Montana Governor Greg Gianforte and the state Department of Environmental Quality announced Thursday they will seek to formally intervene in a Public Service Commission proceeding examining how large electricity users — primarily data centers — should be charged for power and grid access.
Background on the Tariff Proposal
NorthWestern Energy filed a request with the PSC in March seeking approval for what it calls a “large new load tariff,” which would establish new rules for any commercial customer purchasing five megawatts or more of electricity. Under the proposed framework, large-load buyers would face minimum service periods and billing minimums tied to both demand and energy consumption.
Customers seeking more than 50 megawatts of power would face longer minimum service commitments than smaller buyers under the threshold. The proposal is designed to ensure that companies connecting at scale bear the infrastructure costs their usage requires rather than spreading those costs across the general ratepayer base.
The scale of potential demand driving the proceeding is striking. Quantica Infrastructure has disclosed plans for a data center campus north of Billings projected to consume 1,100 megawatts of electricity — a figure that dwarfs NorthWestern Energy’s current total Montana supply of roughly 750 megawatts.
State’s Role in the Proceeding
The DEQ’s energy office is seeking intervenor status, which would allow it to submit technical testimony, file evidence, and negotiate directly with other parties on questions of customer protections and grid interconnection requirements for large incoming projects.
Governor Gianforte framed the state’s involvement around protecting residential customers from bearing costs generated by large commercial users. “We’re making sure large, new power users pay their own way so Montana families aren’t left subsidizing their electric bills,” he said in Thursday’s announcement.
DEQ Director Sonja Nowakowski said the proceeding is an opportunity to shape a grid access system that serves both economic development and fairness. “Montanans deserve a system where large, new customers can connect to the grid quickly while covering the full incremental costs of serving them,” she said.
Other Parties Seeking a Voice
The state is not alone in wanting a seat at the table. Climate Smart Missoula, Earthjustice, and the Montana Public Interest Research Group have also submitted requests to intervene in the PSC hearing. The environmental groups’ priorities likely diverge from the state’s, suggesting the proceeding will involve a wide range of competing interests before the commission.
Those groups are also pursuing a separate but related legal challenge. They have contested a PSC protective order that allows NorthWestern Energy’s data center letters of intent to remain sealed from public view. That case remains pending.
Broader Demand Picture
The Montana PSC proceeding is unfolding against a regional backdrop of rapidly escalating electricity demand. The Western Electricity Coordinating Council projects that power demand across the western United States will grow by roughly 20 percent over the next decade — more than double the nine percent growth projected in a similar analysis from three years ago. Data center expansion, driven by artificial intelligence infrastructure buildout, is a leading factor in those revised forecasts.
Montana’s relatively low electricity costs and available land have drawn interest from data center developers, making questions about grid cost allocation directly relevant to the state’s ongoing population and economic growth. How the PSC ultimately structures cost responsibilities for large new loads will likely shape whether that interest translates into actual development — and on what terms existing Montana ratepayers experience it.
The PSC has not yet set a schedule for the hearing, and it has not yet ruled on any of the pending intervention requests, including the state’s. The DEQ’s formal request is expected to be filed in the coming weeks following Thursday’s announcement.
