Xcel Energy said it could be weeks before its Black Dog generating plant is back on line.
A fire and explosion at a coal storage area shut down the Burnsville generating plant on Tuesday. Company officials said there was initially a fire, then a blast that tore the west side of the building open.
Three firefighters suffered minor injuries in the explosion.
Xcel Energy spokesman Tom Hoen said today that the company was still working on an assessment of what happened and what was damaged by the incident.
He said workers were also trying to make temporary repairs ahead of an expected storm this week.
"What we're doing today is sealing up the exterior as much as we can, and then we are also going to be putting in temporary protective structures inside the plant to protect that area, the equipment that was effected," Hoen said.
Hoen said that Xcel will increase production at other plants or buy power on the open market to make up for the Burnsville shutdown.