Ameren Missouri files 20-year plan with 10.6 GW of gas additions

Ameren Missouri, which serves about 1.3 million customers in the central and eastern part of the state, has filed a 20-year plan with state regulators that leans heavily on natural gas. The plan would take gas from about 5% of the utility's power mix today to 60% by 2045, while phasing out coal entirely. Ameren plans to add 10.6 gigawatts of new gas plants, along with 3.6 gigawatts of solar, 1.5 gigawatts of wind, 2.4 gigawatts of battery storage, and 1.2 gigawatts of new nuclear power. The utility also expects to seek an extension to keep running its Callaway nuclear plant past 2044.

Ameren says the buildout is driven largely by expected growth from data centers and other large energy users, which it expects to nearly double its committed large-load demand by 2030. Company leaders say mixing different power sources helps keep the grid reliable and costs in check. Environmental groups disagree, arguing the plan deepens reliance on fossil fuels and could delay retiring the utility's Labadie and Sioux coal plants, which are now set to close by 2042 and 2035.

For homeowners in Ameren Missouri's service area, this plan is a long-term signal about where electricity supply is headed, not an immediate change to your bill or your home. But it's worth knowing that Ameren filed a separate $343 million rate increase request in June that could raise residential monthly bills by about 10%, according to local news reports. That rate case, not this 20-year plan, is the more immediate thing to watch if you want to know what might show up on your next bill.