa and Linn County in Iowa, thereby resolving potential Clean Air Act issues associated with emissions from IPL’s coal-fired generating facilities in Iowa. IPL has completed various requirements under the Consent Decree. IPL’s remaining requirements include fuel switching or retiring Prairie Creek Units 1 and 3 by December 31, 2025. Alliant Energy and IPL currently expect to recover material costs incurred by IPL related to compliance with the terms of the Consent Decree from IPL’s electric customers.

Other Environmental Contingencies - In addition to the environmental liabilities discussed above, various environmental rules are monitored that may have a significant impact on future operations. Several of these environmental rules are subject to legal challenges, reconsideration and/or other uncertainties. Given uncertainties regarding the outcome, timing and compliance plans for these environmental matters, the complete financial impact of each of these rules is not able to be determined; however, future capital investments and/or modifications to EGUs and electric and gas distribution systems to comply with certain of these rules could be significant. Specific current, proposed or potential environmental matters include, among others: Cross-State Air Pollution Rule, Effluent Limitation Guidelines, Coal Combustion Residuals Rule, and various legislation and EPA regulations to monitor and regulate the emission of greenhouse gases, including the Clean Air Act.

NOTE 12(e) Collective Bargaining Agreements13(e) MISO Transmission Owner Return on Equity Complaints - At March 31,A group of stakeholders, including MISO cooperative and municipal utilities, previously filed complaints with the Federal Energy Regulatory Commission (FERC) requesting a reduction to the base return on equity authorized for MISO transmission owners, including ITC Midwest LLC and ATC. In 2019, FERC issued an order on the previously filed complaints and reduced the base return on equity authorized for the MISO transmission owners to 9.88% for November 12, 2013 through February 11, 2015, and subsequent to September 28, 2016. In 2020, FERC issued orders in response to various rehearing requests and increased the base return on equity authorized for the MISO transmission owners from 9.88% to 10.02% for November 12, 2013 through February 11, 2015, and subsequent to September 28, 2016. In August 2022, employees covered by collective bargaining agreements represented 55%, 70%the U.S. Court of Appeals for the District of Columbia Circuit vacated FERC’s prior orders that established the base return on equity authorized for the MISO transmission owners and 83% of total employees of Alliant Energy, IPL and WPL, respectively. In May 2022, WPL’s collective bargaining agreement with International Brotherhood of Electrical Workers Local 965 expires, representing 26% and 83% of total employees of Alliant Energy and WPL, respectively. Whileremanded the processcases to renewFERC for further proceedings, which may result in additional changes to the agreement is underway and a tentative agreement has been reached, Alliant Energy and WPL are currently unable to predict the outcome.

base return on equity authorized for
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the MISO transmission owners. Any further changes in FERC’s decisions may have an impact on Alliant Energy’s share of ATC’s future earnings and customer costs.

NOTE 13.14. SEGMENTS OF BUSINESS
Certain financial information relating to Alliant Energy’s, IPL’s and WPL’s business segments is as follows. Intersegment revenues were not material to their respective operations.
Alliant EnergyAlliant EnergyATC Holdings,AlliantAlliant EnergyATC Holdings,Alliant
UtilityNon-Utility,EnergyUtilityNon-Utility,Energy
ElectricGasOtherTotalParent and OtherConsolidatedElectricGasOtherTotalParent and OtherConsolidated
(in millions)(in millions)
Three Months Ended March 31, 2023Three Months Ended March 31, 2023
RevenuesRevenues$768$276$11$1,055$22$1,077
Operating incomeOperating income1635042175222
Net income attributable to Alliant Energy common shareownersNet income attributable to Alliant Energy common shareowners1603163
Three Months Ended March 31, 2022Three Months Ended March 31, 2022Three Months Ended March 31, 2022
RevenuesRevenues$773$262$11$1,046$22$1,068Revenues$773$262$11$1,046$22$1,068
Operating incomeOperating income1815732417248Operating income1815732417248
Net income attributable to Alliant Energy common shareownersNet income attributable to Alliant Energy common shareowners17913192Net income attributable to Alliant Energy common shareowners17913192
Three Months Ended March 31, 2021
Revenues$701$170$13$884$17$901
Operating income1474421935198
Net income attributable to Alliant Energy common shareowners1638171
IPLIPLElectricGasOtherTotalIPLElectricGasOtherTotal
(in millions)(in millions)
Three Months Ended March 31, 2023Three Months Ended March 31, 2023
RevenuesRevenues$388$150$11$549
Operating incomeOperating income6627396
Net incomeNet income72
Three Months Ended March 31, 2022Three Months Ended March 31, 2022Three Months Ended March 31, 2022
RevenuesRevenues$400$139$11$550Revenues$400$139$11$550
Operating incomeOperating income75323110Operating income75323110
Net income available for common stock87
Three Months Ended March 31, 2021
Revenues$386$91$12$489
Operating income72301103
Net income available for common stock79
Net incomeNet income87
WPLWPLElectricGasOtherTotalWPLElectricGasOtherTotal
(in millions)(in millions)
Three Months Ended March 31, 2022
Three Months Ended March 31, 2023Three Months Ended March 31, 2023
RevenuesRevenues$373$123$—$496Revenues$380$126$—$506
Operating incomeOperating income10625131Operating income97231121
Net incomeNet income92Net income88
Three Months Ended March 31, 2021
Three Months Ended March 31, 2022Three Months Ended March 31, 2022
RevenuesRevenues$315$79$1$395Revenues$373$123$—$496
Operating incomeOperating income7514190Operating income10625131
Net incomeNet income84Net income92

NOTE 14.15. RELATED PARTIES
Service Agreements - Pursuant to service agreements, IPL and WPL receive various administrative and general services from an affiliate, Corporate Services. These services are billed to IPL and WPL at cost based on expenses incurred by Corporate Services for the benefit of IPL and WPL, respectively. These costs consisted primarily of employee compensation and benefits, fees associated with various professional services, depreciation and amortization of property, plant and equipment, and a return on net assets. Corporate Services also acts as agent on behalf of IPL and WPL pursuant to the service agreements. As agent, Corporate Services enters into energy, capacity, ancillary services, and transmission sale and purchase transactions within MISO. Corporate Services assigns such sales and purchases among IPL and WPL based on statements received from MISO. The amounts billed for services provided, sales credited and purchases for the three months ended March 31 were as follows (in millions):
IPLWPLIPLWPL
20222021202220212023202220232022
Corporate Services billingsCorporate Services billings$40$40$36$35Corporate Services billings$40$40$36$36
Sales creditedSales credited1181Sales credited71318
Purchases billedPurchases billed941432226Purchases billed93941522

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Net intercompany payables to Corporate Services were as follows (in millions):
IPLWPL
March 31, 2022December 31, 2021March 31, 2022December 31, 2021
Net payables to Corporate Services$120$110$76$83
IPLWPL
March 31, 2023December 31, 2022March 31, 2023December 31, 2022
Net payables to Corporate Services$110$103$65$56

ATC - Pursuant to various agreements, WPL receives a range of transmission services from ATC. WPL provides operation, maintenance, and construction services to ATC. WPL and ATC also bill each other for use of shared facilities owned by each party. The related amounts billed between the parties for the three months ended March 31 were as follows (in millions):

2022202120232022
ATC billings to WPLATC billings to WPL$34$32ATC billings to WPL$34$34
WPL billings to ATCWPL billings to ATC33WPL billings to ATC63

WPL owed ATC net amounts of $9 million as of March 31, 20222023 and $10 million as of December 31, 2021.2022.

ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

This MDA includes information relating to Alliant Energy, and IPL and WPL (collectively, the Utilities), as well as ATC Holdings, AEF and Corporate Services. Where appropriate, information relating to a specific entity has been segregated and labeled as such. The following discussion and analysis should be read in conjunction with the Financial Statements and the Notes included in this report, as well as the financial statements, notes and MDA included in the 20212022 Form 10-K. Unless otherwise noted, all “per share” references in MDA refer to earnings per diluted share.

20222023 HIGHLIGHTS

Key highlights since the filing of the 20212022 Form 10-K include the following:

Customer Investments:
In responseMarch 2023, the IUB issued a certificate of public convenience, use and necessity (GCU Certificate) granting IPL approval to a petition from a U.S.-based solar panel assembler, in March 2022, the U.S. Department of Commerce initiated an investigation into whether the sourcingconstruct, own and operate up to 50 MW of solar project materialsgeneration and equipment from certain Southeast Asian countries circumvent tariffs and duties imposed on such materials and equipment imported from China. Alliant Energy, IPL and WPL are currently unableup to predict with certainty the future outcome or impact25 MW of these matters; however, this could resultbattery storage in delays and/or higher costs for IPL’s and WPL’s planned development and acquisition of additional renewable energy, and impact Alliant Energy’s, IPL’s and WPL’s anticipated future construction and acquisition expenditures.Union County, Iowa.
In April 2022,2023, the IUB issued an order approving IPL’s requesta GCU Certificate granting IPL approval to construct, own and operate up to 150 MW of solar generation and up to 75 MW of battery storage in Lee County, Iowa.
In 2021, IPL filed for an extension of the procedural schedule related to its November 2021 advance rate-making principles filing with the IUB for up to 400 MW of new solar generation and 75 MW of battery storage. IPL requested an extensionOn April 27, 2023, the IUB approved advance rate-making principles for up to 200 MW of solar generation. The IUB’s order included a cost target of $1,575/kilowatt, including AFUDC and transmission upgrade costs among other costs. Any reasonable and prudent costs incurred in order to review the proposed fixed cost cap included in its November 2021 filing givenexcess of the cost pressures prevalent in the solar generation and battery storage markets,target, as well as narrow the selectionrelated return on common equity, would need to be addressed in future IPL retail electric rate review filings. IPL has 20 days from the date of certain solar generation projects included in the filing. IPL currently expects a decision on itsIUB’s order to ask for reconsideration of the advance rate-making principles, filing byand 30 days from the enddate of 2022.the IUB’s order to accept the approved advance rate-making principles.

Rate Matters:
In April 2022,2023, WPL receivedfiled a retail electric and gas rate review with the PSCW for the 2024/2025 forward-looking Test Period. The key drivers for the filing include revenue requirement impacts of increasing electric and gas rate base, including investments in solar generation and battery storage. The filing requested approval for WPL to implement increases in annual rates for its retail electric and gas customers of $111 million and $17 million in 2024, respectively, with any granted rate changes expected to be effective on January 1, 2024. WPL’s filing also requested approval to implement an oraladditional $71 million increase in annual rates for its retail electric customers in 2025, with any granted rate changes expected to be effective on January 1, 2025. WPL also requested to maintain its current authorized return on common equity of 10% and implement an approximate 56% common equity component of its regulatory capital structure, as well as receive continued recovery of and a return on the remaining net book value of Edgewater Unit 5, which is currently expected to be retired by June 1, 2025. A decision from the PSCW for its second certificateis expected by the end of authority authorizing WPL to acquire, construct, own, and operate up to 414 MW of new solar generation in the following Wisconsin counties: Dodge (150 MW), Waushara (99 MW), Rock (65 MW), Grant (50 MW) and Green (50 MW).

Legislative Matters:
Refer to Note 8 for discussion of Iowa tax reform enacted in March 2022.2023.

RESULTS OF OPERATIONS

Results of operations include financial information prepared in accordance with GAAP as well as utility electric margins and utility gas margins, which are not measures of financial performance under GAAP. Utility electric margins are defined as electric revenues less electric production fuel, purchased power and electric transmission service expenses. Utility gas margins are defined as gas revenues less cost of gas sold. Utility electric margins and utility gas margins are non-GAAP financial measures because they exclude other utility and non-utility revenues, other operation and maintenance expenses, depreciation and amortization expenses, and taxes other than income tax expense.

Management believes that utility electric and gas margins provide a meaningful basis for evaluating and managing utility operations since electric production fuel, purchased power and electric transmission service expenses and cost of gas sold are
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generally passed through to customers, and therefore, result in changes to electric and gas revenues that are comparable to changes in such expenses. The presentation of utility electric and gas margins herein is intended to provide supplemental information for investors regarding operating performance. These utility electric and gas margins may not be comparable to how other entities define utility electric and gas margin. Furthermore, these measures are not intended to replace operating income as determined in accordance with GAAP as an indicator of operating performance.
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Additionally, the table below includes EPS for Utilities and Corporate Services, ATC Holdings, and Non-utility and Parent, which are non-GAAP financial measures. Alliant Energy believes these non-GAAP financial measures are useful to investors because they facilitate an understanding of segment performance and trends, and provide additional information about Alliant Energy’s operations on a basis consistent with the measures that management uses to manage its operations and evaluate its performance.

Financial Results Overview - Alliant Energy’s net income and EPS attributable to Alliant Energy common shareowners for the three months ended March 31 were as follows (dollars in millions, except per share amounts):
2022202120232022
IncomeEPSIncome (Loss)EPSIncome (Loss)EPSIncomeEPS
Utilities and Corporate ServicesUtilities and Corporate Services$183$0.73$166$0.66Utilities and Corporate Services$163$0.65$183$0.73
ATC HoldingsATC Holdings80.0380.03ATC Holdings90.0480.03
Non-utility and ParentNon-utility and Parent10.01(3)(0.01)Non-utility and Parent(9)(0.04)10.01
Alliant Energy ConsolidatedAlliant Energy Consolidated$192$0.77$171$0.68Alliant Energy Consolidated$163$0.65$192$0.77

Alliant Energy’s Utilities and Corporate Services net income increaseddecreased by $17$20 million for the three-month period, primarily due to lower retail electric and gas sales due to impacts of warmer than normal temperatures on customer demand in the first quarter of 2023, compared to an increase in sales in the first quarter of 2022 due to impacts of colder than normal temperatures on customer demand, higher interest expense and timing of income tax expense. These items were partially offset by higher electric revenues resulting from higher revenue requirements and AFUDC from WPL’s capital investments.

Alliant Energy’s Non-utility and Parent net income decreased by $10 million for the three-month period, primarily due to higher AFUDC, higher earnings resulting from WPL’s increasing rate base, higher sales due to favorable temperature impacts compared to 2021, as well as higher temperature-normalized sales.interest expense.

For the three months ended March 31, operating income and a reconciliation of utility electric and gas margins to the most directly comparable GAAP measure, operating income, was as follows (in millions):
Alliant EnergyIPLWPLAlliant EnergyIPLWPL
Three MonthsThree Months202220212022202120222021Three Months202320222023202220232022
Operating incomeOperating income$248$198$110$103$131$90Operating income$222$248$96$110$121$131
Electric utility revenuesElectric utility revenues$773$701$400$386$373$315Electric utility revenues$768$773$388$400$380$373
Electric production fuel and purchased power expensesElectric production fuel and purchased power expenses(168)(133)(67)(59)(101)(74)Electric production fuel and purchased power expenses(157)(168)(47)(67)(109)(101)
Electric transmission service expenseElectric transmission service expense(138)(134)(97)(92)(41)(42)Electric transmission service expense(146)(138)(104)(97)(42)(41)
Utility Electric Margin (non-GAAP)Utility Electric Margin (non-GAAP)467434236235231199Utility Electric Margin (non-GAAP)465467237236229231
Gas utility revenuesGas utility revenues2621701399112379Gas utility revenues276262150139126123
Cost of gas soldCost of gas sold(168)(100)(85)(50)(83)(50)Cost of gas sold(181)(168)(95)(85)(86)(83)
Utility Gas Margin (non-GAAP)Utility Gas Margin (non-GAAP)947054414029Utility Gas Margin (non-GAAP)959455544040
Other utility revenuesOther utility revenues111311121Other utility revenues11111111
Non-utility revenuesNon-utility revenues2217Non-utility revenues2222
Other operation and maintenance expensesOther operation and maintenance expenses(153)(146)(83)(77)(58)(59)Other operation and maintenance expenses(174)(153)(95)(83)(66)(58)
Depreciation and amortization expensesDepreciation and amortization expenses(166)(164)(94)(94)(70)(69)Depreciation and amortization expenses(166)(166)(96)(94)(68)(70)
Taxes other than income tax expenseTaxes other than income tax expense(27)(26)(14)(14)(12)(11)Taxes other than income tax expense(31)(27)(16)(14)(14)(12)
Operating incomeOperating income$248$198$110$103$131$90Operating income$222$248$96$110$121$131
Operating Income Variances - Variances between periods in operating income for the three months ended March 31, 20222023 compared to the same period in 20212022 were as follows (in millions):
Alliant EnergyIPLWPL
Total higher utility electric margin variance (Refer to details below)$33$1$32
Total higher utility gas margin variance (Refer to details below)241311
Total (higher) lower other operation and maintenance expenses variance (Refer to details below)(7)(6)1
Higher depreciation and amortization expense primarily due to additional plant in service in 2021 and 2022(2)(1)
Other2(1)(2)
$50$7$41
Alliant EnergyIPLWPL
Total higher (lower) utility electric margin variance (Refer to details below)($2)$1($2)
Total higher utility gas margin variance (Refer to details below)11
Total higher other operation and maintenance expenses variance (Refer to details below)(21)(12)(8)
Total (higher) lower depreciation and amortization expense(2)2
Other(4)(2)(2)
($26)($14)($10)
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Electric and Gas Revenues and Sales Summary - Electric and gas revenues (in millions), and MWh and Dth sales (in thousands), for the three months ended March 31 were as follows:
Alliant EnergyAlliant EnergyElectricGasAlliant EnergyElectricGas
RevenuesMWhs SoldRevenuesDths SoldRevenuesMWhs SoldRevenuesDths Sold
2022202120222021202220212022202120232022202320222023202220232022
RetailRetail$692$6366,3886,272$248$15726,09523,431Retail$686$6926,2016,388$262$24822,31026,095
Sales for resale68451,9451,071N/AN/AN/AN/A
Sales for resale:Sales for resale:
WholesaleWholesale4647698721N/AN/AN/AN/A
Bulk power and otherBulk power and other23211,2431,224N/AN/AN/AN/A
Transportation/OtherTransportation/Other13201719141329,87724,690Transportation/Other13131517141432,61429,877
$773$7018,3507,362$262$17055,97248,121$768$7738,1578,350$276$26254,92455,972
IPLElectricGas
RevenuesMWhs SoldRevenuesDths Sold
20232022202320222023202220232022
Retail$362$3793,5443,651$141$13011,45913,601
Sales for resale:
Wholesale1215187194N/AN/AN/AN/A
Bulk power and other7(2)496403N/AN/AN/AN/A
Transportation/Other78889912,03512,020
$388$4004,2354,256$150$13923,49425,621
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IPLElectricGas
RevenuesMWhs SoldRevenuesDths Sold
20222021202220212022202120222021
Retail$379$3613,6513,582$130$8213,60112,138
Sales for resale1311597287N/AN/AN/AN/A
Transportation/Other8148109912,02011,178
$400$3864,2563,879$139$9125,62123,316
WPLWPLElectricGasWPLElectricGas
RevenuesMWhs SoldRevenuesDths SoldRevenuesMWhs SoldRevenuesDths Sold
2022202120222021202220212022202120232022202320222023202220232022
RetailRetail$313$2752,7372,690$118$7512,49411,293Retail$324$3132,6572,737$121$11810,85112,494
Sales for resale55341,348784N/AN/AN/AN/A
Sales for resale:Sales for resale:
WholesaleWholesale3432511527N/AN/AN/AN/A
Bulk power and otherBulk power and other1623747821N/AN/AN/AN/A
Transportation/OtherTransportation/Other56995417,85713,512Transportation/Other65795520,57917,857
$373$3154,0943,483$123$7930,35124,805$380$3733,9224,094$126$12331,43030,351

Sales Trends and Temperatures - Alliant Energy’s retail electric and gas sales volumes increased 2%decreased 3% and 11%15%, respectively, for the three months ended March 31, 20222023 compared to the same period in 2021,2022, primarily due to changes in temperatures, COVID-19 impacts in 2021 and increases in the number of customers.temperatures.

Estimated increases (decreases) to electric and gas margins from the impacts of temperatures for the three months ended March 31 were as follows (in millions):
Electric MarginsGas MarginsElectric MarginsGas Margins
20222021Change20222021Change20232022Change20232022Change
IPLIPL$5$2$3$3$2$1IPL($4)$5($9)($3)$3($6)
WPLWPL21111WPL(5)2(7)(3)1(4)
Total Alliant EnergyTotal Alliant Energy$7$3$4$4$2$2Total Alliant Energy($9)$7($16)($6)$4($10)

Electric Sales for Resale - Electric sales for resale volume changes were largely due to changes in sales in the wholesale energy markets operated by MISO. These changes are impacted by several factors, including the availability and dispatch of Alliant Energy’s EGUs and electricity demand within these wholesale energy markets. Changes in sales for resale revenues were largely offset by changes in fuel-related costs, and therefore, did not have a significant impact on electric margins.

Gas Transportation/Other - Gas transportation/other sales volume changes were largely due to changes in the gas volumes supplied to Alliant Energy’s natural gas-fired EGUs caused by the availability and dispatch of such EGUs. Changes in these transportation/other revenues did not have a significant impact on gas margins.

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Utility Electric Margin Variances - The following items contributed to increased (decreased) utility electric margins for the three months ended March 31, 20222023 compared to the same period in 20212022 as follows (in millions):
Alliant EnergyIPLWPL
Higher revenue requirements at WPL due to increasing rate base (a)$26$—$26
Higher revenues at IPL due to changes in credits on customers’ bills related to excess deferred income tax benefits amortization through the tax benefit rider (offset by changes in income tax)66
Estimated changes in sales volumes caused by temperatures431
Lower revenues at IPL due to changes in the renewable energy rider (offset by changes in income tax)(12)(12)
Lower revenues at IPL related to changes in recovery amounts for energy efficiency costs through the energy efficiency rider (mostly offset by changes in energy efficiency expense)(2)(2)
Other (includes higher temperature-normalized sales in 2022)1165
$33$1$32
Alliant EnergyIPLWPL
Estimated changes in sales volumes caused by temperatures($16)($9)($7)
Higher revenues at IPL due to changes in the renewable energy rider (mostly offset by changes in income taxes)77
Other735
($2)$1($2)

(a)In December 2021, the PSCW issued an order authorizing annual base rate increases of $114 million and $15 million for WPL’s retail electric and gas customers, respectively, covering the 2022/2023 forward-looking Test Period, which was based on a stipulated agreement between WPL and certain stakeholders. The key drivers for the annual base rate increases include higher retail fuel-related costs in 2022, lower excess deferred income tax benefits in 2022 and 2023 compared to 2021, and revenue requirement impacts of increasing electric and gas rate base, including investments in solar generation. Retail electric rate changes were effective on January 1, 2022 and extend through the end of 2023. Retail gas rate changes were effective on January 1, 2022 and extend through the end of 2022. The higher fuel expense costs are recognized in electric margin and the lower amount of excess deferred income tax benefits is recognized as a reduction in income tax.

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Utility Gas Margin Variances - The following items contributed to increased (decreased) utility gas margins for the three months ended March 31, 20222023 compared to the same period in 20212022 as follows (in millions):
Alliant EnergyIPLWPLAlliant EnergyIPLWPL
Higher revenues at IPL related to changes in recovery amounts for energy efficiency costs through the energy efficiency rider (mostly offset by changes in energy efficiency expense)Higher revenues at IPL related to changes in recovery amounts for energy efficiency costs through the energy efficiency rider (mostly offset by changes in energy efficiency expense)$9$9$—Higher revenues at IPL related to changes in recovery amounts for energy efficiency costs through the energy efficiency rider (mostly offset by changes in energy efficiency expense)$6$6$—
Higher revenue requirements at WPL due to increasing rate base (refer to (a) above)77
Higher revenue requirements at WPL (a)Higher revenue requirements at WPL (a)44
Estimated changes in sales volumes caused by temperaturesEstimated changes in sales volumes caused by temperatures211Estimated changes in sales volumes caused by temperatures(10)(6)(4)
Other (includes higher temperature-normalized sales in 2022)633
OtherOther11
$24$13$11$1$1$—

(a)In December 2022, the PSCW issued an order authorizing an annual base rate increase of $9 million for WPL’s retail gas customers, covering the 2023 forward-looking Test Period, which reflects changes in weighted average cost of capital, updated depreciation rates and modifications to certain regulatory asset and regulatory liability amortizations. These retail gas rate changes were effective on January 1, 2023 and extend through the end of 2023.

Other Operation and Maintenance Expenses Variances - The following items contributed to (increased) decreased other operation and maintenance expenses for the three months ended March 31, 20222023 compared to the same period in 20212022 as follows (in millions):
Alliant EnergyIPLWPLAlliant EnergyIPLWPL
Higher energy efficiency expense at IPL (mostly offset by higher revenues)Higher energy efficiency expense at IPL (mostly offset by higher revenues)($6)($6)$—
Higher energy efficiency expense at IPL (primarily offset by higher revenues)($9)($9)$—
Higher generation operation and maintenance expensesHigher generation operation and maintenance expenses(5)2(7)
OtherOther231Other(10)(8)(1)
($7)($6)$1($21)($12)($8)

Other Income and Deductions Variances - The following items contributed to (increased) decreased other income and deductions for the three months ended March 31, 20222023 compared to the same period in 20212022 as follows (in millions):
Alliant EnergyIPLWPLAlliant EnergyIPLWPL
Higher interest expense primarily due to financings completed in 2021($5)($2)($1)
Higher interest expense primarily due to financings completed in 2023 and 2022, and higher interest ratesHigher interest expense primarily due to financings completed in 2023 and 2022, and higher interest rates($20)$—($9)
Higher AFUDC primarily due to changes in construction work in progress balances related to WPL’s solar generationHigher AFUDC primarily due to changes in construction work in progress balances related to WPL’s solar generation717Higher AFUDC primarily due to changes in construction work in progress balances related to WPL’s solar generation87
OtherOther21Other(1)(1)(1)
$4($1)$7($13)($1)($3)

Income Taxes - Refer to Note8 9 for details of effective income tax rates.

Preferred Dividend Requirements of IPL - Alliant Energy’s and IPL’s preferred dividend requirements decreased for the three months ended March 31, 2022 compared to the same period in 2021 a due to the redemption of IPL’s 5.1% cumulative preferred stock in December 2021.

LIQUIDITY AND CAPITAL RESOURCES

The liquidity and capital resources summary included in the 20212022 Form 10-K has not changed materially, except as described below.

Liquidity Position - At March 31, 2022,2023, Alliant Energy had $67$157 million of cash and cash equivalents, $724$940 million ($331450 million at the parent company, $250 million at IPL and $143$240 million at WPL) of available capacity under the single revolving credit facility and $109$21 million of available capacity at IPL under its sales of accounts receivable program.

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Capital Structure - Capital structures at March 31, 20222023 were as follows (Long-term Debt (including current maturities) (LD); Short-term Debt (SD); Common Equity (CE)):
lnt-20220331_g2.jpglnt-20220331_g3.jpglnt-20220331_g4.jpg
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636637638
Cash Flows - Selected information from the cash flows statements was as follows (in millions):
Alliant EnergyIPLWPLAlliant EnergyIPLWPL
202220212022202120222021202320222023202220232022
Cash, cash equivalents and restricted cash, January 1Cash, cash equivalents and restricted cash, January 1$40$56$34$50$2$3Cash, cash equivalents and restricted cash, January 1$24$40$15$34$5$2
Cash flows from (used for):Cash flows from (used for):Cash flows from (used for):
Operating activitiesOperating activities25114589(45)167148Operating activities1882512489185167
Investing activitiesInvesting activities(223)(38)1898(217)(119)Investing activities(263)(223)7018(295)(217)
Financing activitiesFinancing activities3(145)(79)(92)52(30)Financing activities2123(74)(79)19152
Net increase (decrease)31(38)28(39)2(1)
Net increaseNet increase137312028812
Cash, cash equivalents and restricted cash, March 31Cash, cash equivalents and restricted cash, March 31$71$18$62$11$4$2Cash, cash equivalents and restricted cash, March 31$161$71$35$62$86$4

Operating Activities - The following items contributed to increased (decreased) operating activity cash flows for the three months ended March 31, 20222023 compared to the same period in 20212022 (in millions):
Alliant EnergyIPLWPL
Higher collections from WPL’s increasing base rate$33$—$33
Natural gas cost payments from extreme temperatures in February 2021 resulting in under-recovered natural gas costs at IPL in 20212020
Increased collections from IPL’s and WPL’s retail customers caused by temperature impacts on electric and gas sales642
Changes in interest payments(3)(2)
Changes in income taxes paid/refunded(7)
Timing of intercompany payments and receipts6016
Other (primarily due to other changes in working capital)5057(30)
$106$134$19
Alliant EnergyIPLWPL
Changes in interest payments($31)$—($17)
Decreased collections from IPL’s and WPL’s retail customers caused by temperature impacts on electric and gas sales(26)(15)(11)
Changes in the sales of accounts receivable at IPL(13)(13)
Timing of intercompany payments and receipts(5)14
Other (primarily due to other changes in working capital)7(32)32
($63)($65)$18

Investing Activities - The following items contributed to increased (decreased) investing activity cash flows for the three months ended March 31, 20222023 compared to the same period in 20212022 (in millions):
Alliant EnergyIPLWPLAlliant EnergyIPLWPL
Higher utility construction and acquisition expenditures (a)Higher utility construction and acquisition expenditures (a)($110)($5)($104)
Changes in the amount of cash receipts on sold receivablesChanges in the amount of cash receipts on sold receivables($94)($94)$—Changes in the amount of cash receipts on sold receivables5858
(Higher) lower utility construction and acquisition expenditures (a)(93)10(104)
Proceeds from sale of partial ownership interest in West RiversideProceeds from sale of partial ownership interest in West Riverside2525
OtherOther246Other(13)(1)1
($185)($80)($98)($40)$52($78)

(a)Largely due to higher expenditures for WPL’s solar generation, partially offset by lower expenditures for IPL’s and WPL’s electric and gas distribution systems.generation.

Construction and Acquisition Expenditures - Alliant Energy, IPLIn March 2023, WPL notified the PSCW that it currently expects estimated construction costs and WPLrelated rate base additions associated with its 414 MW of new solar generation will exceed amounts approved by the PSCW in June 2022 by approximately 10-14% due to higher commodity, labor and other site-specific costs. A significant portion of these higher estimated construction costs are currently evaluating potential impacts from cost pressures prevalentincluded in the solar generation and battery storage markets, as well as the U.S. Department of Commerce investigation discussed in “2022 Highlights,” on the timing and estimated costs for IPL’s and WPL’s planned development and acquisition of additional renewable energy, which could impact their anticipated future construction and acquisition expenditures.expenditures included in “Liquidity and Capital Resources” in the 2022 Form 10-K.

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Financing Activities - The following items contributed to increased (decreased) financing activity cash flows for the three months ended March 31, 20222023 compared to the same period in 20212022 (in millions):
Alliant EnergyIPLWPL
Higher net proceeds from issuance of long-term debt$650$—$—
Higher payments to retire long-term debt(300)
Net changes in the amount of commercial paper outstanding(186)30
(Higher) lower common stock dividends(5)20(2)
Higher capital contributions from WPL’s parent company, Alliant Energy55
Other(11)(7)(1)
$148$13$82
Alliant EnergyIPLWPL
Lower payments to retire long-term debt$300$—$—
Higher net proceeds from issuance of long-term debt212297
Net changes in the amount of commercial paper and other short-term borrowings outstanding(293)(151)
Other(10)5(7)
$209$5$139

IPL and WPL Solar Project Tax EquityState Regulatory Financing Authorization - Alliant Energy, IPL andIn March 2023, WPL are currently evaluating potential impactsreceived authorization from cost pressures prevalent in the solar generation and battery storage markets, as well asPSCW to have up to $500 million of short-term borrowings and/or letters of credit outstanding at any time through the U.S. Departmentexpiration date of Commerce investigation discussed in “2022 Highlights,” on the timing and estimated costs for IPL’s and WPL’s planned development and acquisition of additional renewable energy, which could result in changes to their proposed solar project tax equity financing.credit facility agreement.

Common Stock Issuances - Refer to Note 56 for discussion of common stock issuances by Alliant Energy in 2022.2023.

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Short-term Debt - Refer to TableNote 7(a) for discussion of ContentsAlliant Energy’s, IPL’s and WPL’s single credit facility agreement that was amended and extended in March 2023, which includes a revised cross-default provision related to prepayment of material debt prior to the stated maturity and certain other confirming changes, as well as details for proceeds from AEF’s December 2022 term loan credit agreement.

Long-term Debt - Refer to Note 67(b) for discussion of AEF’sAlliant Energy’s and WPL’s issuance of long-term debt in 2022. AEF’s current2023.

Interest Rate Risk - As of March 31, 2023, Alliant Energy’s exposure to risk resulting from changes in interest rates associated with variable-rate borrowings was mitigated primarily due to its issuance of convertible senior notes and an interest rate swap on a portion of its variable-rate term loan credit agreement that expiresborrowings, as well as WPL’s issuance of green bonds, all of which were executed in the first quarter of 2023. Assuming the impact of a hypothetical 100 basis point increase in interest rates on variable-rate borrowings and cash amounts outstanding under IPL’s sales of accounts receivable program at March 2024 includes an option to increase the amount outstanding up to $400 million in aggregate with the same maturity, subject to bank approval, and includes substantially the same financial covenants that are included in31, 2023, Alliant Energy’s credit facility agreement.annual pre-tax expense would increase by approximately $3 million.

Off-Balance Sheet Arrangements and Certain Financial Commitments - A summary of Alliant Energy’s and IPL’s off-balance sheet arrangements and Alliant Energy’s, IPL’s and WPL’s contractual obligations is included in the 20212022 Form 10-K and has not changed materially from the items reported in the 20212022 Form 10-K, except for the items described in Notes 34, 67 and 123.

ITEM 3. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

Quantitative and Qualitative Disclosures About Market Risk are reported in the 20212022 Form 10-K and have not changed materially.

ITEM 4. CONTROLS AND PROCEDURES

Alliant Energy’s, IPL’s and WPL’s management evaluated, with the participation of each of Alliant Energy’s, IPL’s and WPL’s Chief Executive Officer, Chief Financial Officer and Disclosure Committee, the effectiveness of the design and operation of Alliant Energy’s, IPL’s and WPL’s disclosure controls and procedures (as defined in Rule 13a-15(e) of the Securities Exchange Act of 1934)1934, as amended) as of March 31, 20222023 pursuant to the requirements of the Securities Exchange Act of 1934, as amended. Based on their evaluation, the Chief Executive OfficerOfficers and the Chief Financial Officer concluded that Alliant Energy’s, IPL’s and WPL’s disclosure controls and procedures were effective as of the quarter ended March 31, 2022.2023.

There was no change in Alliant Energy’s, IPL’s and WPL’s internal control over financial reporting that occurred during the quarter ended March 31, 20222023 that has materially affected, or is reasonably likely to materially affect, Alliant Energy’s, IPL’s or WPL’s internal control over financial reporting.

PART II. OTHER INFORMATION

ITEM 1. LEGAL PROCEEDINGS

None. SEC regulations require Alliant Energy, IPL and WPL to disclose information about certain proceedings arising under federal, state or local environmental provisions when a governmental authority is a party to the proceedings and such proceedings involve potential monetary sanctions that Alliant Energy, IPL and WPL reasonably believe will exceed a specified threshold. Pursuant to the SEC regulations, Alliant Energy, IPL and WPL use a threshold of $1 million for purposes of determining whether disclosure of any such proceedings is required. Applying this threshold, there are no environmental matters to disclose for this period.

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ITEM 1A. RISK FACTORS

The risk factors described in Item 1A in the 20212022 Form 10-K have not changed materially.

ITEM 2. UNREGISTERED SALES OF EQUITY SECURITIES AND USE OF PROCEEDS

A summary of Alliant Energy common stock repurchases for the quarter ended March 31, 20222023 was as follows:

Total NumberAverage PriceTotal Number of SharesMaximum Number (or ApproximateTotal NumberAverage PriceTotal Number of SharesMaximum Number (or Approximate
of SharesPaid PerPurchased as Part ofDollar Value) of Shares That Mayof SharesPaid PerPurchased as Part ofDollar Value) of Shares That May
PeriodPeriodPurchased (a)SharePublicly Announced PlanYet Be Purchased Under the Plan (a)PeriodPurchased (a)SharePublicly Announced PlanYet Be Purchased Under the Plan (a)
January 1 through January 31January 1 through January 314,227$60.98N/AJanuary 1 through January 314,786$55.44N/A
February 1 through February 28February 1 through February 282,91856.38N/AFebruary 1 through February 283,38253.44N/A
March 1 through March 31March 1 through March 3159460.58N/AMarch 1 through March 3164352.11N/A
7,73959.228,81154.43

(a)All shares were purchased on the open market and held in a rabbi trust under the Alliant Energy Deferred Compensation Plan. There is no limit on the number of shares of Alliant Energy common stock that may be held under the Deferred Compensation Plan, which currently does not have an expiration date.

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ITEM 6. EXHIBITS

The following Exhibits are filed herewith or incorporated herein by reference.
Exhibit NumberDescription
4.1
4.2
10.14.3
31.1
31.2
31.3
31.4
31.5
31.6
32.1
32.2
32.3
101.INSInline XBRL Instance Document - the instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document
101.SCHInline XBRL Taxonomy Extension Schema Document
101.CALInline XBRL Taxonomy Extension Calculation Linkbase Document
101.LABInline XBRL Taxonomy Extension Label Linkbase Document
101.PREInline XBRL Taxonomy Extension Presentation Linkbase Document
101.DEFInline XBRL Taxonomy Extension Definition Linkbase Document
104Cover Page Interactive Data File (embedded within the Inline XBRL document)

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, Alliant Energy Corporation, Interstate Power and Light Company and Wisconsin Power and Light Company have each duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized on the 29th5th day of April 2022.May 2023.

ALLIANT ENERGY CORPORATION
Registrant
By: /s/ Benjamin M. BilitzChief Accounting Officer and Controller
Benjamin M. Bilitz(Principal Accounting Officer and Authorized Signatory)
INTERSTATE POWER AND LIGHT COMPANY
Registrant
By: /s/ Benjamin M. BilitzChief Accounting Officer and Controller
Benjamin M. Bilitz(Principal Accounting Officer and Authorized Signatory)
WISCONSIN POWER AND LIGHT COMPANY
Registrant
By: /s/ Benjamin M. BilitzChief Accounting Officer and Controller
Benjamin M. Bilitz(Principal Accounting Officer and Authorized Signatory)

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