By Amanda Eggert, Montana Free Press

The Colstrip power plant and ash ponds, photographed in 2019. Credit: Alexis Bonogofsky / MTFP
The agreement will give Montana’s largest utility a 55% stake in the state’s largest power plant.
NorthWestern Energy announced this week that it will acquire a large share of the Colstrip power plant from Puget Sound Energy, a Washington-based utility facing a mandate to stop using coal-generated power by 2025.