Missouri Data Center Demand Spurs Costly Grid and Gas Buildout

A state rebuilds its grid around data centers

Until recently, Missouri barely registered as a data center market. Now it is planning its power system around them. Over the past several weeks, state officials, federal energy leaders and the state's largest utility have released a series of plans that point the same way: AI data centers are becoming the main reason Missouri needs more power plants, more transmission lines and grid upgrades worth billions of dollars. Those plans have not settled who will pay for it.

The new state energy plan says Missouri has gone from a "minor data center market to a rapidly expanding hub." Most construction is in the Kansas City corridor, and more projects are planned along Interstates 70 and 44.21 The plan's model expects the state's electricity load to double over the next 25 years, partly because of new data centers.27 It also finds that Missouri would need to generate 2.6 times as much energy as it does today to replace retiring plants and meet projected demand.23

The utility filings are even more striking. Ameren Missouri's new 20-year Integrated Resource Plan, filed with the Missouri Public Service Commission on Sept. 28, includes 10.6 gigawatts of new natural gas generation.6 The utility names data center expansion as the main driver of its load growth.25

The numbers behind the surge

The estimates of how fast demand will grow are large. Market intelligence firm Cleanview counts 11 data centers expected to be running in Missouri by the end of this year, drawing about 340 megawatts. The 50 projects planned after them would raise that figure to more than 7,400 megawatts, roughly a twentyfold increase. By Cleanview's estimate, the average new facility running at a typical two-thirds of capacity uses as much energy as 54,000 homes.

Ameren's own forecast is just as steep. In its base case, deliveries to large-load customers grow from about 1,400 gigawatt-hours in 2027 to 44,676 gigawatt-hours by 2046, a compound annual growth rate of 20%.6 The plan lists 40 potential large data centers inside Ameren Missouri's territory, and several have already signed binding agreements.7 A regulatory affairs director at the utility has said that by the end of 2029 these new customers could use more than half as much electricity as all of Ameren's other customers in eastern Missouri combined.2

The contracts are already signed. In February, Ameren signed confidential agreements covering 2.2 gigawatts of new demand, which is nearly the full capacity of its Labadie coal plant, its largest power station.10 By its second-quarter earnings presentation in July, the total had reached 2.8 gigawatts of executed Electric Service Agreements. The company also reported another 0.6 gigawatts under construction agreements and 4 gigawatts of proposed projects with completed interconnection studies.9 The two largest names are well known: Google is pursuing a $15 billion data center project in Montgomery County3, and Amazon has announced a $10 billion campus in Montgomery City.8

On the western side of the state, the projects are just as large. Google's Project Mica in the Northland could draw up to 500 megawatts. Nebius received more than $6 billion in tax breaks for an 800-megawatt campus in Independence that will eventually run on its own natural gas plant at the retired Blue Valley site.

What the buildout looks like

The clearest change in Ameren's plan is how much it now relies on gas. The 2023 version called for two natural gas plants. The 2026 version lists nine over the next two decades, and it also lowers the share of power expected from wind and solar.25 The plan removed language about reaching net-zero carbon emissions that earlier versions had included. An Ameren executive said the company's targets have not changed but that new technology would have to mature before they can be met.25 The plan still adds solar and battery storage, which Renew Missouri's James Owen called sensible, while warning that continued reliance on fossil fuels will cost customers more than Ameren expects.25

The wires behind those plants are also expensive. Ameren's plan includes $5.2 billion in transmission and distribution spending from 2026 through 2030 for smart grid technology, system hardening and replacing aging equipment.5 The company says that in growing areas, some of its infrastructure is already at or near capacity. About 20 substation devices have to have their automatic transfer schemes disabled during summer peaks, and about 40 during winter peaks.5 Separately, Ameren filed for 3 gigawatts of new generation, including the proposed 2.1-gigawatt West Alton combined-cycle gas plant, which would be one of the largest projects in its history.9

The national picture adds more pressure. The federal National Transmission Needs Study, which Department of Energy officials discussed in Jefferson City, says about 4,000 miles of power lines will need to be replaced every year for decades. It projects U.S. electricity use rising 16% to 25% by 2034, driven largely by data centers.22 At the regional level, the Midcontinent Independent System Operator expects to add 15 gigawatts of summer capacity each year for the next five years.26

The fight over who pays

This is where the coverage splits most clearly, and where the story matters most for Missouri households.

The utilities and state law point to protections. Senate Bill 4, passed in 2025, required the Public Service Commission to set rates for large-load customers that reflect what it costs to serve them and that keep unjust costs off other customers.14 Both Ameren and Evergy now have approved large-load tariffs. They require 12-year minimum contracts, with an optional five-year ramp-up period. They also include collateral equal to two years of minimum bills, exit and early termination fees11, and a monthly demand charge set at 80% of the contracted amount.14 Ameren's tariff also requires data centers to pay for their own substations and transmission lines. If the utility's returns from large customers exceed a set threshold, 65% of the excess goes back to customers, with 15% set aside for low-income households.17

Ameren says these rules are working and projects that existing customers will save $21 million over the next two years because of data center customers it has already signed.25 Evergy similarly lowered a pending Missouri rate request by $25 million based on revenue it expects from large data centers in 2026, and it says that rate case does not include any costs of serving data centers.12 Data centers have also paid Ameren $46 million in nonrefundable payments to cover transmission upgrades.10

Consumer advocates do not accept that the protections are enough. Geoff Marke, chief economist at the Missouri Office of Public Counsel, wrote earlier this year that data centers have already raised utilities' costs through socialized transmission charges, volatile wholesale markets and spending on generation driven by unprecedented demand.2 He has said transmission is the part of the debate that "largely gets glossed over," even though ratepayers end up carrying it.22 He has also questioned in regulatory filings whether some of the proposed power plants exist only to serve AI demand.24 Owen put it more bluntly: data centers are the main reason consumption is growing, so new generation costs cannot be separated from them.26

The disagreement has a history. When regulators approved Evergy's tariff in November 2025, the Public Service Commission's own staff and the Office of Public Counsel both opposed the order.15 The commission rejected the staff's alternative proposal as too complex and said it could push large users out of the state16. It also declined to cap the share of load large customers could make up.18

Customers are already seeing higher bills while this plays out. Ameren Missouri is asking for a $343 million revenue increase to pay for reliability investments9, which one analysis estimated could add about $13 to monthly bills.2 Across the Midwest, utilities have requested about $3 billion of the $18.6 billion in rate increases sought nationwide so far in 2026.26

Reading the signals

The stronger reading of this coverage is that SB 4 tariffs protect customers well against the direct costs of hooking up a single data center, and much less well against the costs that come with the whole system growing. Contracts, collateral and exit fees reduce the risk of stranded assets if a specific customer leaves. They do less about regional transmission costs that are spread across a pricing zone. More than 90% of one category of Ameren's transmission revenue requirement is assigned to its Missouri zone and paid through retail rates.5 Ameren's own plan also shows that the utility's growth strategy depends on adding to its rate base. Its five-year capital plan includes $21.3 billion for Ameren Missouri alone.9

There is also real uncertainty about whether all this demand will show up. Analysts quoted by Axios said as many as half of the data centers scheduled to open worldwide this year could be delayed, and 45 projects on Cleanview's list have already been canceled. If much of Missouri's pipeline disappears after nine gas plants have been committed to, the cost protections will face their first real test.

State leaders see an opportunity. Missouri uses about eight times more energy than it produces, and Gov. Mike Kehoe's administration wants to reverse that with new nuclear plants and "priority energy zones" on brownfields and former power plant sites.23 The energy plan argues that building generation in the state, though costly, could slow future bill increases compared with continuing to import power.21 Google, for its part, has committed $20 million to energy affordability programs and says it will pay all of the power costs for its operations.24

Whether those commitments hold up is now a question for regulators. Ameren's 20-year plan is open for outside challenge and public comment25, and every plant in it will need separate approval. The outcome of those cases will show whether Missouri's data center boom ends up paying for itself or adds to residents' bills.