The 860 MW Unit No. 3 at Xcel Energy's coal-fired power plant in Sherburne County, Minnesota has returned to service for the first time since 2011.
The unit was brought offline in November 2011 for turbine testing after being restarted following scheduled maintenance. The failure damaged the turbine and associated power plant systems, according to Xcel.
Workers had to repair the extensive cracking they discovered in a row of turbine blades caused by a design flaw unrelated to the operation of the turbine, according to Xcel.
The utility said most of $200 million repair bill should be reimbursed by insurance