Ameren Missouri wants to significantly ramp up power plant construction to meet data center electricity needs, according to a 20-year plan released this week.
The new plan significantly increases the company's reliance on natural gas plants while scaling back the percentage of energy produced by renewable sources like wind and solar. And in a change from previous plans, the company is no longer discussing a goal to reach net-zero carbon emissions.
Monopoly utilities publish these plans, called Integrated Resource Plans, every three years as required by Missouri law. This plan is now a case before the Missouri Public Service Commission, which will include pushback from outside parties and public comment submitted to regulators before being finalized.
Data center growth
There are currently 40 potential large data centers that could be built within Ameren Missouri's footprint, according to the document, including multiple projects that have signed binding agreements with the company.
New data centers represent the majority of the company's projected growth over the next 20 years, said Ajay Arora, executive vice president, chief growth officer and chief generation development officer for Ameren Missouri.
He said those projects could benefit regular consumers.
"Economic development is vital to the state," Arora said. "It helps us modernize our electric grid to ensure reliability for everybody and have that fixed cost be spread over new customers."
To meet that new demand, Ameren is planning to build power plants and renewable energy projects that would generate almost double the amount of electricity it was projecting to build in its 2023 projection.
Shifting climate goals
In 2020 and 2023, Ameren focused its planning on renewable energy, discussing goals to reach net-zero carbon emissions. Ameren removed that language in the 2026 Integrated Resource Plan, discussing how its plan will decrease carbon emissions, but saying technology like carbon capture would have to advance to achieve net-zero emissions.
"We are not changing our net-zero targets right now," Arora said. "However, we do outline in the plan that new technology would need to mature in order for us to achieve our net-zero goals."
Much of the new power would come from natural gas — in 2023, the Integrated Resource Plan called for two such plants. In 2026, the new plan lists nine plants to be built over the next two decades.
Environmental advocates took issue with that new focus on natural gas, including Jenn DeRose, the Sierra Club's campaign organizing strategist for Beyond Coal in Missouri.
"Their own research shows that solar and wind are the cheapest forms of energy to build, and they're still choosing gas," DeRose said. "I find that very interesting. I also find it very interesting that they cite extreme weather as a reason for building gas. Do you know what causes extreme weather? Climate change. Do you know what contributes to catastrophic climate change? Coal and gas."
Ameren Vice President of Regulatory and Legislative Affairs Rob Dixon said a reliable energy system needs a diversity of energy sources.
"It's really important to remember that no single technology type can meet every customer need in every hour under every condition," Dixon said.
Increasing renewables and keeping coal
The 2026 Integrated Resource Plan also increases the company's renewable energy buildout, with new solar plants and battery storage.
"They are adding solar, they are adding batteries, and I think that's good," said James Owen, executive director of Renew Missouri. "I think that makes sense for long-term considerations. But I think the continued reliance on fossil fuels is going to end up costing customers more money than Ameren is currently anticipating."
For the IRP, Ameren calculated the lifetime costs of each source of new energy it is considering building. The company found wind, solar and the kinds of natural gas plants that run consistently were the least expensive per kWh, while nuclear plants and the kind of gas plants that can turn on and off, potentially to supplement renewables, were the most expensive.
The new plan also extends the lives of two coal plants. The Sioux Coal plant would close three years later than planned in 2023, while the Labadie plant would keep all four units operational until 2042, when two were originally set to retire in 2035.
Arora said that decision was made to save money.
"Labadie remains one of the most affordable plants in the country and recognizing the economic conditions for all our customers and how important reliability and affordability is, that's really factored into delaying the retirement of a few of the Labadie units by a few years," he said.
Environmental advocates said there are other costs that come with coal.
"Do you know why that plant is so affordable?" DeRose said. "It's because it doesn't have any modern pollution controls. So it's only affordable for the company. Those health externalities, those are what we have to pay for."
Paying for new plants
To actually build power plants or to set new electricity rates, Ameren still has to take each request to the Public Service Commission as a case.
While this plan does not change people's bills, Owen said the cost of the new power plants will trickle down to customers eventually.
"Any time they build more generation, it's going to increase rates," Owen said. "I don't know how they can say that, 'Oh, this is [only costing] data centers,' when that's the main thing driving energy consumption right now. It's not that we're having this huge influx of people moving into Missouri. It is not this huge influx of other manufacturing jobs. It's data centers."
Ameren's representatives said a Missouri utility law known as Senate Bill 4 requires data centers to pay for the infrastructure to serve them and said the companies do not receive discounted electric rates.
"The safeguards in Senate Bill 4 are meaningful," Dixon said. "That's exactly what ensures that other customers are not bearing the costs caused by data centers. And in fact, we've done some projections, and we expect that our customers are going to see projected savings of $21 million over the next two years driven by the data center customers that we've already committed."
The Sierra Club's DeRose wants more people to get involved in the utility planning process and is organizing a protest against Ameren on Oct. 10.
"They need to hear your voice, the average customer's voice, if we're going to see the company change its ways and change its addiction to fossil fuels into something that is more sustainable for our future," DeRose said.
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