NorthWestern Energy signs agreement for North Plains Connector megawatts

NorthWestern Energy announced Thursday it is joining a new high voltage transmission project that will help expand Montana’s grid and meet the state’s increasing energy demand.

In a news release, the utility said it plans to own 10% of a 3,000 megawatt transmission line to be built from Bismarck, North Dakota, to Colstrip, and it signed a nonbinding memorandum of understanding with North Plains Connector.

Grid United and ALLETE are jointly developing North Plains Connector, and Avista, Portland General Electric and Puget Sound Energy also have ownership agreements with North Plains Connector.

In the news release, energy executives lauded the announcement as a boon for Montana communities, and in a phone call, a legislator from Colstrip said the deal will help customers in Montana get reliable energy, although more needs to be done.

“NorthWestern Energy’s Colstrip, Montana, substation is strategically located and will serve as a critical endpoint for North Plains Connector, reinforcing Colstrip’s position as an essential energy hub,” said NorthWestern Energy President and CEO Brian Bird in a statement.

“The North Plains Connector developer’s collaborative approach with Montana communities to address concerns and ensure the footprint reflects local priorities aligns with NorthWestern Energy’s commitment to our customers.”

Colstrip is home to a coal-fired power plant, and NorthWestern notes it will own 55% of it as of January 2026.

Rep. Gary Parry, R-Colstrip, said he wishes NorthWestern was getting more than 300 megawatts, but the deal will help Montana during times like the cold snap in January earlier this year.

Montana doesn’t have sufficient incoming transmission, so it gets the short end of the stick when bidding is high, Parry said. He said even wind projects in Montana are tying into the lines here but sending power straight to the coasts.

“Right now, since Montanans don’t really have any ownership on those lines going to the coast, it helps none of our Montanans,” Parry said.

Parry, slated to serve as chairperson of the Montana House committee that handles energy, said North Plains Connector isn’t too far from breaking ground. Still, he said it’s possible the 2025 Montana Legislature could help streamline the process.

“I think legislators have a responsibility to make sure we figure out how to make reliable, dependable power available to the citizens of the state,” he said.

The news release described North Plains Connector as “the first interregional transmission line to create a major grid-to-grid connection across the three energy markets.” It said the transmission line will create connections between NorthWestern’s Montana and South Dakota service areas.

“NorthWestern Energy is the only partner serving customers in both regions, which have diverse energy load demands and diverse energy generation resources,” said Bird in a statement.

NorthWestern said the bidirectional transmission line “will efficiently transport large amounts of power from areas with supply to areas in need and take advantage of diverse load and weather patterns.”

The project is entering the permitting phase, construction is expected to start in 2028, and the goal is for North Plains Connector to be running by 2032, the news release said. The announcement said Grid United will fund the development, and NorthWestern will invest when regulatory approvals and permits are in place.

“We are pleased to welcome NorthWestern Energy to North Plains Connector,” said Michael Skelly, CEO and co-founder of Grid United, in a statement. “As Montana’s largest energy provider, NorthWestern Energy brings a breadth of experience and deep understanding of the region’s energy needs. Their support reinforces the importance of North Plains Connector as a meaningful solution for a strong and reliable electric grid.”

The news release said NorthWestern Energy and Grid United also plan to continue transmission development to further enhance the grid through the southwest corridor of Montana.

“Development to expand the southwest corridor of Montana through grid buildout would represent a significant step in enhancing connectivity between Montana and the broader Western energy market — bolstering grid reliability, allowing for critical import capability and enabling customers to access and benefit from emerging energy markets in the West,” the news release said.