Today, the Public Service Commission of Wisconsin (PSC) decided that all future hyperscale data centers in Alliant Energy’s service territory must be served through a standardized tariff, rather than individual contracts.
Clean Wisconsin intervened in the case to oppose Alliant’s proposal to rely on a one-off contract negotiated behind closed doors. Instead, Clean Wisconsin advocated for the use of a tariff: a standardized pricing structure that defines how classes of customers, such as “very large customers” like data centers, pay for electricity and the infrastructure needed to serve them.
While the PSC approved a modified version of Alliant’s special contract with Meta to serve its Beaver Dam data center, it ordered the utility to file a tariff proposal for all data centers over 100 megawatts going forward.
“Tariffs create a consistent, transparent framework that helps protect the public interest,” said Clean Wisconsin Staff Attorney Brett Korte. “Without them, Wisconsin risks a patchwork system where costs and responsibilities are unclear and potentially shifted onto other utility customers.”
Properly designed tariffs can help ensure data centers fully pay for the infrastructure and energy resources required to serve them, while also creating opportunities to integrate more clean energy and reduce strain on the grid through flexible solutions like energy storage and demand response.
As more data centers are proposed in Wisconsin, Clean Wisconsin says regulators must rely on transparent, standardized tariffs that clearly define how large customers pay for electricity and infrastructure while also protecting the environment.
“While the PSC approved Alliant’s contract, with modifications, for Meta’s Beaver Dam data center, they recognized that continued one-off, bilateral contract negotiations are not sufficiently protective of Wisconsin families and small businesses,” said Korte.
Today’s decision follows a recent ruling in which the PSC required We Energies to modify its proposed data center tariff following intervention by Clean Wisconsin to strengthen protections for ratepayers and better enable the use of clean energy resources. Together, these two cases will shape how Wisconsin regulates a rapidly growing class of “very large customers.”
“As data centers continue expanding across Wisconsin, the decisions regulators make now will determine whether utility customers are protected from rising costs and whether this new demand accelerates investment in cleaner energy resources,” said Korte.
