Ameren Missouri's 20-year plan adds 10.6 GW of gas as large loads grow deliveries 60% by 2030
Victoria Shinder2 min readAmeren Missouri filed a 20-year integrated resource plan with the Missouri Public Service Commission on 28 September that rebuilds its generation around natural gas to serve a surge in large customers, mainly data centres, Utility Dive reported.
The load behind it. The utility, which serves about 1.3 million customers in central and eastern Missouri, says large loads will grow its base customer deliveries by 60% between 2027 and 2030, with annual sales growth of 5% to 6% over the plan. It has committed to serve 2.8 GW of large-load demand by 2030, almost double the 1.5 GW in its 2025 expectations. Its base case for large-load deliveries rises from about 1,400 GWh in 2027 to 44,676 GWh in 2046, a compound annual growth rate of 20%. Ameren says Missouri law and its own plans include provisions to make these customers cover the cost of the infrastructure built for them.
What it plans to build. In total, about 10.6 GW of gas, taking gas from roughly 5% of its resource mix today to 60% by 2045:
- combined-cycle plants: 2,100 MW by 2031, 2,800 MW more by 2035 and 1,400 MW more by 2042;
- simple-cycle plants: 1,900 MW by 2029 and 2,400 MW after 2040;
- 500 MW of gas fuel cells by 2030. Alongside the gas: 1,300 MW of solar by 2030 and 2,300 MW more by 2045, 2,400 MW of battery storage by 2030, 1,500 MW of wind after 2030 and 1,200 MW of new nuclear by 2040, with neither a site nor a technology chosen. Ameren also expects to seek an extension for its Callaway nuclear plant beyond 2044.
Coal. All coal capacity retires: Sioux by the end of 2035 and the four Labadie units by the end of 2042. Environmental groups noted the plan keeps options to extend both, and the Sierra Club called it pollution-heavy. Ameren says it had to make good-faith assumptions about environmental rules because of regulatory uncertainty, as the federal government rolls back limits on coal and gas plants.
Context. Ameren files its plan every three years. In June it filed a $343 million rate increase that, according to local reports, could raise residential bills by about 10%.
What it means
This is what data-centre demand looks like inside a single vertically integrated utility: a load forecast growing 20% a year drives a gas build that dwarfs every other resource. Regulators reviewing the plan will need to test the 2.8 GW commitment and the cost-allocation promise, because if the large loads arrive later or smaller than forecast, the gas plants will still be in the rate base.