Alliant Energy (LNT) 10-K risk factor changes: FY2023 vs FY2022

A cyber attack may disrupt our operations or lead to a loss or misuse of confidential and proprietary information or potential liability - We operate in an industry that requires the continuous use and operation of [removed: sophisticated] information [removed: technology systems] and [removed: network infrastructure.][added: telecommunications systems.]

We face threats from use of malicious code (such as malware, viruses and ransomware), employee theft or misuse, advanced persistent threats, vulnerabilities [removed: such] [added: (such] as the log4j [removed: vulnerability,] [added: and MOVEit vulnerabilities),] fraud attempts, and phishing attacks.

Due to the evolving nature of cyber attacks and [removed: cyber security,] [added: cybersecurity,] our current safeguards to protect our operating systems and information technology assets may not always be effective.

In addition, we [removed: may] [added: use information technology systems to] collect and retain sensitive information, including personal information about our customers, shareowners and employees.

In some cases, we outsource administration of certain functions to vendors that [added: have been or] could be targets of cyber [added: attacks.]

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Energy demand may decrease due to many things, including [added: economic conditions,] proliferation of customer and third party-owned generation, technological advances that reduce the costs of renewable energy and storage solutions for our customers, government policies, such as the Inflation Reduction Act of [removed: 2022,] [added: 2022 (IRA Act),] which incentivize customer and third party-owned generation, loss of service territory or franchises, energy efficiency measures, technological advances that improve energy efficiency, third-party disrupters, loss of wholesale customers, [added: loss of customers that pursue their own renewable projects to achieve specific sustainability goals, and] the adverse impact of tariffs on our [removed: customers, and economic conditions.][added: customers.]

Our strategy includes large construction projects, which are subject to risks - Our strategy includes constructing renewable generating [added: facilities, energy storage facilities, natural gas-fired generating] facilities and large-scale additions and upgrades to our electric and gas distribution [removed: systems.][added: systems and generating assets.]

Inability to recover costs, or inability to complete projects [added: or recover costs] in a timely manner, could adversely impact our financial condition and results of operations.

The global supply chain has experienced, and is expected to continue to experience, disruptions due to a multitude of factors, such as geopolitical issues, supplier manufacturing constraints, labor issues, transportation issues, resource availability, long lead times, tariffs, tighter credit markets, inflation, [removed: the COVID-19 pandemic] [added: pandemics] and weather.

We face risks associated with operating electric and natural gas infrastructure - The operation of electric generation and distribution infrastructure involves many risks, including start-up risks, breakdown or failure of equipment, fires developing from our power lines, [removed: transformers] [added: transformers, energy storage facilities,] or substations, dam failure at one of our hydroelectric facilities, the dependence on a specific fuel source, including the supply and transportation of fuel, the risk of performance below expected or contracted levels of output or efficiency, [added: members of the] public [added: or contractors coming into contact with our infrastructure, public] and employee safety, operator error and ruptured oil and chemical tanks.

The operation of our natural gas distribution and transportation infrastructure also involves many risks, such as leaks, explosions, mechanical problems, members of the [removed: public and contractors coming into contact with our infrastructure, and employee and public safety.]

[added: The transmission constraints could result in an inability to deliver] electricity from generating facilities, particularly wind [added: and solar] generating facilities, to the national grid, or to access lower cost sources of electricity.

We are also responsible for compliance with new and changing regulatory standards involving safety, reliability and environmental compliance, including regulations under the Pipeline and Hazardous Materials Safety Administration, the Occupational Health and Safety Administration, the North American Electric Reliability Corporation and [added: the Department of Homeland Security] Transportation Security Administration.

Failure to meet our service [removed: obligations] [added: obligations, and failure of IPL’s solar generating facilities to achieve a certain level of output,] could adversely impact our financial condition and results of operations.

Storms or other natural disasters may impact our operations in unpredictable ways - Storms and other natural disasters, including events such as floods, tornadoes, windstorms like the 2020 derecho in Iowa, blizzards, ice storms, extreme hot temperatures, extreme cold temperatures, fires, [added: wildfires,] solar flares or pandemics may adversely impact our ability to generate, purchase or distribute electric energy and gas or obtain fuel or other critical supplies.

Our counterparties to these contracts may not fulfill their obligations to provide natural [removed: gas] [added: gas, coal, financial settlements] or [removed: coal] [added: collateral] to us due to financial or operational problems caused by natural disasters, severe weather, economic conditions, labor shortages, employee strikes, transportation issues, pandemics, physical attacks or cyber attacks.

If we were unable to obtain enough natural gas or coal for our electric generating facilities under our existing contracts, or to obtain electricity under existing or future purchased power agreements, we could be required to purchase natural gas or coal at higher prices, [added: need to secure higher cost delivery of natural gas or coal, be] forced to [added: curtail the operation of our natural gas-fired or coal-fired generating facilities, be forced to] purchase electricity from higher-cost generating resources in the Midcontinent Independent System Operator, Inc. (MISO) energy market and/or [added: be] required to purchase replacement capacity to comply with electric demand planning reserve margins.

[removed: We may not be able to pass on all of the changes in costs to our customers, especially at WPL where we do not have an automatic retail electric fuel cost adjustment] clause to timely recover such costs and where electric fuel cost recovery may be limited if WPL earns in excess of its authorized return on common equity.

Increases in prices and costs due to disruptions that are not recovered in rates [removed: fully,] [added: fully or not recovered] in a timely manner, may adversely impact our financial condition and results of operations.

[removed: In future rate reviews,] IPL and WPL may not receive an adequate amount of rate relief to recover all costs and earn their authorized rates of return, rates may be reduced, rate refunds may be required, rate adjustments may not be approved on a timely basis, costs may not be otherwise recovered through rates, future rates may be temporarily frozen, [added: laws or rules may limit the ability to file rate adjustments or the period covered by a rate adjustment, regulatory decisions may limit the ability to defer recovery of and a return on prudently incurred costs in between rate reviews,] certain rate base items may not receive a full weighted average cost of capital, and authorized rates of return on capital may be reduced.

We are also subject to oversight and monitoring by organizations such as the North American Electric Reliability Corporation, the Midwest Reliability Organization, the Pipeline and Hazardous Materials Safety Administration, MISO and the [added: Department of Homeland Security] Transportation Security Administration.

The impacts on our operations include: our ability to site and construct new [removed: generating] [added: energy] facilities, such as renewable energy [added: or battery storage] projects, and recover associated [removed: costs, including our ability to continue to use a renewable energy rider in Iowa;] [added: costs;] our ability to decommission generating facilities and recover related costs and the remaining carrying value of these facilities and related assets; changes to MISO’s resource adequacy process establishing seasonal 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, to add resources to meet the requirements of MISO’s [removed: new] [added: seasonal resource adequacy] process, or procure capacity [removed: in the market] whereby such costs might not be recovered in rates; the impact of the lack of availability of existing and new generating facilities has on our accredited capacity for such facilities pursuant to MISO’s [removed: new] seasonal resource adequacy process; [added: IPL’s ability to achieve certain aggregate summer capacity factors under] the [added: consumer protection plan for its up to 400 MW of solar generation projects; the] rates paid to transmission operators and how those costs are recovered from customers, including our ability to continue to use a transmission rider in Iowa; our ability to site, construct and recover costs for new natural gas pipelines; our ability to recover costs to upgrade our electric and gas distribution systems; the amount of certain sources of energy we must use, such as renewable sources; our ability to purchase generating facilities and recover the costs associated therewith; our ability to sell utility assets and any conditions placed upon the sale of such assets; our ability to enter into purchased power agreements and recover the costs associated therewith; the allocation of expenditures by transmission companies on transmission network upgrades and our ability to recover costs associated therewith; reliability; safety; the issuance of securities and ability to use other financing arrangements for our renewable energy projects; accounting matters; and transactions between affiliates.

Failure to obtain approvals for any of these matters in a timely manner, or receipt of approvals with uneconomical conditions, may cause us not to pursue the construction of such [removed: projects] [added: projects,] or to record an impairment of our [removed: assets] [added: assets, or may cause a delay in construction of such projects such that we are not able to meet new demand growth,] and may have a material adverse impact on our financial condition and results of operations.

These tax planning strategies and bonus depreciation deductions have [added: reduced taxable income, which in turn has] generated large tax credit carryforwards.

The [removed: Inflation Reduction] [added: IRA] Act [removed: of 2022] allows for the sale or transfer of [added: eligible] renewable tax credits to other taxpayers.

We plan to sell a substantial amount of our eligible renewable tax [removed: credits in future years.][added: credits.]

[removed: If we are unable] [added: The inability] to sell renewable tax credits at reasonable terms, [added: or if renewable tax credits] that [added: we generate or sell are determined to not be eligible or eligible at a different rate,] could materially impact our tax credit carryforward [removed: position.][added: position or result in liability to purchasers of the tax credits.]

[removed: If the tax rates are increased,] we may experience adverse impacts to our financial condition and results of [removed: operations.][added: operations until those rates are reflected in our regulatory filings.]

Our utility business currently operates wind and solar generating facilities, which generate production tax credits [removed: for us] [added: that are eligible] to [removed: use] [added: be used] to reduce our federal tax obligations.

The amount of production tax credits we earn is dependent on the [removed: date the qualifying generating facilities are placed in service, the] level of electricity output generated by our qualifying generating facilities and [added: sold to an unrelated buyer, and the applicable tax credit rate.]

Our [removed: strategic plan includes] [added: utility business is] developing [added: battery] storage facilities, which are expected to generate investment tax credits.

Investment tax credits are dependent on the [removed: date] [added: tax capitalized costs of] the qualifying generating facilities [removed: begin] and [removed: end construction and] the [removed: costs of the qualifying generating facilities.][added: applicable tax credit rate.]

If there is a disagreement on the [removed: dates construction began and ended] [added: qualifying costs] or [added: whether] the [removed: qualifying costs,] [added: facility qualifies for higher levels of investment tax credits,] the amount of investment tax credits awarded may be significantly reduced, possibly adversely impacting our financial condition and results of operations.

The [removed: Inflation Reduction] [added: IRA] Act [removed: of 2022] introduced new labor requirements that are required to qualify for the full value of renewable tax credits.

Failure to meet these requirements on [removed: future] renewable projects [added: that began construction after January 28, 2023] could result in a significant reduction in the amount of renewable tax credits, which could adversely impact our financial condition and results of operations.

Environmental laws and regulations affecting power generation and electric and gas distribution are complex and subject to continued uncertainty and could be changed by the current [added: or future] Presidential [removed: Administration.][added: or Gubernatorial Administrations.]

Actions related to global climate change and reducing greenhouse gas (GHG) emissions could negatively impact us - [removed: Regulators, customers] [added: We have established GHG reduction goals] and [removed: investors] continue to [removed: raise concerns about climate change] [added: review our strategy] and [removed: GHG emissions.][added: our role in supporting the transition to a low-carbon economy.]

We could incur costs or other obligations to comply with future GHG regulations, and could become the target of legal claims or challenges, because generating electricity using fossil fuels emits [removed: CO2 and other] GHGs.

We could face additional pressures from customers, investors or other stakeholders to more rapidly reduce [removed: CO2] [added: GHG] emissions on a voluntary-basis, including faster adoption of lower [removed: CO2] [added: GHG] emitting technologies and management of excess renewable energy credits.

Incidents of ransomware attacks have been increasing in frequency and magnitude.

Emerging artificial intelligence technologies may be used to develop new hacking tools, exploit vulnerabilities, obscure malicious activities, and increase the difficulty detecting threats.

Measures taken to avoid, detect, mitigate or recover from cybersecurity breaches or incidents may be insufficient or become ineffective, and there are no assurances that cybersecurity breaches or incidents will not impact our business, operations and financial condition.

We outsource certain business functions to third-party suppliers and service providers, and substandard performance by those third parties could harm our business, reputation and results of operations.

For example, WPL has notified the PSCW that its solar generating facility developments have exceeded the approved costs.

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public or contractors coming into contact with our infrastructure, and employee and public safety.

Our utility business also operates wind and solar generating facilities that sell electricity in the MISO energy market.

If MISO energy market prices result in unfavorable pricing for wind or solar energy, this may reduce the energy market revenue produced by those facilities and result in higher electricity costs that would need to be recovered from customers.

We may not be able to pass on all of the changes in costs to our customers, especially at WPL where we do not have an automatic retail electric fuel cost adjustment

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Our future plans and existing operations may be impacted by changing expectations, including heightened emphasis on environmental and social justice concerns related to supporting an equitable transition to cleaner energy and a low-carbon economy.

However, the ability to achieve our GHG reduction goals and implement our strategy is subject to uncertainties as to how climate change concerns will ultimately impact us and various factors that may be out of our control.

These uncertainties include transition risks related to laws and regulations, technology and business operations, or economic and market conditions.

In addition, there are physical risks associated with adapting to changing climate conditions and extreme weather events.

Further, assessment of the science to evaluate and limit global temperature rise continues to evolve.

We may not be able to recover all costs for projects to reduce GHG emissions in rates if regulators determine that the pace of GHG emissions efforts or new technologies are not prudent.

The extent of the EPA’s proposed rules to regulate GHG emissions at fossil-fuel fired electric generating units and specific impacts, including state plans to implement the emissions reductions, remains uncertain.

There could also be changes by the current or future Presidential or Gubernatorial Administrations.

Repeal or amendment of the IRA Act, or portions of the IRA Act, could have an adverse impact on our financial condition and results of operations.

If the federal or state tax rates are increased,

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We have seen and anticipate a steady pace of retirements due to our aging workforce.

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More of our workforce is working remotely, which increases the number of devices connected to the internet that impact our operations and increases our cyber security risk.

Incidents of ransomware attacks have been increasing in frequency and magnitude, including the ransomware attack that resulted in the operator of the Colonial Pipeline paying millions of dollars in ransom to hackers as a result of a cyber attack disabling the pipeline for several days in 2021.

attacks.

For example, we outsource administration of our employee health insurance to Anthem, which was the target of a cyber attack in 2014.

The transmission constraints could result in an inability to deliver

This is a new market that will require regulations and guidance from taxing authorities.

It is unclear what terms and pricing the sale of renewable tax credits will require.

sold to an unrelated buyer, and the applicable tax credit rate.

If there is a disagreement on the in-service date, the amount of production tax credits that we can generate may be significantly reduced.

National regulatory action and international regulatory actions continue to evolve.

We are focused on executing a long-term strategy to deliver safe, reliable and affordable energy with lower carbon dioxide (CO2) emissions independent of changing policies and political landscape.

However, it is unclear how these climate change concerns will ultimately impact us.

The EPA’s approach and timing for implementing rules to regulate CO2 emissions at fossil-fuel fired electric generating units remains undecided and subject to litigation and could change in the current Presidential Administration.

in the future in order to successfully implement our strategy.

We have seen an increase in retirements due to our aging workforce and the recent impact of rising interest rates on pension plan benefits.

Critical employees are being hired at a higher cost.

Poor investment returns or lower interest rates may necessitate

In addition, this MDA includes certain financial information for [removed: 2022] [added: 2023] compared to [removed: 2021.][added: 2022.]

Refer to MDA in the combined [removed: 2021] [added: 2022] [Form [removed: 10-K](http://www.sec.gov/Archives/edgar/data/352541/000035254122000020/lnt-20211231.htm)] [added: 10-K](http://www.sec.gov/Archives/edgar/data/352541/000035254123000017/lnt-20221231.htm)] for details on certain financial information for [removed: 2021] [added: 2022] compared to [removed: 2020.][added: 2021.]

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Alliant Energy’s mission is to deliver affordable energy solutions and exceptional service that its customers and [added: the] communities [added: it serves] count on - affordably, safely, reliably, and sustainably.

Alliant Energy’s mission and purpose [removed: is] [added: are] supported by a strategy focused on meeting the evolving expectations of customers while providing an attractive return for investors, and pursuing emerging technologies and safe, sustainable methods of energy production.

Providing affordable energy solutions [removed: to] [added: for] customers - Alliant Energy’s strategy focuses on affordable energy solutions that support retention and growth of its existing customers and attract new customers to its service territories.

[removed: -] [added: As a result,] Alliant [removed: Energy’s Clean] Energy [removed: Blueprint, also known as its cleaner energy strategy, continues to add clean energy resources in Iowa and Wisconsin, which] directly reinvests in the communities [removed: Alliant Energy] [added: it] serves through the addition of skilled jobs, economic development and increased tax revenue.

[added: -] Alliant Energy, IPL and WPL currently expect to utilize various provisions of the Inflation Reduction Act of 2022 to enhance [removed: the] tax benefits expected from [removed: their announced] [added: wind,] solar and battery storage [removed: projects,] [added: projects in Iowa and Wisconsin,] including transferring certain future tax credits from such projects to other corporate taxpayers.

- Reductions in Iowa corporate income tax rates resulting from tax reform enacted in [removed: March] 2022 are expected to provide cost benefits to IPL’s [added: electric and gas] customers in the future.

- IPL maintaining flat base rates for its retail electric and gas customers in [removed: 2021] [added: 2021, 2022] and [removed: 2022.][added: 2023.]

- Significant fuel cost reductions achieved in [removed: 2021 and] [added: 2021,] 2022 [added: and 2023] as a result of shortening the term of IPL’s DAEC PPA by 5 [removed: years.][added: years, and beginning in 2023 with the May 2023 retirement of Lansing.]

- Issuance of new long-term debt at historically low interest rates for IPL ($300 million of 3.1% senior debentures due 2051) and WPL ($300 million of 1.95% green bonds due 2031) in [removed: 2021,] [added: 2021] and WPL ($600 million of 3.95% green bonds due 2032) in 2022.

- Levelized cost recovery mechanism for the remaining net book value of Edgewater Unit 5, which helps reduce customer [removed: costs in 2022 and 2023.][added: costs.]

Making customer-focused investments - Alliant Energy’s strategic priorities include making significant customer-focused investments toward cleaner [removed: energy] and [removed: resilient] [added: more reliable, resilient,] and sustainable customer [added: energy] solutions.

Alliant Energy’s strategy drives a capital allocation process focused on: 1) transitioning its generation portfolio to meet the growing interest of customers for reliable and sustainable sources of energy, 2) upgrading its electric and gas distribution systems to strengthen [removed: safety] [added: safety, reliability] and resiliency, as well as enable distributed energy solutions in its service territories, and 3) enhancing its customers’ and employees’ experience with evolving technology and greater flexibility.

- [removed: Planned development] [added: Development] and acquisition of additional renewable energy, including approximately 1,100 MW of solar generation at WPL with in-service dates in 2022-2024, approximately 275 MW of battery storage at WPL with in-service dates in 2024 and 2025, [added: and] approximately 400 MW of solar generation at IPL with in-service dates in [removed: 2023 and 2024, and approximately 75 MW of battery storage at IPL with in-service dates in] 2024.

In addition, IPL and WPL continue to evaluate additional opportunities to add more renewable generation, including repowering of existing wind farms and additional solar generation and distributed energy resources, including community solar and [added: small-scale] energy storage systems.

- Plans to construct and/or acquire additional renewable, battery and natural gas resources to meet the requirements of MISO’s [removed: new] seasonal resource adequacy process establishing capacity planning reserve margin and capacity accreditation requirements effective with the 2023/2024 MISO Planning Year.

Growing customer demand - Alliant Energy’s strategy supports expanding electric and gas usage in its service territories by promoting electrification initiatives and economic [removed: development in the communities it serves.][added: development.]

- Alliant’s [removed: Energy’s economic development efforts resulted in being] [added: Energy was] named a Top Utility in Economic Development by Site Selection Magazine for the [removed: fourth] [added: fifth] year in a row, and [removed: in 2022 being awarded the Chairman’s Award for Workforce Development Leadership] [added: was named a Top Utility] by [removed: the Center] [added: Business Facilities Magazine] for [removed: Energy Workforce Development.][added: the fourth year in a row.]

- Alliant Energy continues to partner with its commercial and industrial customers to help develop renewable solutions to enhance their sustainability initiatives, including [removed: planned] [added: various customer- and community-hosted] solar facilities in Iowa and Wisconsin.

- Alliant Energy has various development-ready sites throughout Iowa and Wisconsin, including the 1,300-acre Big Cedar Industrial Center Mega-site in Cedar Rapids, Iowa, and the [removed: 730-acre] [added: 465-acre] Prairie View Industrial Center Super Park in Ames, Iowa, which are [removed: rail-served] [added: rail-served,] ready-to-build manufacturing and industrial sites in close proximity to the regional [removed: airport and] [added: airport,] interstate freeways and [removed: access] IPL’s electric services.

[removed: Additionally, the] [added: 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.

[removed: Financial Results Overview -] Alliant Energy’s net income and EPS attributable to Alliant Energy common shareowners were as follows (dollars in millions, except per share amounts):

| Utilities and Corporate Services | | | [removed: $690] [added: $724] | | | | | | [removed: $2.74] [added: $2.86] | | | | | | [removed: $632] [added: $690] | | | | | | [removed: $2.52] [added: $2.74] | | |

| ATC Holdings | | | [removed: 29] [added: 35] | | | | | | [removed: 0.12] [added: 0.14] | | | | | | [removed: 31] [added: 29] | | | | | | 0.12 | | |

| Non-utility and Parent | | | [removed: (33)] [added: (56)] | | | | | | [removed: (0.13)] [added: (0.22)] | | | | | | [removed: (4)] [added: (33)] | | | | | | [removed: (0.01)] [added: (0.13)] | | |

| Alliant Energy Consolidated | | | [removed: $686] [added: $703] | | | | | | [removed: $2.73] [added: $2.78] | | | | | | [removed: $659] [added: $686] | | | | | | [removed: $2.63] [added: $2.73] | | |

Alliant Energy’s Utilities and Corporate Services net income increased by [removed: $58] [added: $34] million in [removed: 2022] [added: 2023] compared to [removed: 2021.][added: 2022.]

The increase was primarily due to higher revenue requirements and AFUDC from [removed: WPL] capital investments and [removed: higher electric] [added: lower other operation] and [removed: gas margins, including the impacts of temperatures.][added: maintenance expenses at IPL and WPL.]

These items were partially offset by higher [added: interest expense, lower retail electric and gas sales primarily due to temperature impacts, and higher] depreciation expense.

Alliant Energy’s Non-utility and Parent net income decreased by [removed: $29] [added: $23] million in [removed: 2022] [added: 2023] compared to [removed: 2021,] [added: 2022,] primarily due to higher [removed: financing expense and the impact of the Iowa state income tax rate change.][added: interest expense.]

| | | | Alliant Energy | | | | | | [removed: | | | | | |] IPL | | | | | | [removed: | | | | | |] WPL | | | [removed: | | | | | | | | | | | | | | | | | | | | | | | |]

| [removed: Other] [added: Changes in other] utility [removed: revenues] | | | [removed: 49 | | | | | | 49 | | | | | | | | | | | | 46 | | | | | | 46 | | | | | | | | | | | | 3] [added: 3] | | | | | | 3 | | | | | | [added: —] | | |

| [removed: Non-utility revenues | | | 93 | | | | | | 83 | | | | | | | | |] [added: Changes in non-utility] | | | [removed: —] [added: (3)] | | | | | | — | | | | | | [removed: | | | | | | — | | | | | |] — | | | [removed: | | | | | |]

| [removed: Taxes] [added: Changes in taxes] other than income [removed: tax expense | | | (110) | | | | | | (104) | | | | | | | | | | | | (57) | | | | | | (55) | | | | | | | | |] [added: taxes] | | | [removed: (47)] [added: (5)] | | | | | | [removed: (45)] [added: —] | | | | | | [added: (5)] | | |

| [removed: Total higher] [added: Changes in] other operation and maintenance [removed: expenses variance] (Refer to [removed: details below)] [added: [details below](#i29dd73abc2114eb3bf707729382758d7_66308))] | | | [removed: (28)] [added: 29] | | | | | | [removed: (7)] [added: 16] | | | | | | [removed: (10)] [added: 7] | | |

| Other | | | [removed: 4] [added: (15)] | | | | | | [removed: (2)] [added: (13)] | | | | | | (2) | | |

| Wholesale | | | [removed: 233] [added: 213] | | | | | | [removed: 187] [added: 233] | | | | | | | | | | | | [removed: 2,866] [added: 2,859] | | | | | | [removed: 2,787] [added: 2,866] | | | | | | | | | | | | N/A | | | | | | N/A | | | | | | N/A | | | | | | N/A | | |

| Bulk power and other | | | [removed: 111] [added: 71] | | | | | | [removed: 56] [added: 111] | | | | | | | | | | | | [removed: 3,734] [added: 4,730] | | | | | | [removed: 3,018] [added: 3,734] | | | | | | | | | | | | N/A | | | | | | N/A | | | | | | N/A | | | | | | N/A | | |

- Alliant Energy’s Clean Energy Blueprint, also known as the roadmap for its transition to cleaner energy, continues to add clean energy resources in Iowa and Wisconsin.

In Wisconsin, WPL completed 639 MW of solar generation in 2023, adding to the 250 MW of solar generation placed in service in 2022, and expects to add another 200 MW of solar generation in 2024, resulting in approximately 1,100 MW of solar generation resources in aggregate.

In Iowa, IPL expects to complete 400 MW of solar generation by the end of 2024.

Completion of these projects is expected to result in approximately 1,500 MW of additional zero-fuel cost solar generation resources for Alliant Energy in aggregate by the end of 2024.

The Inflation Reduction Act of 2022 is expected to result in more cost benefits for IPL’s and WPL’s customers, higher rate base amounts, and improvements in long-term cash flows over the life of the solar, battery storage and wind repowering projects.

Refer to [Note 1(c)](#i1fc9d0e18c654199a6dadea9bc41997a_211) for discussion of $98 million of proceeds from renewable tax credits transferred to other corporate taxpayers in 2023.

- In 2023, the U.S. Department of Energy Office of Clean Energy selected the Columbia Energy Storage Project, a first of its kind in the U.S., 20 MW CO2-based long-duration energy storage system at the retiring coal-fired Columbia site, for award negotiations to receive up to $30 million in grant funding.

Alliant Energy, with support from various project partners, currently expects to submit project plans to the PSCW in 2024 after award negotiations with the DOE are finished.

Any grant proceeds would reduce the cost of the project for WPL’s customers.

- Requested PSCW approval 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.

A decision from the PSCW is currently expected by the second quarter of 2024.

- Improving reliability and resiliency with more underground electric distribution, and enabling distributed energy solutions with higher capacity lines.

Currently, approximately 27% of Alliant Energy’s electric distribution system is underground.

Four such facilities were completed in Wisconsin in 2021 and 2022, and several more are currently planned to be completed in 2024 in Iowa and Wisconsin.

- Installing fiber optic routes between Alliant Energy’s facilities to enhance its communications network to improve resiliency and reliability of, and enable and strengthen, the integrated grid network focused on less densely populated rural areas.

| | | | 2023 | | | | | | | | | | | | 2022 | | | | | | | | |

[Table of C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)

| Revenues: | | | | | | | | | | | | | | | | | |

| Changes in electric utility (Refer to [details below](#i29dd73abc2114eb3bf707729382758d7_66303)) | | | ($76) | | | | | | ($98) | | | | | | $22 | | |

| Changes in gas utility (Refer to [details below](#i29dd73abc2114eb3bf707729382758d7_66304)) | | | (102) | | | | | | (51) | | | | | | (51) | | |

| Changes in total revenues | | | (178) | | | | | | (146) | | | | | | (29) | | |

| Operating expenses: | | | | | | | | | | | | | | | | | |

| Changes in electric production fuel and purchased power (Refer to [details below](#i29dd73abc2114eb3bf707729382758d7_66305)) | | | 94 | | | | | | 101 | | | | | | (8) | | |

| Changes in electric transmission service (Refer to [details below](#i29dd73abc2114eb3bf707729382758d7_66306)) | | | (10) | | | | | | (13) | | | | | | 3 | | |

| Changes in cost of gas sold (Refer to [details below](#i29dd73abc2114eb3bf707729382758d7_66307)) | | | 90 | | | | | | 40 | | | | | | 49 | | |

| Changes in depreciation and amortization (Refer to [Note 2](#i1fc9d0e18c654199a6dadea9bc41997a_250) for discussion of reductions to WPL’s depreciation and amortization expense, which was partially offset by WPL’s solar generation placed in service in 2022) | | | (5) | | | | | | (7) | | | | | | 3 | | |

| Changes in total operating expenses | | | 193 | | | | | | 137 | | | | | | 49 | | |

| Changes in operating income | | | 15 | | | | | | (9) | | | | | | 20 | | |

| Other income and deductions: | | | | | | | | | | | | | | | | | |

| Changes in total other income and deductions | | | (16) | | | | | | 7 | | | | | | 4 | | |

| Changes in income before income taxes | | | (1) | | | | | | (2) | | | | | | 24 | | |

| Changes in net income | | | $17 | | | | | | $6 | | | | | | $30 | | |

[Table of C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)

| | | | 2023 | | | | | | 2022 | | | | | | | | | | | | 2023 | | | | | | 2022 | | | | | | | | | | | | 2023 | | | | | | 2022 | | | | | | 2023 | | | | | | 2022 | | |

| Retail | | | $3,008 | | | | | | $3,019 | | | | | | | | | | | | 24,940 | | | | | | 25,409 | | | | | | | | | | | | $495 | | | | | | $588 | | | | | | 46,405 | | | | | | 55,021 | | |

| | | | $3,345 | | | | | | $3,421 | | | | | | | | | | | | 32,587 | | | | | | 32,071 | | | | | | | | | | | | $540 | | | | | | $642 | | | | | | 161,582 | | | | | | 159,833 | | |

| Retail | | | $1,661 | | | | | | $1,747 | | | | | | | | | | | | 13,909 | | | | | | 14,270 | | | | | | | | | | | | $273 | | | | | | $317 | | | | | | 23,128 | | | | | | 28,492 | | |

| | | | $1,761 | | | | | | $1,859 | | | | | | | | | | | | 16,172 | | | | | | 16,475 | | | | | | | | | | | | $300 | | | | | | $351 | | | | | | 66,360 | | | | | | 71,756 | | |

| Retail | | | $1,347 | | | | | | $1,272 | | | | | | | | | | | | 11,031 | | | | | | 11,139 | | | | | | | | | | | | $222 | | | | | | $271 | | | | | | 23,277 | | | | | | 26,529 | | |

| | | | $1,584 | | | | | | $1,562 | | | | | | | | | | | | 16,415 | | | | | | 15,596 | | | | | | | | | | | | $240 | | | | | | $291 | | | | | | 95,222 | | | | | | 88,077 | | |

| | | | 24 | | | | | |

- In 2022, Alliant Energy’s wind generation was the highest in its history, which resulted in renewable tax credits and fuel cost savings for its customers.

- IPL’s renewable energy rider became effective February 26, 2020, which allows for annual adjustments to electric rates charged to IPL’s retail electric customers for actual renewable energy costs incurred to fund IPL’s 1,000 MW of wind EGUs placed in service in 2019 and 2020, and related tax benefits, including production tax credits, that are provided to its electric customers.

- Providing $35 million of billing credits to IPL’s retail electric customers beginning in the third quarter of 2020 through June 2021, largely driven by Federal Tax Reform benefits for customers.

- Redemption of IPL’s 5.1% cumulative preferred stock in 2021.

- WPL’s completion of new solar generation in Wisconsin in 2022, including 150 MW in Wood County, 50 MW in Richland County, and 50 MW in Rock County.

| | | | 25 | | | | | |

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 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.

| | | | 2022 | | | | | | | | | | | | 2021 | | | | | | | | |

| | | | 26 | | | | | |

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):

| | | | 2022 | | | | | | 2021 | | | | | | | | | | | | 2022 | | | | | | 2021 | | | | | | | | | | | | 2022 | | | | | | 2021 | | | | | | | | |

| Operating income | | | $928 | | | | | | $795 | | | | | | | | | | | | $453 | | | | | | $460 | | | | | | | | | | | | $452 | | | | | | $308 | | | | | | | | |

| Electric utility revenues | | | $3,421 | | | | | | $3,081 | | | | | | | | | | | | $1,859 | | | | | | $1,752 | | | | | | | | | | | | $1,562 | | | | | | $1,329 | | | | | | | | |

| Electric production fuel and purchased power expenses | | | (830) | | | | | | (642) | | | | | | | | | | | | (383) | | | | | | (295) | | | | | | | | | | | | (447) | | | | | | (347) | | | | | | | | |

| Electric transmission service expense | | | (573) | | | | | | (537) | | | | | | | | | | | | (407) | | | | | | (367) | | | | | | | | | | | | (166) | | | | | | (170) | | | | | | | | |

| Utility Electric Margin (non-GAAP) | | | 2,018 | | | | | | 1,902 | | | | | | | | | | | | 1,069 | | | | | | 1,090 | | | | | | | | | | | | 949 | | | | | | 812 | | | | | | | | |

| Gas utility revenues | | | 642 | | | | | | 456 | | | | | | | | | | | | 351 | | | | | | 265 | | | | | | | | | | | | 291 | | | | | | 191 | | | | | | | | |

| Cost of gas sold | | | (389) | | | | | | (258) | | | | | | | | | | | | (206) | | | | | | (149) | | | | | | | | | | | | (183) | | | | | | (109) | | | | | | | | |

| Utility Gas Margin (non-GAAP) | | | 253 | | | | | | 198 | | | | | | | | | | | | 145 | | | | | | 116 | | | | | | | | | | | | 108 | | | | | | 82 | | | | | | | | |

| Other operation and maintenance expenses | | | (704) | | | | | | (676) | | | | | | | | | | | | (369) | | | | | | (362) | | | | | | | | | | | | (278) | | | | | | (268) | | | | | | | | |

| Depreciation and amortization expenses | | | (671) | | | | | | (657) | | | | | | | | | | | | (381) | | | | | | (375) | | | | | | | | | | | | (283) | | | | | | (276) | | | | | | | | |

Operating Income Variances - Variances between periods in operating income for 2022 compared to 2021 were as follows (in millions):

| Total higher (lower) utility electric margin variance (Refer to details below) | | | $116 | | | | | | ($21) | | | | | | $137 | | |

| Total higher utility gas margin variance (Refer to details below) | | | 55 | | | | | | 29 | | | | | | 26 | | |

| Total higher depreciation and amortization expense | | | (14) | | | | | | (6) | | | | | | (7) | | |

| | | | $133 | | | | | | ($7) | | | | | | $144 | | |

| | | | 2022 | | | | | | 2021 | | | | | | | | | | | | 2022 | | | | | | 2021 | | | | | | | | | | | | 2022 | | | | | | 2021 | | | | | | 2022 | | | | | | 2021 | | |

| Retail | | | $3,019 | | | | | | $2,771 | | | | | | | | | | | | 25,409 | | | | | | 25,432 | | | | | | | | | | | | $588 | | | | | | $413 | | | | | | 55,021 | | | | | | 48,179 | | |

| | | | $3,421 | | | | | | $3,081 | | | | | | | | | | | | 32,071 | | | | | | 31,308 | | | | | | | | | | | | $642 | | | | | | $456 | | | | | | 159,833 | | | | | | 147,358 | | |

| Retail | | | $1,747 | | | | | | $1,633 | | | | | | | | | | | | 14,270 | | | | | | 14,283 | | | | | | | | | | | | $317 | | | | | | $237 | | | | | | 28,492 | | | | | | 24,881 | | |

| | | | $1,859 | | | | | | $1,752 | | | | | | | | | | | | 16,475 | | | | | | 16,125 | | | | | | | | | | | | $351 | | | | | | $265 | | | | | | 71,756 | | | | | | 65,619 | | |

| Retail | | | $1,272 | | | | | | $1,138 | | | | | | | | | | | | 11,139 | | | | | | 11,149 | | | | | | | | | | | | $271 | | | | | | $176 | | | | | | 26,529 | | | | | | 23,298 | | |

Alliant Energy’s primary focus is to provide regulated electric and natural gas service to approximately [removed: 995,000] [added: 1,000,000] electric and approximately 425,000 natural gas customers in the Midwest through its two public utility subsidiaries, IPL and WPL.

At December 31, [removed: 2022,] [added: 2023,] IPL supplied electric and natural gas service to approximately 500,000 and 225,000 retail customers, respectively, in Iowa.

At December 31, [removed: 2022,] [added: 2023,] WPL supplied electric and natural gas service to approximately [removed: 495,000] [added: 500,000] and 200,000 retail customers, respectively.

[Table of [removed: Co](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)][added: C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)]

Sheboygan Falls Energy Facility - is a 347 MW, simple-cycle, natural gas-fired EGU near Sheboygan Falls, Wisconsin, which is [added: currently] leased to WPL [removed: for an initial period of 20 years ending in 2025.][added: through 2039.]

Travero - is a diversified supply chain solutions company, including a short-line rail freight service in Iowa; a Mississippi River barge, rail and truck freight terminal in Illinois; freight brokerage services; [added: wind turbine blade recycling services;] and a rail-served warehouse in Iowa.

Employees - At December 31, [removed: 2022,] [added: 2023,] Alliant Energy, IPL and WPL had the following full- and part-time employees:

Diversity, [removed: Equity and] [added: Equity,] Inclusion [removed: (DE&I)] [added: and Belonging (DEI&B)] - A diverse, equitable and inclusive workplace [added: where everyone feels like they belong] is crucial for the success and retention of our employees, to attract future talent and to execute our purpose-driven strategy to serve our customers and build stronger communities.

It is one of our Values - “Care for others: Together we create a workplace where people feel like they belong and can use their unique backgrounds, talents and perspectives to their fullest potential.” Alliant Energy is driven by [removed: DE&I] [added: DEI&B] and believes the achievement of its strategic objectives can only be achieved with a focused and engaged workforce.

Alliant Energy’s corporate officers group currently has approximately [removed: 40%] [added: 44%] gender diversity and [removed: 27%] [added: 25%] ethnic diversity.

Our efforts to create a [removed: diverse] [added: diverse, equitable] and inclusive [removed: workforce] [added: workplace] have focused on reducing bias, building diverse teams, and listening [added: to] and acting on employee feedback, and include:

- Employee Resource Groups that foster a [removed: diverse] [added: diverse, equitable] and inclusive workplace that supports employee well-being while promoting professional development and enhancing community relationships; and

- a [removed: DE&I] [added: DEI&B] Leadership Team that partners with the Human Resources [removed: recruiting] department and hiring managers to attract more diverse applicants that represent the diversity of the communities we serve.

Our [removed: DE&I] [added: DEI&B] initiatives also include a focus on building a diverse Board of Directors.

Our Board currently has approximately [removed: 50%] [added: 40%] gender diversity and 20% ethnic diversity.

Our [removed: 2022 DE&I] [added: 2023 DEI&B] accomplishments include:

- selected for the [removed: 2022] [added: 2023] Bloomberg Gender-Equality Index; [added: and]

- held our [removed: third] [added: fourth] annual Day of Understanding, with [removed: 85%] [added: 88%] voluntary company-wide participation, where leaders facilitated conversations around creating a culture of inclusion and belonging, helping to ensure employees are seen, heard and [removed: valued; and][added: valued.]

These include tuition reimbursement, [added: and] online, instructor-led and on-the-job learning formats, as well as leadership development and succession planning.

[removed: In addition, we have an] [added: Our] apprenticeship program [removed: that] combines supervised, structured on-the-job training with related instruction to produce highly skilled trade and technical [removed: workers.][added: workers, and builds lifetime skills and comprehensive knowledge in the high-demand technical trades necessary for our success.]

The [added: apprenticeship] program gives us the flexibility to tailor training to match our needs - training employees in our facilities, on our equipment, and consistent with our safety standards and employee expectations.

FERC designated North American Electric Reliability [removed: Corporation] [added: Corporation, which also provides oversight of cybersecurity standards,] as the overarching Electric Reliability Organization.

In [removed: 2021, legislation was enacted in Iowa prohibiting] [added: Iowa,] counties and cities [added: are prohibited] from regulating the sale of natural gas and propane, which supports IPL’s ability to provide gas utility service to a diversified base of retail customers and industries.

The IUB must decide on requests for retail rate changes within 10 months of the date of the application for which changes are [removed: filed.][added: filed, subject to certain exceptions.]

[removed: In 2021, the] [added: The] IUB [removed: adopted] [added: has] rules that establish minimum filing requirements for rate reviews using a forward-looking test period, and a related subsequent proceeding review after the close of the forward-looking test period.

Energy Efficiency - In accordance with Iowa law, IPL is required to file an [removed: EEP] [added: energy efficiency plan (EEP)] every five years with the IUB.

[added: If rate-making principles are not] approved by the IUB, IPL may construct the facility, subject to other applicable approvals (such as a GCU Certificate), subject to recovery in future rate reviews.

Electric Generating Unit Environmental Controls Projects \- [added: At its sole discretion,] IPL [removed: is required to] [added: may] submit an updated emissions plan and budget [removed: biennially] to the IUB setting out a multi-year plan and budget for managing regulated emissions from its coal-fired EGUs in a cost-effective manner.

[removed: WPL is not obligated to file] for or accept authorized rate-making principles under Wisconsin law.

Department of Homeland Security Transportation Security Administration - Alliant Energy, IPL and WPL are subject to regulation for physical and [removed: cyber security] [added: cybersecurity] of their natural gas pipeline systems, and are applying, and monitoring for changes to, these requirements to their pipeline systems.

In 2009, the EPA issued a ruling that found GHG emissions contribute to climate [removed: change,] [added: change] and [removed: therefore,] [added: therefore] threaten public health and welfare, which [removed: was] [added: is] the [removed: prerequisite] [added: basis] for implementing CO2 reduction standards under the CAA.

*Clean Air Act Section 111(d)* - In 2015, the EPA issued the Clean Power Plan [added: rule] under Section 111(d) of the CAA to reduce CO2 emissions from existing fossil-fueled EGUs through broad electricity system-wide measures.

This was replaced by the Affordable Clean Energy rule in 2019, to reduce CO2 emissions from existing [removed: coal-fueled] [added: coal-fired] EGUs through heat rate improvements.

In 2021, the U.S. Court of Appeals for the District of Columbia [removed: Circuit] vacated and remanded the Affordable Clean Energy rule to the EPA for reconsideration.

In 2022, the Supreme Court issued a [removed: ruling] [added: decision] limiting the extent of the EPA’s authority under Section 111(d) to emissions reduction technologies and operational improvements.

[removed: The] [added: In May 2023, the] EPA [removed: is working on a new set of] [added: proposed the revised] Section 111(d) [added: rule, which would establish] emission guidelines for states to implement Best System of Emission Reduction standards for GHG emissions from existing fossil-fueled [removed: EGUs, and has stated that it intends to issue a proposed rule in 2023] [added: EGUs] and [removed: a final rule in 2024, although a timeline cannot be predicted with certainty.][added: certain combustion turbines.]

Alliant Energy, IPL and WPL are currently unable to predict with certainty the future outcome or impact of these [removed: matters.][added: standards.]

[added: IPL’s] Marshalltown [added: Generating Station] and [added: WPL’s] West Riverside [added: Energy Center] are [added: currently] subject to the EPA’s Section 111(b) regulation and [removed: have been designed to achieve compliance with] [added: thus would be impacted by] these [added: revised] standards.

[removed: Litigation related to Section 111(b) is suspended while the EPA revises its Section 111(b) regulations, and] [added: As a result,] Alliant [removed: Energy, IPL] [added: Energy] and [removed: WPL] [added: IPL] are currently unable to predict with certainty the [added: future outcome or] impact of these [removed: standards.][added: matters.]

In [removed: 2022,] [added: 2023,] the EPA [removed: proposed] [added: finalized] revisions to the CSAPR state-specific ozone season nitrogen oxides emission caps and utility-specific emission allowances for certain states, including Wisconsin, beginning in 2023.

Refer to [Note 10](#i1fc9d0e18c654199a6dadea9bc41997a_292) for additional information on WPL’s Sheboygan Falls Energy Facility lease.

Development-ready Sites - includes various rail-served and ready-to-build manufacturing and industrial sites throughout Iowa and Wisconsin, with access to various airports, interstate freeways and Alliant Energy’s electric services.

| Alliant Energy | | | 3,281 | | | | | | 1,755 | | | | | | 53% | | |

| IPL | | | 1,116 | | | | | | 774 | | | | | | 69% | | |

| WPL | | | 1,045 | | | | | | 868 | | | | | | 83% | | |

[Table of C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)

- enhanced offerings to support the well-being of employees and their families;

Annually, Alliant Energy awards up to 25 scholarships to children of its current employees and eligible retirees who have achieved excellent records in high school who are pursuing a higher education.

Scholarship award recipients may enroll in any accredited two- or four-year college, university or vocational-technical school in the U.S.

[Table of C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)

As we attract and introduce a diverse pool of candidates to our industry, we have an early careers program that includes apprenticeships, youth programs (high school) and internships (college).

Our programs provide a pipeline of talented students to engage in meaningful, hands-on work experiences.

[Table of C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)

WPL is not obligated to file

[Table of C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)

The proposed requirements would be phased in beginning in 2030.

The EPA also proposed to repeal the Affordable Clean Energy rule.

The EPA’s proposed revised Section 111(d) rule would require states to implement plans to reduce CO2 emissions through various Best System of Emission Reduction standards by applying various measures at affected sources, including retirement, enforceable limits on operational capacity, co-firing with low-GHG fuels, or other technological controls.

State plans must be submitted within 24 months of the final rule’s effective date and are subject to EPA approval.

The proposed standards could impact 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.

In addition, the proposed standards could impact natural gas-fired combustion turbines with a capacity of 300 MW or more, including IPL’s Marshalltown Generating Station and Emery Generating Station, and WPL’s Riverside Energy Center and West Riverside Energy Center.

The proposed standards are currently not expected to impact WPL’s coal-fired Columbia Energy Center or Edgewater Generating Station given current plans to retire these EGUs prior to the proposed 2030 implementation deadline.

The EPA plans to finalize the revised Section 111(d) rule in 2024.

In May 2023, the EPA proposed revised standards under Section 111(b), which would establish CO2 emissions limits from certain new and reconstructed fossil-fueled EGUs and would apply prospectively.

The EPA plans to finalize the revised Section 111(b) rule in 2024.

WPL currently receives, and expects to receive in the future, enough CSAPR emission allowances to ensure ongoing compliance without the need to purchase additional allowances.

The 2023 CSAPR revisions do not currently apply to Iowa; however, Iowa

[Table of C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)

could be included in a future rule.

The 2023 Supplemental Rule proposes to tighten some of the flexibility offered in the 2020 Reconsideration Rule for certain waste streams, while additionally proposing a newly defined legacy wastewater waste stream.

Compliance with the 2023 Supplemental Rule will be determined by each facility’s wastewater discharge permit, and new or revised limits would become effective as soon as possible but no later than December 31, 2029.

In May 2023, the EPA published proposed amendments to the CCR Rule that would 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.

[Table of C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)

industries.

The process changed from a Summer-based annual construct to four distinct seasons.

FERC’s approval also established planning reserve margin requirements for all market participants on a seasonal basis and determined a seasonal accredited capacity value for certain classes of generating resources, including higher accredited capacity for wind generation during the Spring, Fall and Winter seasons and higher accredited capacity for solar generation during the Summer season.

Alliant Energy, IPL and WPL currently plan to construct and/or acquire additional renewable, battery and natural gas resources to meet the requirements of the seasonal resource adequacy process and have reflected the estimated capital expenditures for these projects in the “Generation” lines in the construction and acquisition table in “[Liquidity and Capital Resources](#i1fc9d0e18c654199a6dadea9bc41997a_109).” Seasonal capacity reserve margins are as follows:

| Required installed capacity reserve margin | | | 17.7% | | | | | | 25.2% | | | | | | 49.4% | | | | | | 40.8% | | |

| Required unforced capacity reserve margin | | | 9.0% | | | | | | 14.2% | | | | | | 27.4% | | | | | | 26.7% | | |

[Table of C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)

| Alliant Energy | | | 3,129 | | | | | | 1,692 | | | | | | 54% | | |

| IPL | | | 1,080 | | | | | | 755 | | | | | | 70% | | |

| WPL | | | 1,001 | | | | | | 825 | | | | | | 82% | | |

- Employee Assistance program;

- capturing and acting upon employee feedback through employee sentiment surveys;

- all people-leaders completed training on reducing unconscious bias in the interview process.

Our program builds lifetime skills and comprehensive knowledge in the high-demand technical trades necessary for our success.

Stand-alone battery storage facilities will be considered for advance rate-making principles on a case-by-case basis.

If rate-making principles are not

Through 2023, any such deferral is required to be offset against the remaining net book value of Edgewater Unit 5, which is currently expected to be retired by June 1, 2025.

The EPA is reviewing the Section 111(b) standards, and has stated it intends to issue a proposed rule in 2023 and a final rule in 2024, although a timeline cannot be predicted with certainty.

The proposed rule does not apply to Iowa; however, Iowa could be included in the final rule, which is currently expected in 2023.

Compliance for existing steam-electric generating facilities is determined by each facility’s wastewater discharge permit and will generally be required by December 31, 2025.

Projects required for compliance are facility-specific.

As part of the rule-making process, the EPA is expected to determine whether more stringent limitations and standards are appropriate.

Compliance obligations associated with the CCR Rule may be subject to change due to future EPA CCR Rule updates, on-going litigation related to the CCR Rule, and any actions taken to-date that may be challenged.

The new seasonal capacity reserve margins are as follows:

| Required installed capacity reserve margin | | | 15.9% | | | | | | 25.8% | | | | | | 41.2% | | | | | | 39.3% | | |

| Required unforced capacity reserve margin | | | 7.4% | | | | | | 14.9% | | | | | | 25.5% | | | | | | 24.5% | | |

| Nuclear | | | — | | | | | | — | | | | | | 2,347 | | |

| Other (b) | | | 239 | | | | | | 226 | | | | | | 254 | | |

| Nuclear | | | — | | | | | | — | | | | | | 2,347 | | | | | | N/A | | | | | | N/A | | | | | | N/A | | |

| Other (b) | | | 13 | | | | | | 12 | | | | | | 12 | | | | | | 226 | | | | | | 214 | | | | | | 242 | | |

[Table of [removed: Co](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)][added: C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)]

For the fiscal year ended December 31, [removed: 2022][added: 2023]

[removed: ][added: ]

The aggregate market value of the voting and non-voting common equity held by nonaffiliates as of June 30, [removed: 2022:][added: 2023:]

Alliant Energy Corporation - [removed: $14.7] [added: $13.2] billion

Number of shares outstanding of each class of common stock as of January 31, [removed: 2023:][added: 2024:]

Alliant Energy Corporation, Common Stock, $0.01 par value, [removed: 251,137,522] [added: 256,100,293] shares outstanding

Portions of the Proxy Statement relating to Alliant Energy Corporation’s [removed: 2023] [added: 2024] Annual Meeting of Shareowners are, or will be upon filing with the Securities and Exchange Commission, incorporated by reference into Part III hereof.

| | | | [Item 2. Properties](#i1fc9d0e18c654199a6dadea9bc41997a_70) | | | | | | | | | | | | | | | [removed: [21](#i1fc9d0e18c654199a6dadea9bc41997a_70)] [added: [22](#i1fc9d0e18c654199a6dadea9bc41997a_70)] | | |

| | | | [Item 3. Legal Proceedings](#i1fc9d0e18c654199a6dadea9bc41997a_73) | | | | | | | | | | | | | | | [removed: [23](#i1fc9d0e18c654199a6dadea9bc41997a_73)] [added: [25](#i1fc9d0e18c654199a6dadea9bc41997a_73)] | | |

| | | | [Item 4. Mine Safety Disclosures](#i1fc9d0e18c654199a6dadea9bc41997a_76) | | | | | | | | | | | | | | | [removed: [23](#i1fc9d0e18c654199a6dadea9bc41997a_76)] [added: [25](#i1fc9d0e18c654199a6dadea9bc41997a_76)] | | |

| | | | [Information About Executive Officers](#i1fc9d0e18c654199a6dadea9bc41997a_79) | | | | | | | | | | | | | | | [removed: [23](#i1fc9d0e18c654199a6dadea9bc41997a_79)] [added: [25](#i1fc9d0e18c654199a6dadea9bc41997a_79)] | | |

| [Part II.](#i1fc9d0e18c654199a6dadea9bc41997a_82) | | | [Item 5. Market for Registrants’ Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities](#i1fc9d0e18c654199a6dadea9bc41997a_85) | | | | | | | | | | | | | | | [removed: [24](#i1fc9d0e18c654199a6dadea9bc41997a_85)] [added: [26](#i1fc9d0e18c654199a6dadea9bc41997a_85)] | | |

| | | | [Item 6.](#i1fc9d0e18c654199a6dadea9bc41997a_88) [\[Reserv](#i1fc9d0e18c654199a6dadea9bc41997a_88)[ed](#i1fc9d0e18c654199a6dadea9bc41997a_88)[\]](#i1fc9d0e18c654199a6dadea9bc41997a_88) | | | | | | | | | | | | | | | [removed: [24](#i1fc9d0e18c654199a6dadea9bc41997a_88)] [added: [26](#i1fc9d0e18c654199a6dadea9bc41997a_88)] | | |

| | | | [Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations](#i1fc9d0e18c654199a6dadea9bc41997a_94) | | | | | | | | | | | | | | | [removed: [24](#i1fc9d0e18c654199a6dadea9bc41997a_94)] [added: [27](#i1fc9d0e18c654199a6dadea9bc41997a_94)] | | |

| | | | [Item 7A. Quantitative and Qualitative Disclosures About Market Risk](#i1fc9d0e18c654199a6dadea9bc41997a_127) | | | | | | | | | | | | | | | [removed: [41](#i1fc9d0e18c654199a6dadea9bc41997a_127)] [added: [44](#i1fc9d0e18c654199a6dadea9bc41997a_127)] | | |

| | | | [Item 8. Financial Statements and Supplementary Data](#i1fc9d0e18c654199a6dadea9bc41997a_130) | | | | | | | | | | | | | | | [removed: [41](#i1fc9d0e18c654199a6dadea9bc41997a_130)] [added: [44](#i1fc9d0e18c654199a6dadea9bc41997a_130)] | | |

| | | | | | | [Alliant Energy Corporation](#i1fc9d0e18c654199a6dadea9bc41997a_133) | | | | | | | | | | | | [removed: [42](#i1fc9d0e18c654199a6dadea9bc41997a_133)] [added: [45](#i1fc9d0e18c654199a6dadea9bc41997a_133)] | | |

| | | | | | | [Interstate Power and Light Company](#i1fc9d0e18c654199a6dadea9bc41997a_157) | | | | | | | | | | | | [removed: [48](#i1fc9d0e18c654199a6dadea9bc41997a_157)] [added: [51](#i1fc9d0e18c654199a6dadea9bc41997a_157)] | | |

| | | | | | | [Wisconsin Power and Light Company](#i1fc9d0e18c654199a6dadea9bc41997a_178) | | | | | | | | | | | | [removed: [54](#i1fc9d0e18c654199a6dadea9bc41997a_178)] [added: [57](#i1fc9d0e18c654199a6dadea9bc41997a_178)] | | |

| | | | | | | [Combined Notes to Consolidated Financial Statements](#i1fc9d0e18c654199a6dadea9bc41997a_199) | | | | | | | | | | | | [removed: [60](#i1fc9d0e18c654199a6dadea9bc41997a_199)] [added: [63](#i1fc9d0e18c654199a6dadea9bc41997a_199)] | | |

| | | | | | | | | | [1. Summary of Significant Accounting Policies](#i1fc9d0e18c654199a6dadea9bc41997a_202) | | | | | | | | | [removed: [60](#i1fc9d0e18c654199a6dadea9bc41997a_202)] [added: [63](#i1fc9d0e18c654199a6dadea9bc41997a_202)] | | |

| | | | | | | | | | [2. Regulatory Matters](#i1fc9d0e18c654199a6dadea9bc41997a_250) | | | | | | | | | [removed: [66](#i1fc9d0e18c654199a6dadea9bc41997a_250)] [added: [68](#i1fc9d0e18c654199a6dadea9bc41997a_250)] | | |

| | | | | | | | | | [3. Property, Plant and Equipment](#i1fc9d0e18c654199a6dadea9bc41997a_253) | | | | | | | | | [removed: [70](#i1fc9d0e18c654199a6dadea9bc41997a_253)] [added: [71](#i1fc9d0e18c654199a6dadea9bc41997a_253)] | | |

| | | | | | | | | | [4. Jointly-owned Electric Utility Plant](#i1fc9d0e18c654199a6dadea9bc41997a_256) | | | | | | | | | [removed: [71](#i1fc9d0e18c654199a6dadea9bc41997a_256)] [added: [73](#i1fc9d0e18c654199a6dadea9bc41997a_256)] | | |

| | | | | | | | | | [5. Receivables](#i1fc9d0e18c654199a6dadea9bc41997a_259) | | | | | | | | | [removed: [71](#i1fc9d0e18c654199a6dadea9bc41997a_259)] [added: [73](#i1fc9d0e18c654199a6dadea9bc41997a_259)] | | |

| | | | | | | | | | [6. Investments](#i1fc9d0e18c654199a6dadea9bc41997a_268) | | | | | | | | | [removed: [72](#i1fc9d0e18c654199a6dadea9bc41997a_268)] [added: [74](#i1fc9d0e18c654199a6dadea9bc41997a_268)] | | |

| | | | | | | | | | [7. Common Equity](#i1fc9d0e18c654199a6dadea9bc41997a_274) | | | | | | | | | [removed: [73](#i1fc9d0e18c654199a6dadea9bc41997a_274)] [added: [75](#i1fc9d0e18c654199a6dadea9bc41997a_274)] | | |

| | | | | | | | | | [8. Preferred Stock](#i1fc9d0e18c654199a6dadea9bc41997a_277) | | | | | | | | | [removed: [73](#i1fc9d0e18c654199a6dadea9bc41997a_277)] [added: [75](#i1fc9d0e18c654199a6dadea9bc41997a_277)] | | |

| | | | | | | | | | [9. Debt](#i1fc9d0e18c654199a6dadea9bc41997a_280) | | | | | | | | | [removed: [73](#i1fc9d0e18c654199a6dadea9bc41997a_280)] [added: [75](#i1fc9d0e18c654199a6dadea9bc41997a_280)] | | |

| | | | | | | | | | [10. Leases](#i1fc9d0e18c654199a6dadea9bc41997a_292) | | | | | | | | | [removed: [75](#i1fc9d0e18c654199a6dadea9bc41997a_292)] [added: [78](#i1fc9d0e18c654199a6dadea9bc41997a_292)] | | |

| | | | | | | | | | [11. Revenues](#i1fc9d0e18c654199a6dadea9bc41997a_295) | | | | | | | | | [removed: [76](#i1fc9d0e18c654199a6dadea9bc41997a_295)] [added: [79](#i1fc9d0e18c654199a6dadea9bc41997a_295)] | | |

| | | | | | | | | | [12. Income Taxes](#i1fc9d0e18c654199a6dadea9bc41997a_298) | | | | | | | | | [removed: [77](#i1fc9d0e18c654199a6dadea9bc41997a_298)] [added: [80](#i1fc9d0e18c654199a6dadea9bc41997a_298)] | | |

| | | | | | | | | | [13. Benefit Plans](#i1fc9d0e18c654199a6dadea9bc41997a_301) | | | | | | | | | [removed: [79](#i1fc9d0e18c654199a6dadea9bc41997a_301)] [added: [82](#i1fc9d0e18c654199a6dadea9bc41997a_301)] | | |

| | | | | | | | | | [14. Asset Retirement Obligations](#i1fc9d0e18c654199a6dadea9bc41997a_313) | | | | | | | | | [removed: [88](#i1fc9d0e18c654199a6dadea9bc41997a_313)] [added: [91](#i1fc9d0e18c654199a6dadea9bc41997a_313)] | | |

| | | | | | | | | | [15. Derivative Instruments](#i1fc9d0e18c654199a6dadea9bc41997a_316) | | | | | | | | | [removed: [88](#i1fc9d0e18c654199a6dadea9bc41997a_316)] [added: [91](#i1fc9d0e18c654199a6dadea9bc41997a_316)] | | |

| | | | | | | | | | [16. Fair Value Measurements](#i1fc9d0e18c654199a6dadea9bc41997a_322) | | | | | | | | | [removed: [89](#i1fc9d0e18c654199a6dadea9bc41997a_322)] [added: [92](#i1fc9d0e18c654199a6dadea9bc41997a_322)] | | |

| | | | | | | | | | [17. Commitments and Contingencies](#i1fc9d0e18c654199a6dadea9bc41997a_328) | | | | | | | | | [removed: [92](#i1fc9d0e18c654199a6dadea9bc41997a_328)] [added: [94](#i1fc9d0e18c654199a6dadea9bc41997a_328)] | | |

| | | | | | | | | | [18. Segments of Business](#i1fc9d0e18c654199a6dadea9bc41997a_352) | | | | | | | | | [removed: [94](#i1fc9d0e18c654199a6dadea9bc41997a_352)] [added: [97](#i1fc9d0e18c654199a6dadea9bc41997a_352)] | | |

| | | | | | | | | | [19. Related Parties](#i1fc9d0e18c654199a6dadea9bc41997a_355) | | | | | | | | | [removed: [96](#i1fc9d0e18c654199a6dadea9bc41997a_355)] [added: [99](#i1fc9d0e18c654199a6dadea9bc41997a_355)] | | |

Interstate Power and Light Company ☐

Wisconsin Power and Light Company ☐

[Table of C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)

| | | | [Item 1](#i1fc9d0e18c654199a6dadea9bc41997a_3381)[C](#i1fc9d0e18c654199a6dadea9bc41997a_3381)[.](#i1fc9d0e18c654199a6dadea9bc41997a_3381) [Cybe](#i1fc9d0e18c654199a6dadea9bc41997a_3381)[r](#i1fc9d0e18c654199a6dadea9bc41997a_3381)[s](#i1fc9d0e18c654199a6dadea9bc41997a_3381)[ec](#i1fc9d0e18c654199a6dadea9bc41997a_3381)[urity](#i1fc9d0e18c654199a6dadea9bc41997a_3381) | | | | | | | | | | | | | | | [21](#i1fc9d0e18c654199a6dadea9bc41997a_3381) | | |

[Table of C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)

| AEF | | | Alliant Energy Finance, LLC | | | GHG | | | Greenhouse gases | | |

| Alliant Energy | | | Alliant Energy Corporation | | | IRS | | | Internal Revenue Service | | |

| ARO | | | Asset retirement obligation | | | ITC | | | ITC Midwest LLC | | |

| CA | | | Certificate of authority | | | MGP | | | Manufactured gas plant | | |

| CO2 | | | Carbon dioxide | | | MWh | | | Megawatt-hour | | |

| CSAPR | | | Cross-State Air Pollution Rule | | | OIP | | | Alliant Energy Omnibus Incentive Plan | | |

| CWIP | | | Construction work in progress | | | OPEB | | | Other postretirement benefits | | |

| DAEC | | | Duane Arnold Energy Center | | | PPA | | | Purchased power agreement | | |

| EGU | | | Electric generating unit | | | SEC | | | Securities and Exchange Commission | | |

| EPA | | | U.S. Environmental Protection Agency | | | U.S. | | | United States of America | | |

| Financial Statements | | | Consolidated Financial Statements | | | West Riverside | | | West Riverside Energy Center and Solar Facility | | |

| Fuel-related | | | Electric production fuel and purchased power | | | WPL | | | Wisconsin Power and Light Company | | |

- economic conditions in IPL’s and WPL’s service territories;

[Table of C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)

- the ability to obtain deferral treatment for the recovery of and a return on prudently incurred costs in between rate reviews;

- WPL’s ability to obtain adequate and timely rate relief to allow for the recovery of and/or the return on costs of solar generation projects that exceed initial cost estimates;

- the future development of technologies related to electrification, and the ability to reliably store and manage electricity;

- 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;

[Table of C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)

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 by reference.

| 2023 Alliant Energy Proxy Statement | | | Alliant Energy’s Proxy Statement for the 2023 Annual Meeting of Shareowners | | | Fuel-related | | | Electric production fuel and purchased power | | |

| ARO | | | Asset retirement obligation | | | IRS | | | Internal Revenue Service | | |

| ATI | | | AE Transco Investments, LLC | | | KWh | | | Kilowatt-hour | | |

| CA | | | Certificate of authority | | | Marshalltown | | | Marshalltown Generating Station | | |

| COVID-19 | | | Novel coronavirus | | | MWh | | | Megawatt-hour | | |

| CSAPR | | | Cross-State Air Pollution Rule | | | Note(s) | | | Combined Notes to Consolidated Financial Statements | | |

| CWIP | | | Construction work in progress | | | OIP | | | Alliant Energy Omnibus Incentive Plan | | |

| DAEC | | | Duane Arnold Energy Center | | | OPEB | | | Other postretirement benefits | | |

| Dth | | | Dekatherm | | | PSCW | | | Public Service Commission of Wisconsin | | |

| EGU | | | Electric generating unit | | | Riverside | | | Riverside Energy Center | | |

| EPA | | | U.S. Environmental Protection Agency | | | SEC | | | Securities and Exchange Commission | | |

| Federal Tax Reform | | | Tax Cuts and Jobs Act | | | VEBA | | | Voluntary Employees’ Beneficiary Association | | |

We operate in an industry that requires the continuous use and operation of information and telecommunications systems.

In addition, we use information technology systems to collect and retain sensitive information, including confidential and proprietary information about our businesses, and personal information about our customers, shareowners and employees.

Cybersecurity risks are identified through the enterprise risk management (ERM) program as key risks we face.

These risks could include use of malicious code, employee theft or misuse, advanced persistent threats, vulnerabilities, fraud attempts, and phishing attacks that could cause, among others, an information technology system failure, or breach or loss of sensitive information.

The potential impact of cybersecurity risks on our business operations, results of operations or financial condition is discussed in the “[R](#i75cad01f8ae347fd85f089759fc390bd_143766)[i](#i75cad01f8ae347fd85f089759fc390bd_143766)[sks R](#i75cad01f8ae347fd85f089759fc390bd_143766)[elated to Business Operations](#i75cad01f8ae347fd85f089759fc390bd_143766)” section of Item 1A “[Risk Factors](#i1fc9d0e18c654199a6dadea9bc41997a_64).” We have not had any material cybersecurity breaches or incidents and have not incurred any material expenses, penalties or settlement costs related to any cybersecurity breaches or incidents.

However, measures that we take to avoid, detect, mitigate or recover from cybersecurity breaches or incidents may be insufficient or become ineffective, and there are no assurances that cybersecurity breaches or incidents will not impact our business operations and strategy, results of operations and financial condition.

We maintain a cybersecurity program that includes development and implementation of policies, procedures and tools designed to help ensure availability of critical information technology and telecommunication systems and safeguard sensitive information.

The cybersecurity program is assessed against industry standards, including the Center for Internet Security critical security controls.

This assessment is conducted by a third party periodically and internally at least annually.

We are also required to comply with cybersecurity standards under the North American Electric Reliability Corporation (NERC) Critical Infrastructure Protection and by the Department of Homeland Security Transportation Security Administration.

We also periodically collaborate with law enforcement experts, external assessors, consultants, industry peers and other third parties in connection with understanding market and threat conditions used to identify, assess and mitigate cybersecurity risks.

| | | | | | | | | |

| --- | --- | --- | --- | --- | --- | --- | --- | --- |

| | | | 21 | | | | | |

[Table of C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)

The cybersecurity program includes:

- a dedicated cybersecurity team;

- information technology and telecommunication systems implemented with segmentation and multiple levels of access controls;

- a security operations center that continuously monitors information technology and telecommunications systems;

- an incident response team composed of individuals from the information technology, operations, accounting, finance, legal, and communications departments, as needed, which is activated to respond to cybersecurity incidents;

- periodic drills and exercises to address risks and prepare for extraordinary scenarios, including industry collaboration on incident preparation, such as GridEx drills hosted by NERC, participation in a full activation drill at least annually, and several tabletop drills during the year;

- periodic drills with the full executive team, including the Chief Executive Officer (CEO), Chief Financial Officer (CFO), Chief Accounting Officer (CAO), Chief Information Officer (CIO) and General Counsel;

- periodic information security awareness training and phishing simulations for employees and contractors who access our networks;

- periodic security assessments of evolving risks and threats that lead to strengthening of cybersecurity measures;

- implementation of automation solutions to strengthen detection and response capabilities; and

- maintenance of cyber liability insurance.

We also address cybersecurity risks associated with third-party service providers, including those in our supply chain or who have access to our customer and employee data or our information technology systems.

Third-party risks are included in the ERM program and the cybersecurity program.

Diligence is performed on third parties that have access to information technology systems, data or facilities that house such systems or data.

High-risk vendors are identified and continually monitored for cybersecurity threat risks.

Additionally, third parties that have access to information technology systems, data or facilities that house such systems or data, agree by contract to manage their cybersecurity risks, provide notification in the event of a cybersecurity incident, and be subject to cybersecurity audits.

Our cybersecurity program is overseen by our Senior Vice President and CIO, who has nearly two decades of experience in information technology, having previously held CIO roles with other organizations, as well as experience in the utility sector.

The CIO oversees a team dedicated to the support of cybersecurity tools and the overall cybersecurity program.

The CIO reports to the Executive Vice President and CFO.

The CIO provides periodic briefs regarding prevention, detection, mitigation and remediation of cybersecurity incidents, as well as risks, threats and the threat landscape to the Board and executive management, including the CEO, CFO and CAO.

These briefs are used to help continuously improve our cybersecurity program and to inform risk assessments as part of the ERM program.

The full Board of Directors is responsible for oversight of our key cybersecurity risks.

The Board retains direct oversight of cybersecurity matters to best utilize the experiences and expertise of all Board members.

Management, including the CIO, provides reports approximately quarterly to the Board regarding risks, threats, the threat landscape, assessments of and improvements to the cybersecurity program and internal response preparedness.

Electric - At December 31, [removed: 2022,] [added: 2023,] IPL’s and WPL’s facilities by primary fuel type were as follows:

| Marshalltown Generating Station (Units 1-3); Marshalltown, IA | | | | | | | | | | | | 2017 | | | | | | | | | | | | | | | | | | [removed: 528] [added: 656] | | |

| Emery Generating Station (Units 1-3); Mason City, IA | | | | | | | | | | | | 2004 | | | | | | | | | | | | | | | | | | [removed: 514] [added: 533] | | |

| Burlington Generating Station (Unit 1); Burlington, IA | | | | | | | | | | | | 1968 | | | | | | | | | | | | | | | | | | [removed: 162] [added: 160] | | |

| Marshalltown Combustion Turbines (Units 1-3); Marshalltown, IA | | | | | | | | | | | | 1978 | | | | | | | | | | | | | | | | | | [removed: 141] [added: 162] | | |

| Prairie Creek Generating Station (Unit 4); Cedar Rapids, IA | | | | | | | | | | | | 1967 | | | | | | | | | | | | | | | | | | [removed: 99] [added: 114] | | |

| Burlington Combustion Turbines (Units 1-4); Burlington, IA | | | | | | | | | | | | 1994-1996 | | | | | | | | | | | | | | | | | | [removed: 32] [added: 36] | | |

| Total Gas | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [removed: 1,476] [added: 1,661] | | |

| Ottumwa Generating Station (Unit 1); Ottumwa, IA (b) | | | | | | | | | | | | 1981 | | | | | | | | | | | | | | | | | | [removed: 309] [added: 348] | | |

| George Neal Generating Station (Unit 4); Sioux City, IA (c) | | | | | | | | | | | | 1979 | | | | | | | | | | | | | | | | | | [removed: 158] [added: 166] | | |

| George Neal Generating Station (Unit 3); Sioux City, IA (d) | | | | | | | | | | | | 1975 | | | | | | | | | | | | | | | | | | [removed: 137] [added: 143] | | |

| Prairie Creek Generating Station (Units 1 and 3); Cedar Rapids, IA | | | | | | | | | | | | 1958-1997 | | | | | | | | | | | | | | | | | | [removed: 31] [added: 36] | | |

| Louisa Generating Station (Unit 1); Louisa, IA (e) | | | | | | | | | | | | 1983 | | | | | | | | | | | | | | | | | | [removed: 29] [added: 30] | | |

| Total Coal | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [removed: 810] [added: 723] | | |

| Lime Creek Combustion Turbines (Units 1-2); Mason City, IA | | | | | | | | | | | | 1991 | | | | | | | | | | | | | | | | | | [removed: 63] [added: 71] | | |

| Total Oil | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [removed: 63] [added: 71] | | |

| Total Battery Storage | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [removed: 4] [added: 9] | | |

| Total capacity | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [removed: 3,663] [added: 3,774] | | |

[Table of [removed: Co](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)][added: C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)]

| Riverside Energy Center (Units 1-3); Beloit, WI | | | | | | | | | | | | 2004 | | | | | | | | | | | | | | | | | | [removed: 438] [added: 530] | | |

| West Riverside Energy Center (Units 1-3); Beloit, WI (f) | | | | | | | | | | | | 2020 | | | | | | | | | | | | | | | | | | [removed: 436] [added: 508] | | |

| Neenah Energy Facility (Units 1-2); Neenah, WI | | | | | | | | | | | | 2000 | | | | | | | | | | | | | | | | | | [removed: 289] [added: 299] | | |

| South Fond du Lac Combustion Turbines (2 Units); Fond du Lac, WI (g) | | | | | | | | | | | | 1994 | | | | | | | | | | | | | | | | | | [removed: 162] [added: 164] | | |

| Total Gas | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [removed: 1,325] [added: 1,501] | | |

| Columbia Energy Center (Units 1-2); Portage, WI (i) | | | | | | | | | | | | 1975-1978 | | | | | | | | | | | | | | | | | | [removed: 584] [added: 606] | | |

| Edgewater Generating Station (Unit 5); Sheboygan, WI | | | | | | | | | | | | 1985 | | | | | | | | | | | | | | | | | | [removed: 356] [added: 406] | | |

| Total Coal | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [removed: 940] [added: 1,012] | | |

| West Riverside Solar Facility, Beloit, WI [removed: (j)] [added: (f)] | | | | | | | | | | | | 2021 | | | | | | | | | | | | | | | | | | [removed: 4] [added: 3] | | |

| Total Solar | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [removed: 258] [added: 896] | | |

| Prairie du Sac Hydro Plant (8 Units); Prairie due Sac, WI | | | | | | | | | | | | 1914-1940 | | | | | | | | | | | | | | | | | | [removed: 13] [added: 17] | | |

| Kilbourn Hydro Plant (4 Units); Wisconsin Dells, WI | | | | | | | | | | | | 1926-1939 | | | | | | | | | | | | | | | | | | [removed: 6] [added: 7] | | |

| Total Hydro | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [removed: 19] [added: 24] | | |

| Battery Storage; [removed: Portage,] [added: various locations in] WI | | | | | | | | | | | | [removed: 2022] [added: 2022-2023] | | | | | | | | | | | | | | | | | | [removed: 5] [added: 9] | | |

| Total Battery Storage | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [removed: 5] [added: 9] | | |

| Total capacity | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [removed: 3,027] [added: 3,922] | | |

(a)Based on the [removed: accredited] [added: summer installed] generating capacity included in MISO’s resource adequacy process for the planning period from June [removed: 2022] [added: 2023] through May [removed: 2023,] [added: 2024,] except for wind facilities, solar facilities and battery storage, which are based on nameplate capacity.

(f)Represents WPL’s [removed: 91%] [added: 73.8%] ownership interest, which is operated by WPL.

Corporate Services - Corporate Services’ property included in “Property, plant and equipment, net” on Alliant Energy’s balance sheet at December 31, [removed: 2022] [added: 2023] consisted primarily of [removed: a customer billing and information system for IPL and WPL and other] computer software, and the corporate headquarters building located in Madison, Wisconsin.

AEF - AEF’s principal properties included in “Property, plant and equipment, net” on Alliant Energy’s balance sheet at December 31, [removed: 2022] [added: 2023] were as follows:

The [removed: Sheboygan Falls Energy Facility was accredited with 291 MW of] [added: summer installed] generating capacity [removed: for] [added: included in] MISO’s resource adequacy process for the planning period from June [removed: 2022] [added: 2023] through May [removed: 2023.][added: 2024 for the Sheboygan Falls Energy Facility was 297 MW.]

| Battery Storage; various locations in IA | | | | | | | | | | | | 2019-2023 | | | | | | | | | | | | | | | | | | 9 | | |

| | | | 23 | | | | | |

[Table of C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)

| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |

| Onion River Solar Facility, Sheboygan Co., WI | | | | | | | | | | | | 2023 | | | | | | | | | | | | | | | | | | 150 | | |

| Springfield Solar Facility, Dodge Co., WI | | | | | | | | | | | | 2023 | | | | | | | | | | | | | | | | | | 100 | | |

| Wautoma Solar Facility, Waushara Co., WI | | | | | | | | | | | | 2023 | | | | | | | | | | | | | | | | | | 99 | | |

| Crawfish River Solar Facility, Jefferson Co., WI | | | | | | | | | | | | 2023 | | | | | | | | | | | | | | | | | | 75 | | |

| Paddock Solar Facility, Rock Co., WI | | | | | | | | | | | | 2023 | | | | | | | | | | | | | | | | | | 65 | | |

| Albany Solar Facility, Green Co., WI | | | | | | | | | | | | 2023 | | | | | | | | | | | | | | | | | | 50 | | |

| Beaver Dam Solar Facility, Dodge Co., WI | | | | | | | | | | | | 2023 | | | | | | | | | | | | | | | | | | 50 | | |

| Cassville Solar Facility, Grant Co., WI | | | | | | | | | | | | 2023 | | | | | | | | | | | | | | | | | | 50 | | |

| | | | | | | | | |

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Development-ready Sites - includes various rail-served and ready-to-build manufacturing and industrial sites throughout Iowa and Wisconsin, with access to various airports, interstate freeways and Alliant Energy’s electric services.

| Lansing Generating Station (Unit 4); Lansing, IA | | | | | | | | | | | | 1977 | | | | | | | | | | | | | | | | | | 146 | | |

| Battery Storage; Decorah, Wellman and Marshalltown, IA | | | | | | | | | | | | 2019-2021 | | | | | | | | | | | | | | | | | | 4 | | |

| | | | 21 | | | | | |

(j)Represents WPL’s 91% ownership interest, which is operated by WPL.

The executive officers of Alliant Energy, IPL and WPL [removed: announced] as of the date of this filing are as follows:

| John O. Larsen | | | | | | [removed: 59] [added: 60] | | | | | | Alliant Energy | | | | | | Mr. Larsen has served as a director since February 2019, and as [added: Executive Chairman and Chairman of the Board since January 2024. He previously served as] Chair of the [removed: Board, President] [added: Board] and Chief Executive Officer (CEO) since [added: February 2023, as Chair of the Board, President and CEO from] July [removed: 2019. He previously served] [added: 2019 to February 2023, and] as President and Chief Operating Officer (COO) [removed: since January 2019, and as President] from January [removed: 2018] [added: 2019] to [removed: January] [added: July] 2019. [removed: Mr. Larsen’s service as President will end in February 2023 with the effectiveness of Ms. Barton’s appointment.] | | |

| | | | | | | | | | | | | IPL [added: and WPL] | | | | | | Mr. Larsen has served as [removed: CEO since January 2019, as] a director since February 2019, and as [removed: Chair] [added: Executive Chairman and Chairman] of the Board since [removed: July 2019.] [added: January 2024.] He previously served as [removed: Senior Vice President (VP)] [added: Chair of the Board] since [removed: February 2014. Mr. Larsen’s service] [added: July 2019, and] as CEO [removed: will end in] [added: from January 2019 to] February [removed: 2023 with the effectiveness of Ms. Barton’s appointment.] [added: 2023.] | | |

| Lisa M. Barton | | | | | | [removed: 57] [added: 58] | | | | | | Alliant Energy | | | | | | Ms. Barton [removed: was selected to become] [added: has served as] President and [removed: COO effective February 27, 2023.] [added: CEO and as a director since January 2024.] She previously served as [added: President and COO since February 2023, as] Executive [removed: VP] [added: Vice President (VP)] and COO of American Electric Power Company, Inc. (AEP) from January 2021 to November 2022, [added: as] Executive VP - Utilities of AEP from January 2020 to December 2020, and as Executive VP - Transmission of AEP from 2011 to 2019. | | |

| Robert J. Durian | | | | | | [removed: 52] [added: 53] | | | | | | Alliant Energy, IPL and WPL | | | | | | Mr. Durian has served as Executive VP and Chief Financial Officer (CFO) since February 2020. He previously served as Senior VP and CFO since February 2019; and as Senior VP, CFO and Treasurer from January 2018 to February 2019. | | |

[Table of [removed: Co](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)][added: C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)]

| David A. de Leon | | | | | | [removed: 60] [added: 61] | | | | | | Alliant Energy and IPL | | | | | | Mr. de Leon has served as Senior VP since January 2019. [removed: He previously served as VP since April 2017.] | | |

| | | | | | | | | | | | | WPL | | | | | | Mr. de Leon has served as President since January 2019. [removed: He previously served as VP since April 2017.] | | |

| Terry L. Kouba | | | | | | [removed: 64] [added: 65] | | | | | | Alliant Energy and WPL | | | | | | Mr. Kouba has served as Senior VP since January 2019. [removed: He previously served as VP since February 2014.] [added: Mr. Kouba plans to retire effective May 1, 2024.] | | |

| | | | | | | | | | | | | IPL | | | | | | Mr. Kouba has served as President since January 2019. [removed: He previously served as VP since February 2014.] | | |

| | | | | | | | | | | | | IPL and WPL | | | | | | Ms. Barton has served as CEO since February 2023, and as a director since January 2024. | | |

| | | | 25 | | | | | |

| Mayuri N. Farlinger | | | | | | 41 | | | | | | Alliant Energy and WPL | | | | | | Ms. Farlinger has served as Vice President since January 2022. She previously served as Director of Operations from January 2020 to December 2021, as Director of Revenue Management from February 2019 to January 2020, and as Manager - Customer Support Center, Billing Integrity from May 2018 to February 2019. | | |

| | | | | | | | | | | | | IPL | | | | | | Ms. Farlinger has served as Vice President since January 2022. She was selected to become President of IPL effective May 1, 2024. | | |

| Raja Sundararajan | | | | | | 49 | | | | | | Alliant Energy, IPL and WPL | | | | | | Mr. Sundararajan has served as Executive VP since June 2023. He previously served as Executive VP - External Affairs of AEP since July 2022, as Senior VP - Regulatory and Customer Solutions of AEP from July 2021 to July 2022, and as President and COO of AEP Ohio from January 2019 to July 2021. | | |

| | | | | | | | | | | | | WPL | | | | | | Mr. Larsen has served as CEO since January 2019, as a director since February 2019, and as Chair of the Board since July 2019. He previously served as President since December 2010. Mr. Larsen’s service as CEO will end in February 2023 with the effectiveness of Ms. Barton’s appointment. | | |

| | | | | | | | | | | | | IPL and WPL | | | | | | Ms. Barton was selected to become CEO effective February 27, 2023. | | |

| | | | 23 | | | | | |

| Michael Luhrs | | | | | | 50 | | | | | | Alliant Energy, IPL and WPL | | | | | | Mr. Luhrs has served as Senior VP since April 2022. He previously was with Duke Energy, Inc. as VP - Integrated Grid Strategy and Solutions from 2021 to 2022, VP - Market Strategy and Solutions from 2019 to 2021, and as VP - Retail Programs from 2013 to 2018. | | |

Common Stock Data - Alliant Energy’s common stock trades on the Nasdaq Global Select Market under the symbol “LNT,” and the closing sales price at December 31, [removed: 2022] [added: 2023] was [removed: $55.21.][added: $51.30.]

Shareowners - At December 31, [removed: 2022,] [added: 2023,] there were [removed: 21,556] [added: 20,547] holders of record of Alliant Energy’s common stock, including holders through Alliant Energy’s Shareowner Direct Plan.

Dividends - In November [removed: 2022,] [added: 2023,] Alliant Energy announced an increase in its targeted [removed: 2023] [added: 2024] annual common stock dividend to [removed: $1.81] [added: $1.92] per share, which is equivalent to a quarterly rate of [removed: $0.4525] [added: $0.48] per share, beginning with the February [removed: 2023] [added: 2024] dividend payment.

Common Stock Repurchases - A summary of Alliant Energy common stock repurchases for the quarter ended December 31, [removed: 2022] [added: 2023] was as follows:

| October 1 to October 31 | | | | | | 5,338 | | | | | | $49.75 | | | | | | — | | | | | | N/A | | |

| November 1 to November 30 | | | | | | 3,685 | | | | | | 49.32 | | | | | | — | | | | | | N/A | | |

| December 1 to December 31 | | | | | | 25 | | | | | | 51.16 | | | | | | — | | | | | | N/A | | |

| | | | | | | 9,048 | | | | | | 49.58 | | | | | | — | | | | | | | | |

| October 1 to October 31 | | | | | | 5,101 | | | | | | $50.28 | | | | | | — | | | | | | N/A | | |

| November 1 to November 30 | | | | | | 3,224 | | | | | | 53.66 | | | | | | — | | | | | | N/A | | |

| December 1 to December 31 | | | | | | 43 | | | | | | 55.30 | | | | | | — | | | | | | N/A | | |

| | | | | | | 8,368 | | | | | | 51.61 | | | | | | — | | | | | | | | |

| | | | | | | | | |

| --- | --- | --- | --- | --- | --- | --- | --- | --- |

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[Table of [removed: Co](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)][added: C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)]

We have audited the accompanying consolidated balance sheets of Alliant Energy Corporation and subsidiaries (the “Company”) as of December 31, [removed: 2022] [added: 2023] and [removed: 2021,] [added: 2022,] the related consolidated statements of income, equity, and cash flows, for each of the three years in the period ended December 31, [removed: 2022,] [added: 2023,] and the related notes and the schedules listed in the Index at Item 15 (collectively referred to as the “financial statements”).

In our opinion, the financial statements present fairly, in all material respects, the financial position of the Company as of December 31, [removed: 2022] [added: 2023] and [removed: 2021,] [added: 2022,] and the results of its operations and its cash flows for each of the three years in the period ended December 31, [removed: 2022,] [added: 2023,] in conformity with accounting principles generally accepted in the United States of America.

We have also audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the Company’s internal control over financial reporting as of December 31, [removed: 2022,] [added: 2023,] based on criteria established in *Internal Control - Integrated Framework (2013)* issued by the Committee of Sponsoring Organizations of the Treadway Commission and our report dated February [removed: 24, 2023,] [added: 16, 2024,] expressed an unqualified opinion on the Company’s internal control over financial reporting.

Regulatory [removed: Assets and Regulatory Liabilities] [added: Accounting] - Impact of rate regulation on the financial statements - Refer to Notes 1, 2, and 3 to the financial statements

Alliant Energy Corporation, through its wholly-owned subsidiaries Interstate Power and Light Company and Wisconsin Power and Light Company, is subject to rate regulation by [removed: the Federal Energy Regulatory Commission and the respective state commissions in Iowa and Wisconsin (collectively the “regulatory agencies”).][added: regulatory agencies.]

A change in these rulings may result in a material impact on results of operations and the amount of [added: certain] assets and liabilities in the financial statements.

Future regulatory rulings may impact the carrying value and accounting treatment of [removed: the] [added: certain] regulatory assets and regulatory liabilities.

We identified the impact of rate regulation as a critical audit matter due to the significant judgments made by management to support its assertions about [added: certain] impacted account balances and disclosures and the high degree of subjectivity involved in assessing the impact of [added: relevant] future regulatory orders on the financial statements.

- We tested the effectiveness of management’s controls over the evaluation of [removed: the likelihood of recovery in future customer rates for] [added: certain] regulatory assets and [removed: the likelihood of a probable refund to customers or reduction in future customer rates for] regulatory [removed: liabilities; and] [added: liabilities, including] the monitoring and evaluation of regulatory developments that may affect the likelihood of recovering costs in future rates or of a future reduction in rates.

- We [removed: obtained] [added: inspected and evaluated] the Company’s analysis supporting the probability of recovery for [added: certain] regulatory assets or refund to customers or future reduction in customer rates for regulatory liabilities not yet addressed in a regulatory order to assess management’s [removed: assertion that amounts are probable of recovery in future customer rates or represent a probable refund to customers or reduction in future customer rates.][added: assertions.]

- We inquired of management regarding current events impacting the Company and inspected minutes of the board of directors and other committees of the Company and evaluated whether matters were identified that may have an impact on [added: certain] recorded regulatory [removed: asset] [added: assets] and [removed: liability balances.][added: liabilities.]

- We read relevant regulatory [removed: orders issued by the regulatory agencies for the Company and other relevant public utilities, regulatory statutes,] [added: orders,] interpretations, [removed: procedural memorandums,] filings made by [removed: certain] [added: the Company or its] stakeholders, and other publicly available information [removed: to assess the likelihood of recovery in future customer rates based on precedents of] [added: issued by] the regulatory [removed: agencies’ treatment of similar costs under similar circumstances.][added: agencies that pertain to the Company.]

We evaluated the external information and [added: assessed] whether there [removed: were] [added: are] matters in such information that would be contradictory to [removed: the assessment] [added: management’s assertion] of [added: probability of] recovery of [removed: the Company’s] [added: certain] regulatory assets or refund of regulatory liabilities.

[added: -] We inspected minutes of the board of directors and other committees of the Company, regulatory orders and other filings with the regulatory agencies to identify evidence that may contradict management’s assertion regarding probability of [removed: an] abandonment or that may have an impact on the recorded balances.

- We evaluated the Company’s disclosures related to the impacts of rate regulation and regulatory developments, including [removed: the] [added: disclosures related to certain] regulatory balances recorded.

[removed: February 24, 2023][added: | 2023: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |]

| | | | [removed: 2022] [added: 2023] | | | | | | [removed: 2021] [added: 2022] | | | | | | [removed: 2020] [added: 2021] | | |

| Electric utility | | | [removed: $3,421] [added: $3,345] | | | | | | [removed: $3,081] [added: $3,421] | | | | | | [removed: $2,920] [added: $3,081] | | |

| Gas utility | | | [removed: 642] [added: 540] | | | | | | [removed: 456] [added: 642] | | | | | | [removed: 373] [added: 456] | | |

| Other utility | | | [removed: 49] [added: 52] | | | | | | 49 | | | | | | 49 | | |

| Non-utility | | | [removed: 93] [added: 90] | | | | | | [removed: 83] [added: 93] | | | | | | [removed: 74] [added: 83] | | |

| Total revenues | | | [removed: 4,205] [added: 4,027] | | | | | | [removed: 3,669] [added: 4,205] | | | | | | [removed: 3,416] [added: 3,669] | | |

| Electric production fuel and purchased power | | | [removed: 830] [added: 736] | | | | | | [removed: 642] [added: 830] | | | | | | [removed: 652] [added: 642] | | |

| Electric transmission service | | | [removed: 573] [added: 583] | | | | | | [removed: 537] [added: 573] | | | | | | [removed: 449] [added: 537] | | |

| Cost of gas sold | | | [removed: 389] [added: 299] | | | | | | [removed: 258] [added: 389] | | | | | | [removed: 182] [added: 258] | | |

| Other operation and maintenance | | | [removed: 704] [added: 675] | | | | | | [removed: 676] [added: 704] | | | | | | [removed: 670] [added: 676] | | |

| Depreciation and amortization | | | [removed: 671] [added: 676] | | | | | | [removed: 657] [added: 671] | | | | | | [removed: 615] [added: 657] | | |

| Taxes other than income taxes | | | [removed: 110] [added: 115] | | | | | | [removed: 104] [added: 110] | | | | | | [removed: 108] [added: 104] | | |

| Total operating expenses | | | [removed: 3,277] [added: 3,084] | | | | | | [removed: 2,874] [added: 3,277] | | | | | | [removed: 2,676] [added: 2,874] | | |

| Operating income | | | [removed: 928] [added: 943] | | | | | | [removed: 795] [added: 928] | | | | | | [removed: 740] [added: 795] | | |

| Interest expense | | | [removed: 325] [added: 394] | | | | | | [removed: 277] [added: 325] | | | | | | [removed: 275] [added: 277] | | |

| Equity income from unconsolidated investments, net | | | [removed: (51)] [added: (61)] | | | | | | [removed: (62)] [added: (51)] | | | | | | [removed: (61)] [added: (62)] | | |

| Allowance for funds used during construction | | | [removed: (60)] [added: (21)] | | | | | | [removed: (25)] [added: (11)] | | | | | | [removed: (55)] [added: (9)] | | |

| Other | | | [removed: 6] [added: 3] | | | | | | [removed: 5] [added: 6] | | | | | | [removed: 14] [added: 5] | | |

| Total other (income) and deductions | | | [removed: 220] [added: 236] | | | | | | [removed: 195] [added: 220] | | | | | | [removed: 173] [added: 195] | | |

| Income before income taxes | | | [removed: 708] [added: 707] | | | | | | [removed: 600] [added: 708] | | | | | | [removed: 567] [added: 600] | | |

| Income tax expense (benefit) | | | [removed: 22] [added: 4] | | | | | | [removed: (74)] [added: 22] | | | | | | [removed: (57)] [added: (74)] | | |

| Net income | | | [removed: 686] [added: 703] | | | | | | [removed: 674] [added: 686] | | | | | | [removed: 624] [added: 674] | | |

| Preferred dividend requirements of Interstate Power and Light Company | | | — | | | | | | [removed: 15] [added: —] | | | | | | [removed: 10] [added: 15] | | |

[Table of C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)

February 16, 2024

[Table of C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)

[Table of C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)

| | | | 2023 | | | | | | 2022 | | |

| Accumulated other comprehensive income | | | 1 | | | | | | — | | |

[Table of C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)

| Depreciation and amortization | | | 676 | | | | | | 671 | | | | | | 657 | | |

| Materials and supplies | | | (62) | | | | | | (27) | | | | | | (13) | | |

| Proceeds from sales of partial ownership interests in West Riverside | | | 120 | | | | | | — | | | | | | — | | |

(a) 2023 includes $98 million of proceeds from renewable tax credits transferred to other corporate taxpayers

[Table of C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)

| At-the-market offering program, net and Shareowner Direct Plan issuances | | | | | | | | | 246 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 246 | | |

| Ending balance | | | $3 | | | | | | $3,030 | | | | | | $3,756 | | | | | | $1 | | | | | | ($13) | | | | | | $— | | | | | | | | | | | | $6,777 | | |

[Table of C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)

In our opinion, the financial statements present fairly, in all material respects, the financial position of the Company as of December 31, 2023 and 2022, and the results of its operations and its cash flows for each of the three years in the period ended December 31, 2023, in conformity with accounting principles generally accepted in the United States of America.

Regulatory Accounting - Impact of rate regulation on the financial statements - Refer to Notes 1, 2, and 3 to the financial statements

A change in these rulings may result in a material impact on results of operations and the amount of certain assets and liabilities in the financial statements.

Future regulatory rulings may impact the carrying value and accounting treatment of certain regulatory assets and regulatory liabilities.

[Table of C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)

We identified the impact of rate regulation as a critical audit matter due to the significant judgments made by management to support its assertions about certain impacted account balances and disclosures and the high degree of subjectivity involved in assessing the impact of relevant future regulatory orders on the financial statements.

- We tested the effectiveness of management’s controls over the evaluation of certain regulatory assets and regulatory liabilities, including the monitoring and evaluation of regulatory developments that may affect the likelihood of recovering costs in future rates or of a future reduction in rates.

- We inspected and evaluated the Company’s analysis supporting the probability of recovery for certain regulatory assets or refund to customers or future reduction in customer rates for regulatory liabilities not yet addressed in a regulatory order to assess management’s assertions.

- We inquired of management regarding current events impacting the Company and inspected minutes of the board of directors and other committees of the Company and evaluated whether matters were identified that may have an impact on certain recorded regulatory assets and liabilities.

- We read relevant regulatory orders, interpretations, filings made by the Company or its stakeholders, and other publicly available information issued by the regulatory agencies that pertain to the Company.

We evaluated the external information and assessed whether there are matters in such information that would be contradictory to management’s assertion of probability of recovery of certain regulatory assets or refund of regulatory liabilities.

- We evaluated the Company’s disclosures related to the impacts of rate regulation and regulatory developments, including disclosures related to certain regulatory balances recorded.

February 16, 2024

[Table of C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)

[Table of C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)

| | | | 2023 | | | | | | 2022 | | |

| Other | | | 101 | | | | | | 141 | | |

[Table of C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)

| Depreciation and amortization | | | 388 | | | | | | 381 | | | | | | 375 | | |

| Materials and supplies | | | (39) | | | | | | (13) | | | | | | (7) | | |

| Cash receipts on sold receivables | | | 453 | | | | | | 598 | | | | | | 502 | | |

| Beneficial interest obtained in exchange for securitized accounts receivable | | | $216 | | | | | | $185 | | | | | | $214 | | |

(a) 2023 includes $76 million of proceeds from renewable tax credits transferred to other corporate taxpayers

[Table of C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)

| 2023: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |

| | | | | | | | | |

| --- | --- | --- | --- | --- | --- | --- | --- | --- |

| | | | 41 | | | | | |

As of December 31, 2022, the Company had a recorded consolidated regulatory assets balance of $2,046 million and regulatory liabilities balance of $1,324 million.

| | | | 42 | | | | | |

- We inquired of management about property, plant, and equipment, net that may be abandoned.

| | | | 43 | | | | | |

| | | | | | | | | | | | |

| Contributions from noncontrolling interest | | | 29 | | | | | | — | | | | | | — | | |

| 2020: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |

| Beginning balance | | | $2 | | | | | | $2,446 | | | | | | $2,766 | | | | | | $1 | | | | | | ($10) | | | | | | $200 | | | | | | $— | | | | | | $5,405 | | |

| Adoption of new accounting standard, net of tax (refer to [Note 1(](#i1fc9d0e18c654199a6dadea9bc41997a_238)[l](#i1fc9d0e18c654199a6dadea9bc41997a_238)[)](#i1fc9d0e18c654199a6dadea9bc41997a_238)) | | | | | | | | | | | | | | | (9) | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | (9) | | |

| Shareowner Direct Plan issuances | | | | | | | | | 25 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 25 | | |

| Contributions from noncontrolling interest | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 29 | | | | | | 29 | | |

| Distributions to noncontrolling interest | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | (29) | | | | | | (29) | | |

As of December 31, 2022, the Company had a recorded consolidated regulatory assets balance of $1,386 million and regulatory liabilities balance of $754 million.

| Other | | | 4 | | | | | | (10) | | | | | | (20) | | |

| 2020: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |

| Ending balance | | | 33 | | | | | | 2,752 | | | | | | 979 | | | | | | 200 | | | | | | 3,964 | | |

As of December 31, 2022, the Company had a recorded consolidated regulatory assets balance of $660 million and regulatory liabilities balance of $570 million.

| Other | | | 3 | | | | | | 3 | | | | | | 5 | | |

| Other | | | (1) | | | | | | 2 | | | | | | 3 | | |

| Gas stored underground, at weighted average cost | | | 73 | | | | | | 42 | | |

| Other | | | 60 | | | | | | 86 | | |

| Commercial paper | | | 290 | | | | | | 236 | | |

| Other | | | 111 | | | | | | 112 | | |

| Deferred tax expense (benefit) and tax credits | | | 4 | | | | | | (79) | | | | | | (15) | | |

| Other | | | (15) | | | | | | 11 | | | | | | 2 | | |

| Other | | | (47) | | | | | | (44) | | | | | | 6 | | |

| Other | | | (13) | | | | | | (30) | | | | | | (7) | | |

| Payments to retire long-term debt | | | (250) | | | | | | — | | | | | | (150) | | |

| Other | | | (9) | | | | | | (12) | | | | | | (8) | | |

| | | | Total WPL Common Equity | | | | | | | | | | | | | | | | | | | | | | | | | | |

| Beginning balance | | | $66 | | | | | | $1,434 | | | | | | $864 | | | | | | $— | | | | | | $2,364 | | |

| Ending balance | | | 66 | | | | | | 1,459 | | | | | | 953 | | | | | | — | | | | | | 2,478 | | |

| Contributions from noncontrolling interest | | | | | | | | | | | | | | | | | | | | | 29 | | | | | | 29 | | |

| Distributions to noncontrolling interest | | | | | | | | | | | | | | | | | | | | | (29) | | | | | | (29) | | |

| Other | | | | | | | | | (1) | | | | | | | | | | | | | | | | | | (1) | | |

Federal Tax Reform repealed corporate federal alternative minimum tax and allowed unutilized alternative minimum tax credits to be refunded over four tax years beginning with the U.S. federal tax return for calendar year 2018.

Pursuant to the Coronavirus Aid, Relief, and Economic Security Act, Alliant Energy received the remaining alternative minimum tax credits refunds in 2020.

| | | | | | | | | |

| --- | --- | --- | --- | --- | --- | --- | --- | --- |

| | | | 99 | | | | | |

[Table of C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)

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 of the end of the quarter ended December 31, [removed: 2022] [added: 2023] pursuant to the requirements of the Securities Exchange Act of 1934, as amended.

Based on their evaluation, the Chief Executive Officer and the Chief Financial Officer concluded that Alliant Energy’s, IPL’s and WPL’s disclosure controls and procedures were effective as of the end of the quarter ended December 31, [removed: 2022.][added: 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 December 31, [removed: 2022] [added: 2023] that has materially affected, or is reasonably likely to materially affect, Alliant Energy’s, IPL’s and WPL’s internal control over financial reporting.

Alliant Energy’s, IPL’s and WPL’s management assessed the effectiveness of their respective internal control over financial reporting as of December 31, [removed: 2022] [added: 2023] using the criteria set forth in *Internal Control - Integrated Framework (2013)* issued by the Committee of Sponsoring Organizations of the Treadway Commission.

Based on these assessments, Alliant Energy’s, IPL’s and WPL’s management concluded that, as of December 31, [removed: 2022,] [added: 2023,] their respective internal control over financial reporting was effective.

[Table of [removed: Co](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)][added: C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)]

We have audited the internal control over financial reporting of Alliant Energy Corporation and subsidiaries (the “Company”) as of December 31, [removed: 2022,] [added: 2023,] based on criteria established in *Internal Control - Integrated Framework (2013)* issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO).

In our opinion, the Company maintained, in all material respects, effective internal control over financial reporting as of December 31, [removed: 2022,] [added: 2023,] based on criteria established in *Internal Control - Integrated Framework (2013)* issued by COSO.

We have also audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the consolidated financial statements as of and for the year ended December 31, [removed: 2022,] [added: 2023,] of the Company and our report dated February [removed: 24, 2023,] [added: 16, 2024,] expressed an unqualified opinion on [removed: those] [added: the Company’s 2023] financial statements.

| | | | 100 | | | | | |

February 16, 2024

| | | | 101 | | | | | |

[Table of C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)

| | | | 97 | | | | | |

February 24, 2023

| | | | 98 | | | | | |

During the quarter ended December 31, 2023, no director or officer of Alliant Energy, IPL or WPL adopted or terminated a Rule 10b5-1 trading arrangement or non-Rule 10b5-1 trading arrangement, as each term is defined in Item 408(a) of Regulation S-K.

None.

The information required by Item 10 relating to directors and nominees for election of directors at the [removed: 2023] [added: 2024] Annual Meeting of Shareowners, the timely filing of reports under Section 16 of the Securities Exchange Act of 1934, audit committees and audit committee financial experts, and Alliant Energy’s, IPL’s and WPL’s Code of Conduct is incorporated herein by reference to the relevant information in the [removed: 2023] [added: 2024] Alliant Energy Proxy Statement, which will be filed with the SEC within 120 days after the end of Alliant Energy’s, IPL’s and WPL’s fiscal years.

Therefore, the information required by Item 11 for each of Alliant Energy, IPL and WPL is incorporated herein by reference to the relevant information in the [removed: 2023] [added: 2024] Alliant Energy Proxy Statement, which will be filed with the SEC within 120 days after the end of Alliant Energy’s, IPL’s and WPL’s fiscal years.

Information regarding Alliant Energy’s equity compensation plans as of December 31, [removed: 2022] [added: 2023] was as follows:

As of December 31, [removed: 2022,] [added: 2023,] there were performance shares and restricted stock units (performance- and time-vesting) outstanding under the 2020 OIP, the only plan under which such equity awards are currently granted.

(c)As of December 31, [removed: 2022,] [added: 2023,] there were [removed: 402,134] [added: 379,006] shares of Alliant Energy’s common stock held under the DCP, which is described in [Note 13(c)](#i1fc9d0e18c654199a6dadea9bc41997a_310).

The remainder of the information required by Item 12 for Alliant Energy, and the information required by Item 12 for each of IPL and WPL, is incorporated herein by reference to the relevant information in the [removed: 2023] [added: 2024] Alliant Energy Proxy Statement, which will be filed with the SEC within 120 days after the end of Alliant Energy’s, IPL’s and WPL’s fiscal year.

[Table of [removed: Co](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)][added: C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)]

| Equity compensation plans approved by shareowners | | | | | | 1,217,445 (a) | | | | | | $52.66 | | | | | | 7,714,741 (b) | | |

| | | | | | | 1,217,445 | | | | | | $52.66 | | | | | | 7,714,741 | | |

| | | | 102 | | | | | |

| Equity compensation plans approved by shareowners | | | | | | 713,876 (a) | | | | | | $51.92 | | | | | | 8,259,869 (b) | | |

| | | | | | | 713,876 | | | | | | $51.92 | | | | | | 8,259,869 | | |

| | | | 99 | | | | | |

The information required by Item 13 for each of Alliant Energy, IPL and WPL is incorporated herein by reference to the relevant information in the [removed: 2023] [added: 2024] Alliant Energy Proxy Statement, which will be filed with the SEC within 120 days after the end of Alliant Energy’s, IPL’s and WPL’s fiscal years.

The information required by Item 14 is incorporated herein by reference to the relevant information in the [removed: 2023] [added: 2024] Alliant Energy Proxy Statement, which will be filed with the SEC within 120 days after the end of Alliant Energy’s fiscal year.

| Audit fees | | | [removed: $1,351] [added: $1,468] | | | | | | 95% | | | | | | [removed: $1,367] [added: $1,351] | | | | | | [removed: 96%] [added: 95%] | | | | | | [removed: $1,096] [added: $1,228] | | | | | | [removed: 91%] [added: 92%] | | | | | | [removed: $1,005] [added: $1,096] | | | | | | [removed: 90%] [added: 91%] | | |

| Audit-related fees | | | [removed: 56] [added: 57] | | | | | | 4% | | | | | | [removed: 49] [added: 56] | | | | | | 4% | | | | | | [removed: 94] [added: 103] | | | | | | 8% | | | | | | [removed: 85] [added: 94] | | | | | | 8% | | |

| Tax fees | | | [removed: 10] [added: 8] | | | | | | 1% | | | | | | [removed: 3] [added: 10] | | | | | | [removed: —%] [added: 1%] | | | | | | [removed: 8] [added: 7] | | | | | | [removed: 1%] [added: —%] | | | | | | [removed: 18] [added: 8] | | | | | | [removed: 2%] [added: 1%] | | |

| All other fees | | | [removed: 7] [added: 4] | | | | | | —% | | | | | | [removed: 4] [added: 7] | | | | | | —% | | | | | | [removed: 5] [added: 4] | | | | | | —% | | | | | | [removed: 3] [added: 5] | | | | | | —% | | |

| | | | [removed: $1,424] [added: $1,537] | | | | | | 100% | | | | | | [removed: $1,423] [added: $1,424] | | | | | | 100% | | | | | | [removed: $1,203] [added: $1,342] | | | | | | 100% | | | | | | [removed: $1,111] [added: $1,203] | | | | | | 100% | | |

IPL’s and WPL’s audit fees for [removed: 2022] [added: 2023] and [removed: 2021] [added: 2022] consisted of the respective fees billed for the audits of the financial statements of IPL and its subsidiaries and WPL and its subsidiaries, for reviews of financial statements included in Form 10-Q filings, and for services normally provided in connection with statutory and regulatory filings, such as financing transactions.

IPL’s and WPL’s audit fees also included their respective portion of fees for the [removed: 2022] [added: 2023] and [removed: 2021] [added: 2022] audits of Alliant Energy’s financial statements and effectiveness of internal controls over financial reporting.

IPL’s and WPL’s audit-related fees for [removed: 2022] [added: 2023] and [removed: 2021] [added: 2022] consisted of the fees billed for services rendered related to employee benefits plan audits and other attest services.

IPL’s and WPL’s tax fees for [removed: 2022] [added: 2023] and [removed: 2021] [added: 2022] consisted of the fees billed for professional services rendered for tax compliance, tax advice and tax planning, including all services performed by the tax professional staff of affiliates of the independent registered public accounting firm, except those rendered in connection with the audit.

All other fees for [removed: 2022] [added: 2023] and [removed: 2021] [added: 2022] for IPL and WPL consisted of license fees for accounting research software products and [removed: virtual] seminars.

[Table of [removed: Co](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)][added: C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)]

| | | | 2023 | | | | | | | | | | | | 2022 | | | | | | | | | | | | 2023 | | | | | | | | | | | | 2022 | | | | | | | | |

| | | | 103 | | | | | |

| | | | 2022 | | | | | | | | | | | | 2021 | | | | | | | | | | | | 2022 | | | | | | | | | | | | 2021 | | | | | | | | |

| | | | 100 | | | | | |

| CONDENSED STATEMENTS OF INCOME | | | [removed: 2022] [added: 2023] | | | | | | [removed: 2021] [added: 2022] | | | | | | [removed: 2020] [added: 2021] | | |

| Operating expenses | | | [removed: $9] [added: $3] | | | | | | [removed: $5] [added: $9] | | | | | | [removed: $7] [added: $5] | | |

| Operating loss | | | [removed: (9)] [added: (3)] | | | | | | [removed: (5)] [added: (9)] | | | | | | [removed: (7)] [added: (5)] | | |

| Equity earnings from consolidated subsidiaries | | | [removed: (707)] [added: (742)] | | | | | | [removed: (664)] [added: (707)] | | | | | | [removed: (625)] [added: (664)] | | |

| Interest expense | | | [removed: 6] [added: 34] | | | | | | [removed: 1] [added: 6] | | | | | | [removed: 2] [added: 1] | | |

| Other | | | [removed: 1] [added: 4] | | | | | | 1 | | | | | | [removed: 4] [added: 1] | | |

| Total other (income) and deductions | | | [removed: (700)] [added: (704)] | | | | | | [removed: (662)] [added: (700)] | | | | | | [removed: (619)] [added: (662)] | | |

| Income before income taxes | | | [removed: 691] [added: 701] | | | | | | [removed: 657] [added: 691] | | | | | | [removed: 612] [added: 657] | | |

| Income tax expense (benefit) | | | [removed: 2] [added: (5)] | | | | | | [removed: (5)] [added: 2] | | | | | | [removed: (4)] [added: (5)] | | |

| Net income | | | [removed: $689] [added: $706] | | | | | | [removed: $662] [added: $689] | | | | | | [removed: $616] [added: $662] | | |

| CONDENSED BALANCE SHEETS | | | [removed: 2022] [added: 2023] | | | | | | [removed: 2021] [added: 2022] | | |

| Notes receivable from affiliated companies | | | [removed: $65] [added: $96] | | | | | | [removed: $16] [added: $65] | | |

| Other | | | 1 | | | | | | [removed: 5] [added: 1] | | |

| Total current assets | | | [removed: 66] [added: 97] | | | | | | [removed: 21] [added: 66] | | |

| Investments in consolidated subsidiaries | | | [removed: 7,801] [added: 8,405] | | | | | | [removed: 7,061] [added: 7,801] | | |

| Total investments | | | [removed: 7,803] [added: 8,407] | | | | | | [removed: 7,063] [added: 7,803] | | |

| Other assets | | | [removed: 97] [added: 90] | | | | | | [removed: 96] [added: 97] | | |

| Total assets | | | [removed: $7,966] [added: $8,594] | | | | | | [removed: $7,180] [added: $7,966] | | |

| Commercial paper | | | [removed: $352] [added: $157] | | | | | | [removed: $279] [added: $352] | | |

| Notes payable to affiliated companies | | | [removed: 1,318] [added: 1,068] | | | | | | [removed: 900] [added: 1,318] | | |

| Other | | | 10 | | | | | | [removed: 4] [added: 10] | | |

| Total current liabilities | | | [removed: 1,680] [added: 1,235] | | | | | | [removed: 1,183] [added: 1,680] | | |

| Other liabilities | | | [removed: 1] [added: 2] | | | | | | [removed: 2] [added: 1] | | |

| Common stock and additional paid-in capital | | | [removed: 2,780] [added: 3,033] | | | | | | [removed: 2,752] [added: 2,780] | | |

| Retained earnings | | | [removed: 3,518] [added: 3,768] | | | | | | [removed: 3,255] [added: 3,518] | | |

| Shares in deferred compensation trust | | | (13) | | | | | | [removed: (12)] [added: (13)] | | |

| Total common equity | | | [removed: 6,285] [added: 6,789] | | | | | | [removed: 5,995] [added: 6,285] | | |

| Total liabilities and equity | | | [removed: $7,966] [added: $8,594] | | | | | | [removed: $7,180] [added: $7,966] | | |

[Table of [removed: Co](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)][added: C](#i1fc9d0e18c654199a6dadea9bc41997a_7)[o](#i1fc9d0e18c654199a6dadea9bc41997a_7)[ntents](#i1fc9d0e18c654199a6dadea9bc41997a_7)]

| CONDENSED STATEMENTS OF CASH FLOWS | | | [removed: 2022] [added: 2023] | | | | | | [removed: 2021] [added: 2022] | | | | | | [removed: 2020] [added: 2021] | | |

| Net cash flows from operating activities | | | [removed: $492] [added: $445] | | | | | | [removed: $494] [added: $492] | | | | | | [removed: $396] [added: $494] | | |

| Capital contributions to consolidated subsidiaries | | | [removed: (530)] [added: (325)] | | | | | | [removed: (295)] [added: (530)] | | | | | | [removed: (429)] [added: (295)] | | |

| Net change in notes receivable from and payable to affiliates | | | [removed: 369] [added: (281)] | | | | | | [removed: (21)] [added: 369] | | | | | | [removed: 201] [added: (21)] | | |

| Dividends from consolidated subsidiaries in excess of equity earnings | | | — | | | | | | [removed: 50] [added: —] | | | | | | [removed: —] [added: 50] | | |