ST. LOUIS — Ameren plans to build nuclear power sources for the first time in decades and add more gas-fired power generation than it previously expected to in a move utility officials say is necessary to satisfy potential large industrial customers.
By the 2040s the company said it intends to produce about 40% of its electricity from nuclear generation, 30% from gas and 30% from renewables, Ameren announced Friday. In contrast, 56% of its generation currently comes from coal plants built in the 1960s. Ameren Missouri chairman and president Mark Birk called the updated plan “an acceleration of things that we would’ve done in the future,” in an interview Friday. The utility had long planned to pour billions toward new generation — and largely renewable energy projects — over the next decade-plus, as it shifts away from burning coal. This plan marks a “significant change” in future power supply for the company, it said.
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Renewables and battery storage projects will remain a pillar of Ameren’s future energy mix, Birk said.
Gas and nuclear plants are more consistent and controllable power sources than wind or solar projects, Ameren officials said, in explaining the shift.
Ameren is responding to potential rapid increases in demand from large industrial customers, like data centers, that are exploring moves into its Missouri service territory.
“It’s really the new, large-load customers,” said Birk.
Ameren already has construction agreements that mark “an initial step” in securing potential large customers, but would not provide additional details Friday.
Looking farther ahead, lots of details remain unclarified about Ameren’s nuclear aspirations.
Birk said it is unclear which form of nuclear technology the company might embrace, moving forward — with emerging possibilities like “small modular reactors,” or SMRs, attracting some interest as potential alternatives to traditional nuclear plants that can carry notoriously massive price tags and technical challenges.
“We’re watching the development of the SMR technology,” said Birk. “We’d like to see a few more of those constructed. ... The SMRs have a little way to go, but we have some time.”
In Callaway County, near Jefferson City, Ameren currently owns and operates the lone nuclear power plant in Missouri, which has been in service since 1984. The company said that, in addition to planning for 1,500 megawatts of new nuclear generation by 2045, it also seeks an extension that would keep its Callaway facility running beyond 2044.
To make its goals a reality over time, Ameren’s plans to ultimately build new generation must first be approved by Missouri utility regulators.
Besides nuclear power, Ameren also intends to add more natural gas generation into the equation, accounting for 1,600 megawatts of new capacity by 2030. That includes the company’s previously announced plans to build a new, 800-megawatt gas plant for $900 million in south ӣƵ County, at the site of an old coal-fired power plant.
As recently as 2023, projected that gas would top out at around 14% of its future generation mix. Birk said the company has not determined where that other planned gas generation could be located.
He expects that the gas plants built by 2030 would serve mainly as “peaker” plants that run less than 20% of the time, typically when power demand is greatest.
And Birk said that building new fossil fuel generation like gas will not conflict with the company’s goals to slash its greenhouse gas emissions and become carbon neutral by 2045.
“It does help us continue to progress toward that goal,” he said, noting that gas is not as dirty as other fossil fuels such as coal, in terms of greenhouse emissions.
The company’s revised generation plans released Friday are “designed to provide for 1.5 gigawatts of expected new energy demand by 2032,” Ameren said in its release. For comparison, the company currently has around 10 gigawatts of capacity.
The new plans reflect “an overall increase of 1.8 gigawatts of capacity between now and 2030 and a total of 2.3 gigawatts of capacity by 2035,” plus energy generated by renewables, the company said.
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