11 data center developers in talks with NorthWestern, group says

Keila Szpaller

(Daily Montanan) Details about NorthWestern Energy’s plans to provide electricity to data centers in Montana still aren’t available to the public.

The monopoly utility is in talks with at least 11 more entities relating to data center development, including some in Montana, according to a growing coalition of groups that is raising concerns about data centers in the state.

NorthWestern Energy has provided the Public Service Commission three letters of intent with previously identified data center developers about its plan to provide them electricity, but most of the information is blacked out.

In a recent letter to the PSC, the coalition is calling on commissioners to require NorthWestern cough up more information about those deals, not just about the companies with which it’s already working, but about all the developers with interest in Montana.

Additionally, the City-County of Butte Silver Bow is urging the PSC to help prevent “boom-bust” fallout and to protect existing customers, including ones in Butte, from financial risk.

Atlas Power Group and Sabey have announced plans for data centers in Butte, and Quantica Infrastructure is working on a project outside Billings, according to earlier announcements from NorthWestern.

“We encourage the PSC to ensure that service to very large loads include appropriate conditions to protect overall system reliability and continuity of service for Montana households, businesses and public institutions,” said a letter signed by John Morgan, chairperson of the Butte-Silver Bow Council of Commissioners.

‘Demand more transparency from NorthWestern’

Data centers have sparked debate in Montana, as well as nationwide.

Proponents, including NorthWestern Energy, tout their potential for economic development, including more jobs and tax revenue.

Detractors, on the other hand, worry data centers will mean higher rates for existing customers and create a negative effect on other businesses and water users given their reliance on water for cooling.

A coalition represented by Earthjustice has said the PSC, which regulates monopoly utilities in the state, has a “statutory obligation to ensure that NorthWestern proves no adverse impact on existing ratepayers before agreeing to provide service to large load customers.”

In a letter Feb. 20, the coalition again called on the Public Service Commission to demand transparency from NorthWestern when it comes to data centers.

The letter also named a longer list of groups represented than a letter sent in the fall.

“Data center development is a growing concern for communities across Montana and groups with a wide variety of interests and perspectives are coming together to demand more information and ensure the Northwestern’s actions match its words when it comes to transparency and data centers,” said Lars Phillips, with Earthjustice.

The coalition is comprised of Big Sky 55+, Butte Watchdogs for Social and Environmental Justice, Climate Smart Missoula, Helena Interfaith Climate Advocates, Honor the Earth, Montana Environmental Information Center, and NW Energy Coalition.

The groups said they wanted to address the utility’s “inadequate response” to the PSC’s September 2025 request for “certain information ‘to ensure compliance with [statutory] requirements.’”

NorthWestern has referenced transmission service agreement studies and development agreements, but it hasn’t provided those to the PSC, and it should, the groups said.

“Based on its public statements, the utility both has ‘draft contracts or agreements’ with Sabey, Atlas and Quantica, and ‘executed agreements’ with Sabey and Atlas that are responsive to the (PSC’s) September 2025 Request but have not been provided to the Commission,” said the letter from Earthjustice.

The groups said the Public Service Commission should require NorthWestern to turn over any draft contracts that exist and also provide existing development agreements.

They also said the PSC should inform NorthWestern “that its obligation to provide documents responsive to the September 2025 Request is ongoing.”

“We encourage the Commission to expand the scope of documents that NorthWestern must provide to ensure the Commission is fully informed and able to carry out its oversight obligations,” the letter said.

The September 2025 request was tied to any documents between NorthWestern and entities referenced in press releases, but the groups said the PSC should ensure the utility submits documents with any data center developer.

It said NorthWestern has five steps for evaluating data centers— a request; a high level assessment; a contractual estimate; a completed contract; and construction.

“NorthWestern has indicated that both Atlas and Sabey are in the ‘contractual estimate’ stage, while Quantica is at the ‘letter of intent’ stage,” the groups said.

“As of Feb. 12, 2026, NorthWestern has also disclosed that there are six entities at the ‘data center request’ stage and five other entities at the ‘high-level assessment’ stage, at least some of whom are in Montana.”

It said the PSC should require NorthWestern to identify those entities and any other data center developers that are seeking electricity supply from NorthWestern in Montana.

“As the state agency empowered with broad, statutory authority to supervise, regulate and control public utilities, we urge you to demand more transparency from NorthWestern regarding its electricity supply service to data centers,” the letter said.

An ‘economic stability concern’ for Butte

In a separate letter to the PSC, the Butte Council of Commissioners said it supports a separate rate class “for very large electric loads.”

“This is necessary to ensure that the costs required to serve these loads are not shifted onto existing residential, small business, or public-sector customers,” the letter said.

Dated Jan. 16, the letter said the council supports clear and written “binding protections as a condition of service” to prevent ratepayers from “bearing financial risk if a project is delayed, reduced in size or abandoned after infrastructure investments have already been made.”

It said those protections could include commitments to cover the risk of “early exit or nonperformance.”

“These measures are important to protect both ratepayers and local communities from long-term financial exposure tied to development driven by rapidly evolving technologies with uncertain long-term requirements.”

The letter was signed by Council Chairperson John Morgan, who could not be reached Monday for additional comment.

However, the letter said the council is concerned about the potential impact the large loads may have on system reliability, especially during peak demand.

“Serving new large loads should not reduce service reliability for existing customers or increase exposure to emergency or high-cost power purchases,” the letter said.

The letter also noted two of the community’s largest employers rely on “significant and continuous electric service” (the letter didn’t name them). It said reduced reliability or higher costs could “place their operations (and the jobs they support) at risk.”

“Protecting system reliability and cost stability is therefore not only a ratepayer issue, but a direct economic stability concern for our community,” the letter said.

As such, the council called on the PSC to ensure safeguards that protect current customers and a transparent process.

NorthWestern says it will protect ‘all customer classes’

In an email, a NorthWestern spokesperson said the company isn’t serving any data centers yet, and it is taking steps to ensure existing customers are protected and rates remain fair.

“NorthWestern will not begin serving a new large‑load customer until the Montana Public Service Commission has reviewed and approved both (1) the applicable tariff and (2) the individual contract for service,” said NorthWestern Energy spokesperson Jo Dee Black in an email.

The utility is preparing a “large load tariff filing” for consideration by the Public Service Commission “to provide a clear, consistent framework for integrating new customers with significant energy demand, such as data centers,” into its system.

“The proposed Large Load Tariff filing will define the financial and contractual responsibilities of large-load customers and establish safeguards designed to protect all customer classes — particularly existing customers — from undue financial risk,” Black said in an email.

“In coordination with the Commission’s review and approval of electric service contracts for new large-load customers, the tariff will provide regulatory oversight and cost transparency, while ensuring that system growth is managed responsibly and costs are allocated fairly.”

NorthWestern did not address whether it plans to provide the documents requested in the letter from Earthjustice. It also didn’t address what information it is providing the PSC to help the commission ensure “no adverse impact on existing ratepayers.”

However, it said “NorthWestern Energy fully complies with all requests and requirements of the Montana Public Service Commission and operates within established regulatory processes.”

PSC spokesperson Jamey Petersen said Monday the commission has not had a chance to review the letter from Earthjustice yet. However, she said the PSC appreciates efforts to inform its investigation into data centers and will consider the information as it moves forward.