Otter Tail Corp

There have been no material changes from the risk factors disclosed in Item 1A, Risk Factors, of our Annual Report on Form 10-K for the year ended December 31, 2023, except for the risk factor below.

Legislation, regulation, litigation or other actions related to climate change and greenhouse gas emissions could materially impact us.

Current and future federal, state, regional and international regulations to address global climate change and reduce GHG emissions, including measures such as mandated levels of renewable generation, mandatory reductions in CO 2 emission levels, taxes on CO 2 emissions, or cap-and-trade regimes, could require us to incur significant costs which could negatively impact our financial condition, operating results and liquidity if such costs cannot be recovered through rates granted by rate-making authorities or through increased market prices for electricity.

In April 2024, the EPA finalized new regulations under Section 111 of the Clean Air Act to regulate GHG emissions from existing and new fossil fuel-based power plants. The new regulations require existing coal-fired power plants to achieve certain CO 2 emissions reduction levels, with the amount of reduction dependent upon the remaining operating life of the facility. The new regulation has the potential to materially impact the operations of our coal-fired power plants, which could have a material impact on our operating results, financial condition and liquidity.

In addition to complying with legislation and regulation, we could be subject to litigation related to climate change. If we were subjected to such litigation, the costs of such litigation could be significant and an adverse outcome could require substantial capital expenditures, changes in operations and possible payment of penalties or damages which could affect our financial condition, operating results and liquidity if the costs are not recoverable in rates or covered by insurance.