Ameren Missouri filed its 2026 Integrated Resource Plan with the Missouri Public Service Commission on September 28, and the headline change is coal. Two units at the Labadie Energy Center, previously slated to retire by the end of 2036, would now run until 2042 alongside the plant's other two units. The plan is nonbinding, and each project still needs its own approvals. Ameren is not the first utility to keep coal longer for this reason. In Maryland, a coal plant's life was extended to 2031 on data center load.
Behind the reversal is a surge in contracted demand. Ameren has signed electric service agreements covering 2.8 gigawatts (GW) of large-customer demand by 2030, mostly data centers, and it projects total load growth of 6 to 9 GW by 2045.
Ameren's Preferred Plan Adds About 10.6 GW of Gas Generation
The preferred portfolio, includes 2,100 megawatts (MW) of combined-cycle capacity by 2031, 2,800 MW more by 2035 and another 1,400 MW by 2042. Simple-cycle peaking plants add 1,900 MW by 2029 and 2,400 MW later in the planning period, with 500 MW of gas fuel cells also listed for 2030. Gas makes up the single largest share of new capacity in the plan.
On the cleaner side, the plan lists 1,300 MW of solar and 2,400 MW of battery storage by 2030, wind after 2030 and 1,200 MW of new nuclear by 2040. Capacity totals say little about how much each resource will actually generate or emit, since output depends on dispatch, fuel costs and which older units it displaces.
Ameren Makes Its 2045 Net-Zero Goal Contingent on New Technology
According to KBIA, the utility no longer expects to reach net-zero emissions by 2045 unless carbon capture or other mitigation technology advances. For companies with Ameren-served sites, that means the grid emissions factor behind their Scope 2 reporting may fall more slowly than earlier plans implied.
The Sierra Club had been pressing Ameren before the filing landed. Its annual Dirty Truth report, released this month, singled out Ameren Missouri over the cost and environmental harm of its coal fleet. That advocacy assessment reviewed utility plans as of mid-2026, so it does not grade the new filing. The group has scheduled an October 10 protest.
Missouri's Large-Load Tariff Shifts Growth Costs Onto New Data Centers
The tariff the commission approved in November 2025 applies to customers with at least 75 MW of monthly peak demand. They sign contracts of at least 12 years, with an optional five-year ramp, post collateral equal to two years of minimum monthly bills and pay exit fees if they leave early. Ameren also projects $21 million in savings for existing customers over two years from committed data center contracts, a company estimate yet to be tested in rate cases.
Texas took a different route on several of these terms, as a comparison of large-load tariff rules in the two states lays out. Nationally, 23 states have now settled who pays for the data center buildout in some form. For existing commercial and industrial customers in Missouri, the commission's review is the next checkpoint. Cost allocation will get its hardest look there, especially the question of what happens if forecast demand never shows up.
