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 2023 Form 10-K. Unless otherwise noted, all “per share” references in MDA refer to earnings per diluted share.

2024 HIGHLIGHTS

Key highlights since the filing of the 2023 Form 10-K include the following:

Customer Investments:

• In March 2024, IPL completed construction of the Duane Arnold solar facility (50 MW in Linn County, Iowa).

• In March 2024 and April 2024, FERC and the PSCW, respectively, approved the sales of WPL’s partial ownership interests in West Riverside to WEC Energy Group, Inc. (100 MW) and Madison Gas and Electric Company (25 MW). These sales are currently expected to occur in June 2024.

• In April 2024, WPL received orders from the PSCW authorizing WPL to construct improvements at the natural gas-fired Neenah Energy Facility and Sheboygan Falls Energy Facility, which would increase the capacity and efficiency of the EGUs.

• In April 2024, IPL and WPL entered into agreements to transfer a portion of the renewable tax credits generated in 2024 and 2025 from certain wind, solar and battery storage facilities to other corporate taxpayers in exchange for cash.

Rate Matters:

• Refer to Note 3 for discussion of WPL’s March 2024 filing for judicial review of PSCW orders related to the recovery and deferral of the return on incremental solar generation construction costs in 2024 and 2025.

Environmental Matters:

• In April 2024, the EPA issued the final Section 111(d) rule for certain fossil-fueled EGUs and repealed the Affordable Clean Energy rule. The final Section 111(d) rule requires states to implement plans to reduce carbon dioxide emissions through various Best System of Emission Reduction measures at affected sources, including retirement, enforceable limits on operational capacity, co-firing with low-GHG fuels, or carbon capture and storage technology. State plans are subject to EPA approval, and must be submitted within 24 months of the final rule’s effective date, which has not yet been determined. The final rule’s compliance requirements will be phased in beginning in 2030 and covers fossil-fueled EGUs that utilize steam boilers to generate electricity, including IPL’s coal-fired Ottumwa Generating Station, George Neal Generating Station, Prairie Creek Generating Station Unit 3 and Louisa Generating Station, and IPL’s natural gas-fired Burlington Generating Station and Prairie Creek Generating Station Unit 4. The final rule does not apply to EGUs that are retired by January 2032 and is not currently expected to impact WPL’s coal-fired Columbia Energy Center or Edgewater Generating Station given current plans to retire these EGUs prior to this deadline. In addition, the final rule does not impact existing natural gas-fired combustion turbines, including IPL’s Marshalltown Generating Station and Emery Generating Station, and WPL’s Riverside Energy Center and West Riverside Energy Center; however, these EGUs could be subject to future Section 111(d) rules to reduce carbon dioxide emissions from existing combustion turbines. Alliant Energy, IPL and WPL are currently unable to predict with certainty the future outcome or impact of these matters, including resolution of ongoing litigation that has been suspended while the EPA revised its regulations.

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• In April 2024, the EPA issued final revised standards under Section 111(b), which establishes carbon dioxide emissions limits from certain new and reconstructed fossil-fueled EGU combustion turbines that commenced operation after May 23, 2023 with a capacity greater than 25 MW. The final revised standards do not apply to IPL’s Marshalltown Generating Station or WPL’s West Riverside Energy Center, which commenced operation prior to the applicability date of the final revised standards. Alliant Energy, IPL and WPL are currently unable to predict with certainty the future outcome or impact of these revised standards, including resolution of ongoing litigation that has been suspended while the EPA revised its regulations.

• In April 2024, the EPA issued a final rule that revises discharge limits for specific categories of wastewater from existing coal-fired EGUs. The new limitations will be implemented in each facility’s wastewater discharge permits issued by state agencies and become effective as soon as possible but no later than December 31, 2029. Alliant Energy, IPL and WPL are currently evaluating the final rule and are unable to predict with certainty future compliance impacts.

• In April 2024, the EPA issued revisions to the Coal Combustion Residuals Rule, which significantly expand the scope of regulation to include coal ash ponds at sites that no longer produce electricity and inactive landfills, including some IPL and WPL facilities. Alliant Energy, IPL and WPL are currently evaluating the revised Coal Combustion Residuals Rule and are unable to predict with certainty the future outcome or impact of these updates.

Legislative Matters:

• In May 2024, the Major Economic Growth Attraction program was enacted in Iowa, which offers various tax incentives for up to two qualified businesses for certain large-scale projects with capital investments greater than $1 billion constructed on certified sites greater than 250 acres in Iowa. The most significant provision of this program for Alliant Energy encourages economic development in IPL’s service territory. Alliant Energy has various development-ready sites throughout Iowa, including the 1,300-acre Big Cedar Industrial Center Mega-site in Cedar Rapids, Iowa, and the 465-acre Prairie View Industrial Center Super Park in Ames, Iowa.

• In May 2024, legislation was enacted in Iowa related to the advance rate-making principles for certain investments in Iowa. The most signification provisions of this legislation for Alliant Energy would allow IPL to include electric storage and nuclear-fired generation projects in the advance rate-making principles request process prior to making these investments in Iowa, and require IPL to obtain a certificate of public convenience, use and necessity (GCU Certificate) from the IUB in order to construct electric storage projects.

RESULTS OF OPERATIONS

Financial Results Overview - 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. 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):

			2024												2023
			Income (Loss)						EPS						Income (Loss)						EPS
Utilities and Corporate Services			$159						$0.62						$163						$0.65
ATC Holdings			9						0.04						9						0.04
Non-utility and Parent			(10)						(0.04)						(9)						(0.04)
Alliant Energy Consolidated			$158						$0.62						$163						$0.65

Alliant Energy’s Utilities and Corporate Services net income decreased by $4 million for the three-month period, primarily due to lower retail electric and gas sales due to impacts of warmer than normal temperatures during the three months ended March 31, 2024, and higher financing and depreciation expenses. These items were partially offset by higher revenue requirements from WPL’s capital investments.

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Net Income Variances - The following items contributed to increased (decreased) net income for the three months ended March 31, 2024 compared to the same period in 2023 (in millions):

			Alliant Energy						IPL						WPL
Revenues:
Changes in electric utility (Refer to details below)			$23						$4						$19
Changes in gas utility (Refer to details below)			(71)						(42)						(29)
Changes in other utility			2						2						—
Changes in total revenues			(46)						(36)						(10)
Operating expenses:
Changes in electric production fuel and purchased power (Refer to details below)			(6)						(20)						13
Changes in electric transmission service			(6)						1						(7)
Changes in cost of gas sold (Refer to details below)			67						35						33
Changes in other operation and maintenance (Refer to details below)			14						9						3
Changes in depreciation and amortization (Higher primarily due to WPL’s solar generation placed in service in 2023, as well as WPL’s amortization of liquidated damages related to West Riverside procurement contracts, which resulted in reductions to depreciation and amortization expenses in the first quarter of 2023)			(23)						—						(22)
Changes in total operating expenses			46						25						20
Changes in operating income			—						(11)						10
Other income and deductions:
Changes in interest expense (Higher primarily due to financings completed in 2024 and 2023)			(13)						(5)						(5)
Changes in equity income from unconsolidated investments, net (Refer to Note 5 for details)			(2)						—						—
Changes in AFUDC (Primarily due to changes in levels of CWIP balances related to solar generation and battery storage)			—						7						(7)
Changes in Other			2						1						—
Changes in total other income and deductions			(13)						3						(12)
Changes in income before income taxes			(13)						(8)						(2)
Changes in income taxes (Refer to Note 9 for details)			8						(1)						6
Changes in net income			($5)						($9)						$4

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 Energy			Electric																								Gas
			Revenues												MWhs Sold												Revenues												Dths Sold
			2024						2023						2024						2023						2024						2023						2024						2023
Retail			$706						$686						5,989						6,201						$192						$262						20,117						22,310
Sales for resale:
Wholesale			47						46						679						698						N/A						N/A						N/A						N/A
Bulk power and other			21						23						1,670						1,243						N/A						N/A						N/A						N/A
Transportation/Other			17						13						15						15						13						14						33,908						32,614
			$791						$768						8,353						8,157						$205						$276						54,025						54,924

IPL			Electric																								Gas
			Revenues												MWhs Sold												Revenues												Dths Sold
			2024						2023						2024						2023						2024						2023						2024						2023
Retail			$376						$362						3,365						3,544						$101						$141						10,205						11,459
Sales for resale:
Wholesale			13						12						182						187						N/A						N/A						N/A						N/A
Bulk power and other			(3)						7						324						496						N/A						N/A						N/A						N/A
Transportation/Other			6						7						8						8						7						9						11,695						12,035
			$392						$388						3,879						4,235						$108						$150						21,900						23,494

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WPL			Electric																								Gas
			Revenues												MWhs Sold												Revenues												Dths Sold
			2024						2023						2024						2023						2024						2023						2024						2023
Retail			$330						$324						2,624						2,657						$91						$121						9,912						10,851
Sales for resale:
Wholesale			34						34						497						511						N/A						N/A						N/A						N/A
Bulk power and other			24						16						1,346						747						N/A						N/A						N/A						N/A
Transportation/Other			11						6						7						7						6						5						22,213						20,579
			$399						$380						4,474						3,922						$97						$126						32,125						31,430

Sales Trends and Temperatures - Alliant Energy’s retail electric sales volumes decreased 3% for the three months ended March 31, 2024 compared to the same period in 2023, primarily due to changes in sales volumes to industrial customers due to standby service customers that can use other generation and changes in temperatures, partially offset by an additional day of sales due to leap year in 2024. Alliant Energy’s retail gas sales volumes decreased 10% for the three months ended March 31, 2024 compared to the same period in 2023, primarily due to changes in temperatures, partially offset by an additional day of sales due to leap year in 2024.

Estimated decreases to operating income from the impacts of temperatures for the three months ended March 31 were as follows (in millions):

			Electric																		Gas
			2024						2023						Change																								2024						2023						Change
IPL			($9)						($4)						($5)																								($6)						($3)						($3)
WPL			(10)						(5)						(5)																								(5)						(3)						(2)
Total Alliant Energy			($19)						($9)						($10)																								($11)						($6)						($5)

Electric Sales for Resale - Bulk Power and Other - Bulk power and other volume changes were 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 bulk power and other revenues were largely offset by changes in fuel-related costs, and therefore did not have a significant impact on operating income.

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.

Electric Utility Revenue Variances - The following items contributed to increased (decreased) electric utility revenues for the three months ended March 31, 2024 compared to the same period in 2023 (in millions):

			Alliant Energy						IPL						WPL
Higher revenue requirements at WPL (a)			$38						$—						$38
Estimated changes in sales volumes caused by temperatures			(10)						(5)						(5)
Higher (lower) sales for resale bulk power and other revenues			(2)						(10)						8
Higher (lower) revenues due to changes in retail electric fuel-related costs (Refer to Electric Production Fuel and Purchased Power Expenses Variances below) (a)			(1)						26						(27)
Other			(2)						(7)						5
			$23						$4						$19

(a)In December 2023, the PSCW issued an order authorizing an annual base rate increase of $49 million for WPL’s retail electric customers, covering the 2024 forward-looking Test Period, which reflects revenue requirement impacts of increasing electric rate base and lower forecasted fuel-related expenses.

Gas Utility Revenue Variances - The following items contributed to increased (decreased) gas utility revenues for the three months ended March 31, 2024 compared to the same period in 2023 (in millions):

			Alliant Energy						IPL						WPL
Lower revenues due to changes in gas costs (Refer to Cost of Gas Sold Expense Variances below)			($67)						($35)						($33)
Estimated changes in sales volumes caused by temperatures			(5)						(3)						(2)
Higher revenue requirements at WPL (a)			5						—						5
Other			(4)						(4)						1
			($71)						($42)						($29)

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(a)In December 2023, the PSCW issued an order authorizing an annual base rate increase of $13 million for WPL’s retail gas customers, covering the 2024 forward-looking Test Period, which reflects revenue requirement impacts of increasing gas rate base.

Electric Production Fuel and Purchased Power Expenses Variances - The following items contributed to (increased) decreased electric production fuel and purchased power expenses for the three months ended March 31, 2024 compared to the same period in 2023 (in millions):

			Alliant Energy						IPL						WPL
Lower electric production fuel costs (a)			$53						$38						$15
Changes in regulatory recovery of retail electric fuel-related costs			(31)						(38)						7
Higher purchased power expense (b)			(27)						(20)						(7)
Other			(1)						—						(2)
			($6)						($20)						$13

(a)Electric production fuel costs decreased primarily due to lower natural gas prices in the first quarter of 2024 compared to the same period in 2023 and lower natural gas volumes due to lower dispatch of IPL’s natural gas-fired EGUs in 2024, partially offset by higher coal volumes due to higher dispatch of WPL’s coal-fired EGUs in 2024.

(b)Purchased power expense increased primarily due to higher prices for electricity purchased by IPL and WPL.

Cost of Gas Sold Expense Variances - The following items contributed to (increased) decreased cost of gas sold expense for the three months ended March 31, 2024 compared to the same period in 2023 (in millions):

			Alliant Energy						IPL						WPL
Lower natural gas prices and lower retail gas volumes primarily due to changes in temperatures			$75						$50						$25
Changes in the regulatory recovery of gas costs			(6)						(14)						8
Other			(2)						(1)						—
			$67						$35						$33

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, 2024 compared to the same period in 2023 (in millions):

			Alliant Energy						IPL						WPL
Lower generation and energy delivery expenses			$8						$1						$7
Lower energy efficiency expense at IPL (mostly offset by higher revenues)			7						7						—
Other			(1)						1						(4)
			$14						$9						$3

LIQUIDITY AND CAPITAL RESOURCES

The liquidity and capital resources summary included in the 2023 Form 10-K has not changed materially, except as described below.

Liquidity Position - At March 31, 2024, Alliant Energy had $32 million of cash and cash equivalents, $666 million ($166 million at the parent company, $200 million at IPL and $300 million at WPL) of available capacity under the single revolving credit facility and $92 million of available capacity at IPL under its sales of accounts receivable program.

Capital Structure - Capital structures at March 31, 2024 were as follows (Long-term Debt (including current maturities) (LD); Short-term Debt (SD); Common Equity (CE)):

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Cash Flows - Selected information from the cash flows statements was as follows (in millions):

			Alliant Energy												IPL												WPL
			2024						2023						2024						2023						2024						2023
Cash, cash equivalents and restricted cash, January 1			$63						$24						$53						$15						$7						$5
Cash flows from (used for):
Operating activities			307						188						76						24						241						185
Investing activities			(353)						(263)						(107)						70						(213)						(295)
Financing activities			18						212						(10)						(74)						(24)						191
Net increase (decrease)			(28)						137						(41)						20						4						81
Cash, cash equivalents and restricted cash, March 31			$35						$161						$12						$35						$11						$86

Operating Activities - The following items contributed to increased (decreased) operating activity cash flows for the three months ended March 31, 2024 compared to the same period in 2023 (in millions):

			Alliant Energy						IPL						WPL
Higher collections from WPL’s retail electric and gas base rate increases			$43						$—						$43
Changes in the sales of accounts receivable at IPL			18						18						—
Decreased collections from IPL’s and WPL’s retail customers caused by temperature impacts on electric and gas sales			(15)						(8)						(7)
Other (primarily due to other changes in working capital)			73						42						20
			$119						$52						$56

Investing Activities - The following items contributed to increased (decreased) investing activity cash flows for the three months ended March 31, 2024 compared to the same period in 2023 (in millions):

			Alliant Energy						IPL						WPL
(Higher) lower utility construction and acquisition expenditures (a)			($61)						($152)						$91
Proceeds from sale of partial ownership interest in West Riverside in 2023			(25)						—						(25)
Changes in the amount of cash receipts on sold receivables			(18)						(18)						—
Other			14						(7)						16
			($90)						($177)						$82

(a)Largely due to higher expenditures for IPL’s solar generation and WPL’s battery storage, partially offset by lower expenditures for WPL’s solar generation.

Financing Activities - The following items contributed to increased (decreased) financing activity cash flows for the three months ended March 31, 2024 compared to the same period in 2023 (in millions):

			Alliant Energy						IPL						WPL
Higher payments to retire long-term debt			($300)						$—						$—
Lower net proceeds from issuance of long-term debt			(265)						—						—
(Higher) lower common stock dividends			(10)						20						(3)
Higher (lower) capital contributions from IPL’s and WPL’s parent company, Alliant Energy			—						50						(125)
Net changes in the amount of commercial paper and other short-term borrowings outstanding			391						—						(88)
Other			(10)						(6)						1
			($194)						$64						($215)

Common Stock Issuances - Refer to Note 6 for discussion of common stock issuances by Alliant Energy in 2024.

Long-term Debt - Refer to Note 7(b) for discussion of various issuances and/or retirements of long-term debt by AEF and WPL in 2024.

Impact of Credit Ratings on Liquidity and Collateral Obligations -

Ratings Triggers - In March 2024, Standard & Poor’s Ratings Services changed Alliant Energy’s and IPL’s outlooks from stable to negative. These outlook changes are not expected to have a material impact on Alliant Energy’s and IPL’s liquidity or collateral obligations.

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 2023 Form 10-K and has not changed materially from the items reported in the 2023 Form 10-K, except for the items described in Notes 4, 7 and 13.

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OTHER MATTERS

Critical Accounting Estimates - The summary of critical accounting estimates included in the 2023 Form 10-K has not changed materially, except as described below.

Long-Lived Assets -

Regulated Operations -

Solar Generation Projects Recently Completed or Under Construction - Alliant Energy and WPL currently expect construction costs associated with WPL’s approximately 1,100 MW of new solar generation will exceed the construction cost estimates previously approved by the PSCW by approximately $180 million. In February 2024, the PSCW issued an order approving deferral of the incremental solar generation construction costs. The PSCW’s order did not authorize a deferral for the return on such costs. In March 2024, WPL filed for judicial review of the PSCW’s retail electric rate review order (2024/2025 forward-looking Test Period) and solar generation construction cost deferral order related to the recovery and deferral of the return on the incremental solar generation construction costs in 2024 and 2025. Alliant Energy and WPL concluded that there was not a probable disallowance of anticipated higher rate base amounts as of March 31, 2024 given construction costs were reasonably and prudently incurred.