U.S. Sen. Josh Hawley introduced a bill Wednesday that would require data centers to have their own power sources in order to shield other customers from seeing their bills go up.
The Guaranteeing Rate Insulation from Data Centers Act would also require that consumers are prioritized before data centers for electricity and require data center operators to publicly disclose their current and future utility use.
"American families should not have to shoulder the burden of the rising electricity costs produced by data centers in Missouri and across the country," Hawley said in a statement. "This is unacceptable."
Experts say customers are at risk of seeing higher electricity bills from data centers because the massive power users will require new, expensive power plants. Typically, costs to build power plants are spread out across all customers in rate increases, meaning customers could foot the bill for plants built for data centers.
The Republican senator introduced the bipartisan legislation with Sen. Richard Blumenthal, D-Connecticut. It would apply to data centers that use 20 megawatts of power or more.
Ameren Missouri is building multiple new power plants, including a natural gas and battery storage energy center that was approved Wednesday. In filing documents, Ameren officials have said some of the projects are, in part, for large-load customers like data centers.
"The Big Hollow Projects are needed to provide reliable service to all of our customers, due to the likelihood that we will add customers with significant new large loads in just the next few years," wrote Ajay Arora, senior vice president and chief development officer.
Ameren did not immediately reply to a request for comment on the legislation.
In November, Missouri's Public Service Commission approved a special rate structure for data centers moving to Ameren's territory. The rates were designed in response to a new Missouri law requiring utilities to protect existing customers from having their electricity go up because of data centers.
"We're going to do everything that we possibly can to reasonably ensure that these customers are paying their fair share, and that we're not unjustly passing costs on to other customers," Rob Dixon, Ameren's senior director for economic, community and business development, said soon after the company proposed the new policies.
But an advocacy group, the Consumers Council of Missouri, said the rates did not do enough to protect households and filed for a rehearing.
"In our opinion, the Public Service Commission has gone too far in promoting economic development for these data centers and not protecting other customers," John Coffman, an attorney for the Consumers Council, said at the time.
The commission denied that request, and the Ameren data center rates are now in place.
At least one local company is already considering operating this way. Mastercard's largest U.S. data center is in O'Fallon, Missouri, and the company said it will power it with solar energy in a closed system, separate from Ameren.
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