What changed in this filing

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Item 1A. Risk Factors

2026-02-20 compared with 2025-02-21 · 46 added, 36 removed, 213 unchanged (28% of the section changed)

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If any of the following risks develop into actual events, our business, financial condition or results of operations could be materially and adversely affected, and you may lose all or part of your investment.

Risks Related to Data Center and Other Large Load Growth Customers

Demand from data centers and other large load growth customers may impact our business - Our ability to manage the development and implementation of complex business opportunities related to the growing demand for data centers may be limited by financial, operational, or regulatory factors.

We may enter into agreements requiring significant capital investment in generation and transmission capacity for large load growth customers before realizing any potential returns.

We may not be able to affordably and timely construct generation, or cause transmission companies to affordably and timely construct transmission infrastructure to meet potential load growth from any large load growth customer.

A large load growth customer may decide not to take energy, take less energy than anticipated, or not take service on the anticipated schedule, due to changes in business needs, construction delays, technological advances that improve energy efficiency, or other factors, which may result in lower demand for energy than anticipated.

The addition of large load growth customers may increase the concentration of sales, and increase revenue and earnings volatility.

We may not be able to adequately protect against the risks inherent in relying on rapid growth within a small number of large customers in a single industry.

The inability or delays in obtaining regulatory approvals with acceptable conditions or providing sufficient generation or securing transmission, due to supply chain risk, operational risk, or other factors, may impact our ability, or the cost, to provide energy to new customers.

The individual customer rates may not provide sufficient revenues to fully recover the costs, the contracts with large load growth customers may increase counterparty credit risk, and the costs to provide service may be higher than expected.

Large load growth customers may not be able to meet obligations in our contracts, including the obligation to pay any termination charges.

Additionally, if pipeline expansions needed for new gas‑fired generation are delayed or not approved, we may be unable to meet peak requirements for data center load, increasing market purchases or capacity procurement costs.

Any of these circumstances could adversely affect our business, financial condition, results of operations and growth prospects.

Laws, regulations, and opposition to data centers may impact our business - Federal, state or local legislation, rulemaking, or siting standards that specifically restrict or delay the zoning, siting or operation of data centers could reduce or defer expected load growth and impair cost recovery for associated infrastructure.

Community opposition to data centers—driven by concerns about land use, water consumption, generation emissions, noise, or traffic—could result in permitting delays, litigation, project cancellations, or additional mitigation costs, reducing expected load growth.

The ability to serve significant new commercial or industrial customers on contract rates, including data centers, may require certain regulatory approvals, and the activities and costs related to the construction, acquisition or contracts for additional generation capacity and transmission required to meet the high demands of such customers could be significant.

The individual customer rates for large load growth customers are subject to regulatory approvals and our regulatory authorities may change the rates we can charge and the costs that can be recovered.

As a result, we may experience adverse impacts on our financial condition and results of operations.

Risks Related to Laws and Regulations

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Our ability to timely obtain rate adjustments to earn authorized rates of return depends upon timely regulatory action under applicable statutes and regulations, and cannot be guaranteed.

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, earnings above certain thresholds may be required to be refunded, recovery of capital expenditures, including those for electric distribution systems, above certain thresholds may be capped or not be allowed, rates may be temporarily frozen, such as IPL’s current retail electric rate base moratorium through September 2029, laws, rules or settlements 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.

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, earnings above certain thresholds may be required to be refunded or be used to reduce existing rate base of assets with higher levels of authorized return on equity, recovery of capital expenditures, including those for electric distribution systems, above certain thresholds may be capped or not be allowed, rates may be temporarily frozen, such as IPL’s current retail electric rate base moratorium through September 2029, laws, rules or settlements 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.

As a result, we may experience adverse impacts on our financial condition and results of operations.

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The impacts on our operations include:

our ability to site and construct new energy facilities, such as renewable energy, energy storage projects, or natural gas-fired electric generating units, and recover associated costs;

our ability to decommission generating facilities

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and recover related costs and the remaining carrying value of these facilities and related assets;

our ability to site and construct new energy facilities, such as renewable energy, energy storage projects, or natural gas-fired electric generating units (EGUs), and recover associated costs;

our ability to decommission generating facilities and recover related costs and the remaining carrying value of these facilities and related assets;

MISO’s resource adequacy process establishing seasonal capacity planning reserve margin and capacity accreditation requirements, as well as additional changes to capacity accreditation, such as the direct loss of load methodology, impact how and when existing and new generating facilities such as IPL’s and WPL’s additional solar generation are 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 seasonal resource adequacy process, or procure capacity 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 seasonal resource adequacy process;

legislation or regulation that imposes mandatory integrated resource planning requirements, or materially changes existing resource planning standards, could delay approvals, require revisions to resource plans, increase compliance costs, and impact our ability to timely meet demand for energy from commercial and industrial customers, including data centers;

the impact of the lack of availability of existing and new generating facilities on our accredited capacity for such facilities pursuant to MISO’s seasonal resource adequacy process;

IPL’s ability to achieve certain aggregate summer capacity factors under the consumer protection plan for its up to 400 MW of solar generation projects;

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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 projects, or to record an impairment of our 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.

Our regulators or legislatures could change regulations or laws to permit third parties to provide renewable energy directly to our customers without being treated as a utility, potentially causing a competitive disadvantage for us.

Legislative or regulatory changes that enable large load growth customers, including data centers, to own or procure on-site generation or to self-supply through sources behind-the-meter or behind-the-meter arrangements could materially reduce retail sales, shift cost recovery to remaining customers, and impact our ability to earn authorized rates of return.

Changes to these regulations could materially increase our costs or cause us to reconsider our strategy, which could have a material adverse impact on our financial condition and results of operations.

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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 or future Presidential or Gubernatorial Administrations.

These laws and regulations have imposed, and proposed laws and regulations could impose in the future, additional costs on our utility operations and requirements that impact our ability to continue operating electric generating units.

We have incurred, and will continue to incur, capital and other expenditures to comply with these and other environmental laws and regulations.

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The pace and feasibility to fully achieve decarbonization is also contingent on the future development and full-scale deployment of emerging energy technologies and supporting infrastructure, as well as electrification of other economic sectors.

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Changing economic conditions and drivers to support significant load growth, including data centers, could influence electric demand.

This could affect the timing of retirement for our existing coal-fired electric generating units, and our need to add new fossil-fueled generation resources due to growing electric loads.

This could affect the timing of retirement for our existing coal-fired EGUs, and our need to add new fossil-fueled generation resources due to growing electric loads.

We may not be able to meet our resource adequacy requirements if GHG regulations require us to shut down fossil fuel generating facilities before we can build new generating facilities to meet growing demand for electricity.

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 U.S.

Environmental Protection Agency’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.

Environmental Protection Agency’s proposed rules to regulate GHG emissions at fossil-fuel fired EGUs 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.

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Potential future requirements to reduce GHGs from the energy and manufacturing sectors could affect our operations in various ways.

Regulation or legislation mandating GHG emissions reductions or other clean energy standards affecting utility companies could materially increase costs, causing some electric generating units to be uneconomical to operate or maintain.

We are vulnerable to potential risks associated with the construction of electric generating units that may extend to our supply chain and natural gas operations.

Regulation or legislation mandating GHG emissions reductions or other clean energy standards affecting utility companies could materially increase costs, causing some EGUs to be uneconomical to operate or maintain.

We are vulnerable to potential risks associated with the construction of EGUs that may extend to our supply chain and natural gas operations.

Regulation of oil and gas production could affect our upstream supply of natural gas for electricity generation and to provide directly to our residential and business customers from our local distribution company.

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We have sold, and continue to plan to sell, a substantial amount of our eligible renewable tax credits.

However, the One Big Beautiful Bill Act (OBBB Act) includes significant changes to renewable tax credits, including accelerating the termination of production tax credits and investment tax credits.

These changes may materially limit our ability to sell or transfer renewable tax credits at reasonable terms in future periods.

The inability to sell renewable tax credits at reasonable terms, or the determination that renewable tax credits that we generate or sell are not eligible or are eligible at a different rate, could materially impact our tax credit carryforward position or result in liability to purchasers of the tax credits, which could subject us to significant litigation, liability and costs.

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In addition, our tax liability is determined by our taxable income multiplied by the current tax rates in effect.

If the federal or state tax rates are increased, or we become subject to a corporate alternative minimum tax, we may experience adverse impacts to our financial condition and results of operations until those rates are reflected in our regulatory filings.

If the federal or state tax rates are increased, state income tax apportionment is increased, or we become subject to a corporate alternative minimum tax, we may experience adverse impacts to our financial condition and results of 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 that are eligible to be used to reduce our federal tax obligations.

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A variety of operating and economic parameters, including transmission constraints, the imbalance of supply and demand of energy resulting in unfavorable pricing for wind or solar energy, adverse weather conditions and breakdown or failure of equipment, could significantly reduce the production tax credits generated by our wind or solar facilities resulting in a material adverse impact on our financial condition and results of operations.

The OBBB Act’s early termination of production tax credits for projects beginning construction more than 12 months after enactment may also limit our ability to qualify new facilities for future production tax credits.

Our utility business is developing energy storage facilities, which are expected to generate investment tax credits.

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If there is a disagreement on the qualifying costs or whether the 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.

If energy storage facilities are not completed in the anticipated timeframe or investment tax credits are not able to be generated or sold due to the repeal or amendment of the Inflation Reduction Act of 2022, we may experience adverse impacts on our financial condition and results of operations.

If energy storage facilities are not completed in the anticipated timeframe or investment tax credits are not able to be generated or sold due to the repeal or amendment of the Inflation Reduction Act of 2022, or new limitations imposed by the OBBB Act, we may experience adverse impacts on our financial condition and results of operations.

The Inflation Reduction Act 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 renewable projects 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.

The Inflation Reduction Act and related guidance also include limitations on the use of components and/or financing from entities with ties to certain foreign countries.

If our generation or energy storage projects include equipment or subcomponents sourced from entities with ties to certain foreign countries, related production or investment tax credits may be reduced or denied, which could increase customer costs and adversely affect our financial condition.

The OBBB Act further expands limitations on the use of components and/or financing from entities with ties to certain foreign countries, which could reduce or disqualify renewable tax credits for generation and energy storage projects.

Risks Related to Business Operations

Demand for energy may decrease - Our results of operations are affected by the demand for energy in our service territories.

Energy demand may decrease due to many things, including economic conditions, proliferation of customer and third party-

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owned generation, technological advances that reduce the costs of renewable energy and energy storage solutions for our customers, government policies, such as the Inflation Reduction Act of 2022, which incentivize customer and third party-owned generation, loss of service territory or franchises, energy efficiency measures, changes in customer usage due to rate design changes, such as time of use rates, technological advances that improve energy efficiency, third-party disrupters, loss of wholesale customers, loss of customers that pursue their own renewable projects to achieve specific sustainability goals, and the adverse impact of tariffs on our customers.

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

We may not realize anticipated or expected growth from large load growth customers, due to many factors, including changes in customers’ goals, changes in environmental policies, improvements in energy efficiency or technology, or competition from other companies.

The loss of sales due to lower demand for energy may increase our rates for remaining customers, as our rates must cover our fixed costs.

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Thus, mild winters and/or summers could have an adverse impact on our financial condition and results of operations.

Demand for energy from high usage customers may impact our business - The ability to serve significant new commercial or industrial customers on contract rates, including data centers, may require certain regulatory approvals, and the activities and costs related to the construction, acquisition or contracts for additional generation capacity and transmission required to meet the high demands of such customers could be significant.

The inability or delays in obtaining regulatory approvals or securing additional capacity or transmission, due to supply chain risk, operational risk, or other factors, may impact our ability, or the cost, to provide energy to new customers, the contract rates may not fully recover the costs, the contracts may increase counterparty credit risk, and the costs to provide service may be higher than expected.

The contract rates for high usage customers are subject to regulatory approvals and our regulatory authorities may change the rates we can charge and the costs that can be recovered.

A high usage customer may decide not to take energy, take less energy than anticipated, or not take service on the anticipated schedule, due to changes in business needs, construction delays, technological advances that improve energy efficiency, or other factors, which may result in lower demand for energy than anticipated.

The addition of high usage customers may increase the concentration of sales, and increase revenue and earnings volatility.

These factors could negatively impact our financial condition and results of operations.

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 information and telecommunications systems.

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These risks include:

the inability to obtain necessary regulatory approvals and permits in a timely

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the inability to obtain necessary regulatory approvals and permits in a timely manner;

adverse interpretation or enforcement of permit conditions;

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We may not be able to recover all costs for the projects in rates and face increased risk of potential impairment of our project investment if a construction project is not completed or is delayed, or final costs exceed expectations or the costs approved by our regulators.

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

We may not be able to meet capacity requirements, including new demand from high usage customers, to comply with electric demand planning reserve margins if a construction project is not completed or is delayed.

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

We may not be able to provide sufficient transmission capacity in a timely manner or transmission providers may be unable to timely provide transmission upgrades to enable connecting new generation to the grid, which could delay expected system load demand from large load growth customers such as data centers, expose us to market purchases and reduce expected revenues.

These risks could cause significant harm to employees, customers and the public, including loss of human life, significant damage to property, adverse impacts on the environment and impairment of our operations, all of which could result in substantial financial losses to us.

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Any losses for which we are not fully insured or that are not covered by insurance at all could materially adversely affect our results of operations and financial position.

Storms and natural disasters may impact our customers and the resulting reduced demand for energy could cause

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lower sales and revenues, which may not be replaced or recovered in rates, or rate recovery may be delayed.

Storms and natural disasters may impact our customers and the resulting reduced demand for energy could cause lower sales and revenues, which may not be replaced or recovered in rates, or rate recovery may be delayed.

Any of these items could adversely impact our financial condition and results of operations.

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Our counterparties to these contracts may not fulfill their obligations to provide natural gas, coal, financial settlements or 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 units 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, need to secure higher cost delivery of natural gas or coal, be forced to 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 MISO energy market and/or be required to purchase replacement capacity to comply with electric demand planning reserve margins.

If we were unable to obtain enough natural gas or coal for our EGUs 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, need to secure higher cost delivery of natural gas or coal, be forced to 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 MISO energy market and/or be required to purchase replacement capacity to comply with electric demand planning reserve margins.

We may be obligated to pay for coal deliveries under our contracts even if our coal-fired generating facilities do not operate enough to fully utilize the amounts of coal covered by the contracts.

If, for natural gas delivery to our customers, we were unable to obtain our natural gas supply requirements under existing or future natural gas supply and transportation contracts, we could be required to purchase natural gas at higher prices from other sources.

Natural gas market prices have been volatile in the past and could be volatile in the future due to additional future regulations, increased demand including due to increased liquified natural gas demand from foreign countries, limited global suppliers of natural gas, periods of extremely cold temperatures or disruption in supply caused by major storms or pipeline explosions.

Natural gas market prices have been volatile in the past and could be volatile in the future due to additional future regulations, increased demand including due to new natural gas-fired generating facilities, increased liquified natural gas demand from foreign countries, limited global suppliers of natural gas, periods of extremely cold temperatures or disruption in supply caused by major storms or pipeline explosions.

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

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We are also subject to collective bargaining agreements covering approximately 1,700 employees.

Any work stoppage experienced in connection with negotiations of

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collective bargaining agreements could adversely affect our financial condition and results of operations as well as our ability to implement our strategy.

Any work stoppage experienced in connection with negotiations of collective bargaining agreements could adversely affect our financial condition and results of operations as well as our ability to implement our strategy.

We are subject to limitations on our ability to pay dividends - Alliant Energy is a holding company with no significant operations of its own.

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IPL and WPL have entered into conditional commitments with the U.S.

Department of Energy’s Loan Programs Office for loan guarantees of approximately $3 billion in aggregate and WPL has been selected for additional grants.

Department of Energy Office of Energy Dominance Financing, formerly the Loan Programs Office, for loan guarantees of approximately $3 billion in aggregate and WPL has been selected for additional grants.

The inability to access these funds due to federal action or other reasons may increase our costs and interest rates.

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Compared sentence by sentence after normalising whitespace, quotation marks, case and digits, so re-formatting and restated figures do not read as changed language. Wording changes appear as one removal and one addition. The current filing and the prior one are authoritative.

What changed 10-K

Item 1A. Risk Factors