Ameren Missouri has updated its 2026 Integrated Resource Plan (IRP), outlining a 20-year strategy for maintaining reliable electric service and managing costs under different customer energy-use scenarios.

The plan considers projected customer energy needs, economic growth, available energy technologies and associated costs. 

"Our customers depend on us to make thoughtful decisions about the energy system that powers their homes, businesses and communities," said Martin J. Lyons Jr., chairman, president and chief executive officer of Ameren Corporation. "This plan provides a clear path for maintaining reliability, supporting the communities we serve by making the most of existing resources while prudently investing in a mix of additional generation technologies to cost-effectively power the future needs of our customers."

The IRP maintains a mix of existing and planned generation resources intended to support reliability under a range of future conditions. Ameren Missouri evaluated more than 20 potential resource plans before selecting its preferred portfolio, which includes new generation, battery storage and other investments.

The preferred plan includes the following resource additions:

• Combined-cycle natural gas generation: 2,100 megawatts (MW) scheduled to be in service by 2031, an additional 2,800 MW by 2035 and another 1,400 MW by 2042.

• Simple-cycle natural gas generation: 1,900 MW of on-demand capacity planned by 2029, with an additional 2,400 MW after 2040.

• Natural gas fuel cells: 500 MW planned by 2030. The plan identifies fuel cells as a scalable technology capable of providing on-demand electricity.

• Solar generation: 1,300 MW planned by 2030 and an additional 2,300 MW by 2045.

• Wind generation: 1,500 MW planned after 2030.

• Battery storage: 2,400 MW planned by 2030 to help make electricity available during periods of high demand.

• Nuclear generation: 1,200 MW planned by 2040. Ameren Missouri has not selected a location or technology but is considering advanced large-scale reactor designs and small modular reactors. The company also continues to expect to seek an extension to operate the Callaway Energy Center beyond 2044.

"Reliable service is built on a mix of energy resources that can be called upon under different conditions," said Aaron Melda, chairman and president of Ameren Missouri. "Because no single technology can meet every customer's energy needs on its own, the IRP evaluates how resources can work together to maintain reliability, adapt as customer energy use evolves, and manage costs over time."

The plan also accounts for Ameren Missouri's commitments to serve 2.8 gigawatts of aggregate large-load demand by 2030 through signed electric service agreements, with the potential for additional growth.

According to the company, state law and its Powering Missouri Growth Plan include provisions requiring large-load customers to cover the costs of the infrastructure needed to serve them. These provisions are intended to protect existing customers while supporting reliable service for all customers.

Ameren Missouri files its IRP with the Missouri Public Service Commission every three years and may update it more frequently as part of its ongoing planning process. The plan evaluates resource options using a range of assumptions and scenarios to inform long-term decisions about the company's energy portfolio.