The state’s largest energy utility lost a main source of power generation last week, during a multi-week heatwave. The Colstrip plant is back up and running, as temperatures are forecasted to rise again.
Colstrip Units 3 and 4 came back online on Saturday. Unit 3 had been down for 10 days to address a maintenance issue. Unit 4 was offline for four days, also for an unknown maintenance issue, as MTPR previously reported.
NorthWestern spokesperson Jo Dee Black said the maintenance issues that shut down both units were “separate” and “an unfortunate coincidence”. Coal-fired power makes up almost 27% of the utility's energy portfolio.
When NorthWestern is unable to generate enough power to meet demands, it can purchase energy on the open market. That energy can be more expensive and costs are passed on to consumers. Reports this fall will show how much the utility spent on the open market.
Many areas in the state are expected to see temperatures climb back into the triple digits this weekend. When asked about concerns for Colstrip being affected by extreme heat, Black wrote that the plant has been able to serve customers when needed, 95% of the time.
