SCHROEDER, MN ((KDAL) -  Emergency responders were called to Minnesota Power's Taconite Harbor Energy Center in Schroeder Monday morning after a fuel system explosion.  The blast was confined to the plant's coal storage bunkers and injured a 41 year old Fuels Technician who was in the room at the time.  The Minnesota Power employee, identified as Joe Fredrickson,  was taken to the Cook County North Shore hospital in Grand Marais and later transferred to a Duluth hospital.  The extent of the injuries are not known at this time.  The power plant was temporarily evacuated as a precaution and Minnesota Power is investigating the cause of the incident.