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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, 2022

or

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

lnt-20220331_g1.jpg

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:
Alliant Energy Corporation, Common Stock, $0.01 par value, 250,813,728 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)



TABLE OF CONTENTS
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DEFINITIONS
The following abbreviations or acronyms used in this report are defined below:
Abbreviation or Acronym Definition Abbreviation or Acronym Definition
2021 Form 10-K
Combined Annual Report on Form 10-K filed by Alliant Energy, IPL and WPL for the year ended Dec. 31, 2021
IPL Interstate Power and Light Company
AEF Alliant Energy Finance, LLC IUB Iowa Utilities Board
AFUDC Allowance for funds used during construction MDA Management’s Discussion and Analysis of Financial Condition and Results of Operations
Alliant Energy Alliant Energy Corporation MISO Midcontinent Independent System Operator, Inc.
ATC American Transmission Company LLC MW Megawatt
ATC Holdings Interest in American Transmission Company LLC and ATC Holdco LLC MWh Megawatt-hour
Corporate Services Alliant Energy Corporate Services, Inc. N/A Not applicable
DAEC Duane Arnold Energy Center Note(s) Combined Notes to Condensed Consolidated Financial Statements
Dth Dekatherm OPEB Other postretirement benefits
EGU Electric generating unit PPA Purchased power agreement
EPA U.S. Environmental Protection Agency PSCW Public Service Commission of Wisconsin
EPS Earnings per weighted average common share SEC Securities and Exchange Commission
FERC Federal Energy Regulatory Commission U.S. United States of America
Financial Statements Condensed Consolidated Financial Statements West Riverside West Riverside Energy Center
FTR Financial transmission right Whiting Petroleum Whiting Petroleum Corporation
GAAP U.S. generally accepted accounting principles WPL Wisconsin 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 terrorist incidents, including physical attacks and cyber attacks, 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;
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, deferred expenditures, deferred tax assets, tax 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;
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 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;
employee workforce factors, including changes in key executives, ability to hire and retain employees with specialized skills, ability to create desired corporate culture, collective bargaining agreements and negotiations, work stoppages or restructurings;
any material post-closing payments 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;
1

weather effects on results of utility operations;
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;
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 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 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 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;
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 valuations and 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 2021 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.
2

PART I. FINANCIAL INFORMATION
ITEM 1. CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (UNAUDITED)
ALLIANT ENERGY CORPORATION
CONDENSED CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)
For the Three Months
Ended March 31,
2022 2021
(in millions, except per share amounts)
Revenues:
Electric utility $773 $701
Gas utility 262 170
Other utility 11 13
Non-utility 22 17
Total revenues 1,068 901
Operating expenses:
Electric production fuel and purchased power 168 133
Electric transmission service 138 134
Cost of gas sold 168 100
Other operation and maintenance 153 146
Depreciation and amortization 166 164
Taxes other than income taxes 27 26
Total operating expenses 820 703
Operating income 248 198
Other (income) and deductions:
Interest expense 74 69
Equity income from unconsolidated investments, net (15) (15)
Allowance for funds used during construction (11) (4)
Other 2
Total other (income) and deductions 48 52
Income before income taxes 200 146
Income tax expense (benefit) 8 (28)
Net income 192 174
Preferred dividend requirements of Interstate Power and Light Company 3
Net income attributable to Alliant Energy common shareowners $192 $171
Weighted average number of common shares outstanding:
Basic 250.6 250.0
Diluted 250.9 250.4
Earnings per weighted average common share attributable to Alliant Energy common shareowners (basic and diluted)
$0.77 $0.68

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
3

ALLIANT ENERGY CORPORATION
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 $67 $39
Accounts receivable, less allowance for expected credit losses 481 440
Production fuel, at weighted average cost 39 51
Gas stored underground, at weighted average cost 27 82
Materials and supplies, at weighted average cost 119 113
Regulatory assets 88 104
Other 271 240
Total current assets 1,092 1,069
Property, plant and equipment, net 15,192 14,987
Investments:
ATC Holdings 346 338
Other 187 179
Total investments 533 517
Other assets:
Regulatory assets 1,831 1,836
Deferred charges and other 191 144
Total other assets 2,022 1,980
Total assets $18,839 $18,553
LIABILITIES AND EQUITY
Current liabilities:
Current maturities of long-term debt $333 $633
Commercial paper 276 515
Accounts payable 383 436
Accrued taxes 66 58
Regulatory liabilities 251 186
Other 212 226
Total current liabilities 1,521 2,054
Long-term debt, net (excluding current portion) 7,383 6,735
Other liabilities:
Deferred tax liabilities 1,958 1,927
Regulatory liabilities 1,121 1,085
Pension and other benefit obligations 363 374
Other 416 388
Total other liabilities 3,858 3,774
Commitments and contingencies (Note 12)
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 outstanding
3 3
Additional paid-in capital 2,750 2,749
Retained earnings 3,336 3,250
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)
Total Alliant Energy Corporation common equity 6,077 5,990
Total liabilities and equity $18,839 $18,553

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
4

ALLIANT ENERGY CORPORATION
CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)
For the Three Months
Ended March 31,
2022 2021
(in millions)
Cash flows from operating activities:
Net income $192 $174
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization
166 164
Deferred tax expense (benefit) and tax credits 18 (29)
Other (6) 4
Other changes in assets and liabilities:
Accounts receivable (161) (126)
Gas stored underground 55 20
Derivative assets (85) 6
Regulatory assets 19 (4)
Accounts payable (37) (6)
Regulatory liabilities 92 (60)
Deferred income taxes 15 58
Other (17) (56)
Net cash flows from operating activities 251 145
Cash flows used for investing activities:
Construction and acquisition expenditures:
Utility business (307) (214)
Other (23) (17)
Cash receipts on sold receivables 115 209
Other (8) (16)
Net cash flows used for investing activities (223) (38)
Cash flows from (used for) financing activities:
Common stock dividends (107) (102)
Proceeds from issuance of long-term debt 650
Payments to retire long-term debt (300)
Net change in commercial paper (239) (53)
Other (1) 10
Net cash flows from (used for) financing activities 3 (145)
Net increase (decrease) in cash, cash equivalents and restricted cash 31 (38)
Cash, cash equivalents and restricted cash at beginning of period 40 56
Cash, cash equivalents and restricted cash at end of period $71 $18
Supplemental cash flows information:
Cash paid during the period for:
Interest ($62) ($59)
Significant non-cash investing and financing activities:
Accrued capital expenditures $134 $64
Beneficial interest obtained in exchange for securitized accounts receivable $227 $107

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
5

INTERSTATE POWER AND LIGHT COMPANY
CONDENSED CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)
For the Three Months
Ended March 31,
2022 2021
(in millions)
Revenues:
Electric utility $400 $386
Gas utility 139 91
Steam and other 11 12
Total revenues 550 489
Operating expenses:
Electric production fuel and purchased power 67 59
Electric transmission service 97 92
Cost of gas sold 85 50
Other operation and maintenance 83 77
Depreciation and amortization 94 94
Taxes other than income taxes 14 14
Total operating expenses 440 386
Operating income 110 103
Other (income) and deductions:
Interest expense 37 35
Allowance for funds used during construction (3) (2)
Total other (income) and deductions 34 33
Income before income taxes 76 70
Income tax benefit (11) (12)
Net income 87 82
Preferred dividend requirements 3
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.
6

INTERSTATE 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 $62 $34
Accounts receivable, less allowance for expected credit losses 257 241
Income tax refunds receivable 25 8
Production fuel, at weighted average cost 28 29
Gas stored underground, at weighted average cost 11 40
Materials and supplies, at weighted average cost 71 70
Regulatory assets 60 73
Other 85 69
Total current assets 599 564
Property, plant and equipment, net 7,976 7,983
Other assets:
Regulatory assets 1,372 1,370
Deferred charges and other 103 79
Total other assets 1,475 1,449
Total assets $10,050 $9,996
LIABILITIES AND EQUITY
Current liabilities:
Accounts payable $135 $173
Accounts payable to associated companies 46 39
Regulatory liabilities 122 84
Accrued taxes 57 56
Accrued interest 35 36
Other 62 67
Total current liabilities 457 455
Long-term debt, net 3,644 3,643
Other liabilities:
Deferred tax liabilities 1,107 1,083
Regulatory liabilities 632 607
Pension and other benefit obligations 124 127
Other 311 312
Total other liabilities 2,174 2,129
Commitments and contingencies (Note 12)
Equity:
Interstate Power and Light Company common equity:
Common stock - $2.50 par value - 24,000,000 shares authorized; 13,370,788 shares outstanding
33 33
Additional paid-in capital 2,807 2,807
Retained earnings 935 929
Total Interstate Power and Light Company common equity 3,775 3,769
Total liabilities and equity $10,050 $9,996

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
7

INTERSTATE POWER AND LIGHT COMPANY
CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)
For the Three Months
Ended March 31,
2022 2021
(in millions)
Cash flows from (used for) operating activities:
Net income $87 $82
Adjustments to reconcile net income to net cash flows from (used for) operating activities:
Depreciation and amortization 94 94
Deferred tax expense (benefit) and tax credits 15 (2)
Other (2) (1)
Other changes in assets and liabilities:
Accounts receivable (128) (133)
Income tax refunds receivable (17) (3)
Gas stored underground 29 12
Derivative assets (43) 10
Regulatory assets 9 (16)
Regulatory liabilities 59 (19)
Other (14) (69)
Net cash flows from (used for) operating activities 89 (45)
Cash flows from investing activities:
Construction and acquisition expenditures (96) (106)
Cash receipts on sold receivables 115 209
Other (1) (5)
Net cash flows from investing activities 18 98
Cash flows used for financing activities:
Common stock dividends (81) (101)
Other 2 9
Net cash flows used for financing activities (79) (92)
Net increase (decrease) in cash, cash equivalents and restricted cash 28 (39)
Cash, cash equivalents and restricted cash at beginning of period 34 50
Cash, cash equivalents and restricted cash at end of period $62 $11
Supplemental cash flows information:
Cash (paid) refunded during the period for:
Interest ($37) ($37)
Income taxes, net $— $7
Significant non-cash investing and financing activities:
Accrued capital expenditures $27 $31
Beneficial interest obtained in exchange for securitized accounts receivable $227 $107

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
8

WISCONSIN POWER AND LIGHT COMPANY
CONDENSED CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)
For the Three Months
Ended March 31,
2022 2021
(in millions)
Revenues:
Electric utility $373 $315
Gas utility 123 79
Other 1
Total revenues 496 395
Operating expenses:
Electric production fuel and purchased power 101 74
Electric transmission service 41 42
Cost of gas sold 83 50
Other operation and maintenance 58 59
Depreciation and amortization 70 69
Taxes other than income taxes 12 11
Total operating expenses 365 305
Operating income 131 90
Other (income) and deductions:
Interest expense 27 26
Allowance for funds used during construction (9) (2)
Other 1
Total other (income) and deductions 18 25
Income before income taxes 113 65
Income tax expense (benefit) 21 (19)
Net income $92 $84
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.
9

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 losses 211 188
Production fuel, at weighted average cost 11 23
Gas stored underground, at weighted average cost 16 42
Materials and supplies, at weighted average cost 45 41
Regulatory assets 28 31
Prepaid gross receipts tax 30 40
Other 102 86
Total current assets 447 453
Property, plant and equipment, net 6,747 6,538
Other assets:
Regulatory assets 459 466
Deferred charges and other 90 61
Total other assets 549 527
Total assets $7,743 $7,518
LIABILITIES AND EQUITY
Current liabilities:
Current maturities of long-term debt $250 $250
Commercial paper 157 236
Accounts payable 185 190
Accounts payable to associated companies 34 39
Regulatory liabilities 129 102
Other 102 73
Total current liabilities 857 890
Long-term debt, net (excluding current portion) 2,180 2,179
Other liabilities:
Deferred tax liabilities
759 753
Regulatory liabilities 489 478
Pension and other benefit obligations 154 159
Other 253 236
Total other liabilities 1,655 1,626
Commitments and contingencies (Note 12)
Equity:
Wisconsin Power and Light Company common equity:
Common stock - $5 par value - 18,000,000 shares authorized; 13,236,601 shares outstanding
66 66
Additional paid-in capital 1,884 1,704
Retained earnings 1,101 1,053
Total Wisconsin Power and Light Company common equity 3,051 2,823
Total liabilities and equity $7,743 $7,518

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
10

WISCONSIN POWER AND LIGHT COMPANY
CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)
For the Three Months
Ended March 31,
2022 2021
(in millions)
Cash flows from operating activities:
Net income $92 $84
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization 70 69
Deferred tax benefit and tax credits (2) (28)
Other (3) 4
Other changes in assets and liabilities:
Accounts receivable (23) 9
Gas stored underground 26 9
Derivative assets (42) (4)
Accounts payable (24) (24)
Regulatory liabilities 32 (41)
Accrued taxes 21 8
Deferred income taxes 8 44
Other 12 18
Net cash flows from operating activities 167 148
Cash flows used for investing activities:
Construction and acquisition expenditures (212) (108)
Other (5) (11)
Net cash flows used for investing activities (217) (119)
Cash flows from (used for) financing activities:
Common stock dividends (44) (42)
Capital contributions from parent 180 125
Net change in commercial paper (79) (109)
Other (5) (4)
Net cash flows from (used for) financing activities 52 (30)
Net increase (decrease) in cash, cash equivalents and restricted cash 2 (1)
Cash, cash equivalents and restricted cash at beginning of period 2 3
Cash, cash equivalents and restricted cash at end of period $4 $2
Supplemental cash flows information:
Cash paid during the period for:
Interest ($23) ($21)
Significant non-cash investing and financing activities:
Accrued capital expenditures $104 $32

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
11

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 2021 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, 2022 are not necessarily indicative of results that may be expected for the year ending December 31, 2022.

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, Cash Equivalents and Restricted Cash - At March 31, 2022, Alliant Energy’s and IPL’s cash and cash equivalents included $59 million of money market fund investments, with an interest rate of 0.3%.

NOTE 2. REGULATORY MATTERS
Regulatory Assets and Regulatory Liabilities -
Regulatory assets were comprised of the following items (in millions):
Alliant Energy IPL WPL
March 31,
2022
December 31,
2021
March 31,
2022
December 31,
2021
March 31,
2022
December 31,
2021
Tax-related $949 $934 $896 $884 $53 $50
Pension and OPEB costs 453 462 224 228 229 234
Asset retirement obligations 134 128 94 89 40 39
Assets retired early 88 92 64 66 24 26
IPL’s DAEC PPA amendment 84 90 84 90
WPL’s Western Wisconsin gas distribution expansion investments 50 52 50 52
Commodity cost recovery 42 42 2 2 40 40
Other 119 140 68 84 51 56
$1,919 $1,940 $1,432 $1,443 $487 $497

Regulatory liabilities were comprised of the following items (in millions):
Alliant Energy IPL WPL
March 31,
2022
December 31,
2021
March 31,
2022
December 31,
2021
March 31,
2022
December 31,
2021
Tax-related $578 $585 $310 $312 $268 $273
Cost of removal obligations 391 384 256 252 135 132
Derivatives 258 166 125 77 133 89
Electric transmission cost recovery 50 51 29 27 21 24
WPL’s West Riverside liquidated damages 35 36 35 36
Other 60 49 34 23 26 26
$1,372 $1,271 $754 $691 $618 $580

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NOTE 3. RECEIVABLES
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. The transfers of receivables meet the criteria for sale accounting established by the transfer of financial assets accounting rules. As of March 31, 2022, IPL had $109 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):
2022 2021
Maximum outstanding aggregate cash proceeds $36 $100
Average outstanding aggregate cash proceeds 4 30

The attributes of IPL’s receivables sold under the Receivables Agreement were as follows (in millions):
March 31, 2022 December 31, 2021
Customer accounts receivable $142 $125
Unbilled utility revenues 96 104
Receivables sold to third party 238 229
Less: cash proceeds 1 1
Deferred proceeds 237 228
Less: allowance for expected credit losses 10 14
Fair value of deferred proceeds $227 $214

As of March 31, 2022, outstanding receivables past due under the Receivables Agreement were $24 million. Additional attributes of IPL’s receivables sold under the Receivables Agreement for the three months ended March 31 were as follows (in millions):
2022 2021
Collections $561 $529
Write-offs, net of recoveries 2 2

NOTE 4. 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):
2022 2021
ATC Holdings ($11) ($11)
Other (4) (4)
($15) ($15)

NOTE 5. COMMON EQUITY
Common Share Activity - A summary of Alliant Energy’s common stock activity was as follows:
Shares outstanding, January 1, 2022
250,474,529 
Shareowner Direct Plan 116,431 
Equity-based compensation plans 222,768 
Shares outstanding, March 31, 2022
250,813,728 

13

Changes in Shareowners’ Equity - A summary of changes in shareowners’ equity was as follows (in millions):
Alliant Energy Total Alliant Energy Common Equity
Accumulated Shares in Cumulative
Additional Other Deferred Preferred
Common Paid-In Retained Comprehensive Compensation Stock Total
Stock Capital Earnings Loss Trust of IPL Equity
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 shareowners 192 192
Common stock dividends ($0.4275 per share)
(107) (107)
Shareowner Direct Plan issuances 7 7
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 shareowners 171 171
Common stock dividends ($0.4025 per share)
(102) (102)
Shareowner Direct Plan issuances 1 7 8
Equity-based compensation plans and other 1 1
Ending balance, March 31, 2021
$3 $2,712 $3,063 ($1) ($11) $200 $5,966
IPL Total IPL Common Equity
Additional Cumulative
Common Paid-In Retained Preferred Total
Stock Capital Earnings Stock Equity
Three Months Ended March 31, 2022
Beginning balance, December 31, 2021
$33 $2,807 $929 $— $3,769
Net income available for common stock 87 87
Common stock dividends (81) (81)
Ending 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 stock 79 79
Common stock dividends (101) (101)
Ending balance, March 31, 2021
$33 $2,752 $957 $200 $3,942
WPL Additional Total
Common Paid-In Retained Common
Stock Capital Earnings Equity
Three Months Ended March 31, 2022
Beginning balance, December 31, 2021
$66 $1,704 $1,053 $2,823
Net income 92 92
Common stock dividends (44) (44)
Capital contributions from parent 180 180
Ending 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 income 84 84
Common stock dividends (42) (42)
Capital contributions from parent 125 125
Ending balance, March 31, 2021
$66 $1,584 $995 $2,645
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NOTE 6. DEBT
NOTE 6(a) Short-term Debt - 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, 2022 Alliant Energy IPL WPL
Amount outstanding $276 $— $157
Weighted average interest rates 0.6% N/A 0.5%
Available credit facility capacity $724 $250 $143
Alliant Energy IPL WPL
Three Months Ended March 31 2022 2021 2022 2021 2022 2021
Maximum amount outstanding (based on daily outstanding balances) $577 $578 $— $— $252 $275
Average amount outstanding (based on daily outstanding balances) $443 $424 $— $— $205 $189
Weighted average interest rates 0.3% 0.2% —% —% 0.3% 0.2%

NOTE 6(b) Long-term Debt - In February 2022, AEF issued $350 million of 3.6% senior notes due 2032. The net proceeds from the issuance were used to reduce Alliant Energy’s outstanding commercial paper and for general corporate purposes. In March 2022, AEF entered into a $300 million variable rate (1% as of March 31, 2022) term loan credit agreement (with Alliant Energy as guarantor), which expires in March 2024, and used the borrowings under this agreement to retire its $300 million variable rate term loan credit agreement that expired in March 2022.

NOTE 7. REVENUES
Disaggregation of revenues from contracts with customers, which correlates to revenues for each reportable segment, was as follows (in millions):
Alliant Energy IPL WPL
Three Months Ended March 31 2022 2021 2022 2021 2022 2021
Electric Utility:
Retail - residential $293 $262 $150 $139 $143 $123
Retail - commercial 188 172 118 110 70 62
Retail - industrial 211 202 111 112 100 90
Wholesale 47 40 15 11 32 29
Bulk power and other 34 25 6 14 28 11
Total Electric Utility 773 701 400 386 373 315
Gas Utility:
Retail - residential 158 99 85 52 73 47
Retail - commercial 82 53 40 27 42 26
Retail - industrial 8 5 5 3 3 2
Transportation/other 14 13 9 9 5 4
Total Gas Utility 262 170 139 91 123 79
Other Utility:
Steam 9 9 9 9
Other utility 2 4 2 3 1
Total Other Utility 11 13 11 12 1
Non-Utility and Other:
Travero and other 22 17
Total Non-Utility and Other 22 17
Total revenues $1,068 $901 $550 $489 $496 $395
NOTE 8. 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 Energy IPL WPL
2022 2021 2022 2021 2022 2021
Overall income tax rate 4% (19%) (14%) (17%) 19% (29%)

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Deferred Tax Assets and Liabilities -
Carryforwards - At March 31, 2022, carryforwards and expiration dates were estimated as follows (in millions):
Range of Expiration Dates Alliant Energy IPL WPL
Federal net operating losses 2037 $94 $87 $1
State net operating losses 2022-2042 578 13 2
Federal tax credits 2022-2042 589 369 197

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.

NOTE 9. BENEFIT PLANS
NOTE 9(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 Plans OPEB Plans
Alliant Energy 2022 2021 2022 2021
Service cost $2 $3 $1 $1
Interest cost 9 8 1 1
Expected return on plan assets (17) (17) (1) (1)
Amortization of actuarial loss 8 10 1 1
$2 $4 $2 $2
Defined Benefit Pension Plans OPEB Plans
IPL 2022 2021 2022 2021
Service cost $2 $2 $— $—
Interest cost 4 4 1 1
Expected return on plan assets (8) (8) (1) (1)
Amortization of actuarial loss 3 4
$1 $2 $— $—
Defined Benefit Pension Plans OPEB Plans
WPL 2022 2021 2022 2021
Service cost $1 $1 $— $—
Interest cost 4 4 1
Expected return on plan assets (8) (8)
Amortization of actuarial loss 4 5 1
$1 $2 $1 $1

NOTE 9(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 Energy IPL WPL
2022 2021 2022 2021 2022 2021
Compensation expense $4 $3 $2 $1 $2 $1
Income tax benefits 1 1 1

As of March 31, 2022, Alliant Energy’s, IPL’s and WPL’s total unrecognized compensation cost related to share-based compensation awards was $15 million, $8 million and $6 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, performance shares, performance restricted stock units and restricted stock units were granted to key employees as follows. These shares and units will be paid out in shares of common stock, and are therefore accounted for as equity awards.
Weighted Average
Grants Grant Date Fair Value
Performance shares 70,240 $54.45
Performance restricted stock units 80,252 56.62
Restricted stock units 74,360 56.62

As of March 31, 2022, 322,288 shares were included in the calculation of diluted EPS related to the nonvested equity awards.

NOTE 10. DERIVATIVE INSTRUMENTS
Commodity Derivatives -
Notional Amounts - As of March 31, 2022, 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):
FTRs Natural Gas Coal Diesel Fuel
MWhs Years Dths Years Tons Years Gallons Years
Alliant Energy
3,304  2022 175,658  2022-2030 2,653  2022-2023 2,268  2022
IPL 784  2022 94,175  2022-2030 1,053  2022-2023 — 
WPL 2,520  2022 81,483  2022-2030 1,600  2022-2023 2,268  2022

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 Energy IPL WPL
March 31,
2022
December 31,
2021
March 31,
2022
December 31,
2021
March 31,
2022
December 31,
2021
Current derivative assets $151 $113 $68 $48 $83 $65
Non-current derivative assets 110 63 59 36 51 27
Current derivative liabilities 6 8 3 4 3 4
Non-current derivative liabilities 1 1 1 1

During the three months ended March 31, 2022, Alliant Energy’s, IPL’s and WPL’s derivative assets increased primarily as a result of higher natural gas prices. Based on IPL’s and WPL’s natural gas cost recovery mechanisms, this resulted in corresponding increases in derivative regulatory 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, 2022 and December 31, 2021, 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. 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.

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NOTE 11. 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 Energy March 31, 2022 December 31, 2021
Fair Value Fair Value
Carrying Level Level Level Carrying Level Level Level
Amount 1 2 3 Total Amount 1 2 3 Total
Assets:
Money market fund investments $59  $59  $—  $—  $59  $32  $32  $—  $—  $32 
Derivatives 261    251  10  261  176  —  146  30  176 
Deferred proceeds 227      227  227  214  —  —  214  214 
Liabilities:
Derivatives 7    7    7  — 
Long-term debt (incl. current maturities) 7,716    7,971  1  7,972  7,368  —  8,329  8,330 
IPL March 31, 2022 December 31, 2021
Fair Value Fair Value
Carrying Level Level Level Carrying Level Level Level
Amount 1 2 3 Total Amount 1 2 3 Total
Assets:
Money market fund investments $59  $59  $—  $—  $59  $32  $32  $—  $—  $32 
Derivatives 127    120  7  127  84  —  65  19  84 
Deferred proceeds 227      227  227  214  —  —  214  214 
Liabilities:
Derivatives 4    4    4  — 
Long-term debt 3,644    3,738    3,738  3,643  —  4,124  —  4,124 
WPL March 31, 2022 December 31, 2021
Fair Value Fair Value
Carrying Level Level Level Carrying Level Level Level
Amount 1 2 3 Total Amount 1 2 3 Total
Assets:
Derivatives $134  $—  $131  $3  $134  $92  $—  $81  $11  $92 
Liabilities:
Derivatives 3    3    3  —  — 
Long-term debt (incl. current maturities) 2,430    2,592    2,592  2,429  —  2,862  —  2,862 

Information for fair value measurements using significant unobservable inputs (Level 3 inputs) was as follows (in millions):
Alliant Energy Commodity Contract Derivative
Assets and (Liabilities), net Deferred Proceeds
Three Months Ended March 31 2022 2021 2022 2021
Beginning balance, January 1 $29 $29 $214 $188
Total net losses included in changes in net assets (realized/unrealized) (6) (6)
Settlements (a) (13) (7) 13 (81)
Ending balance, March 31
$10 $16 $227 $107
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) $— $—
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IPL Commodity Contract Derivative
Assets and (Liabilities), net Deferred Proceeds
Three Months Ended March 31 2022 2021 2022 2021
Beginning balance, January 1 $18 $26 $214 $188
Total net losses included in changes in net assets (realized/unrealized) (4) (5)
Settlements (a) (7) (6) 13 (81)
Ending balance, March 31
$7 $15 $227 $107
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) $— $—
WPL Commodity Contract Derivative
Assets and (Liabilities), net
Three Months Ended March 31 2022 2021
Beginning balance, January 1 $11 $3
Total net losses included in changes in net assets (realized/unrealized) (2) (1)
Settlements (6) (1)
Ending balance, March 31
$3 $1
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) $—
(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 as follows (in millions):
Alliant Energy IPL WPL
Excluding FTRs FTRs Excluding FTRs FTRs Excluding FTRs FTRs
March 31, 2022 $3 $7 $3 $4 $— $3
December 31, 2021 9 20 8 10 1 10

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

NOTE 12(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, related minimum future commitments were as follows (in millions):
Alliant Energy IPL WPL
Natural gas $939 $472 $467
Coal 127 72 55
Other (a) 135 66 36
$1,201 $610 $558

(a)Includes individual commitments incurred during the normal course of business that exceeded $1 million at March 31, 2022.

NOTE 12(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 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.
19


As of March 31, 2022, the currently known partnership obligations for the abandonment obligations are estimated at $60 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 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, 2022 and December 31, 2021, 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.

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 million as of March 31, 2022 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, 2022 and December 31, 2021.

NOTE 12(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, 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 Energy IPL
Range of estimated future costs $10 
-
$26 $7 
-
$20
Current and non-current environmental liabilities $12 $9

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: 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 Agreements - At March 31, 2022, employees covered by collective bargaining agreements represented 55%, 70% 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. While the process to renew the agreement is underway and a tentative agreement has been reached, Alliant Energy and WPL are currently unable to predict the outcome.

20

NOTE 13. 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 Energy ATC Holdings, Alliant
Utility Non-Utility, Energy
Electric Gas Other Total Parent and Other Consolidated
(in millions)
Three Months Ended March 31, 2022
Revenues $773 $262 $11 $1,046 $22 $1,068
Operating income 181 57 3 241 7 248
Net income attributable to Alliant Energy common shareowners 179 13 192
Three Months Ended March 31, 2021
Revenues $701 $170 $13 $884 $17 $901
Operating income 147 44 2 193