2014 top stories: #3 - Prairie Island marks 40 years of power
Staff at Prairie Island nuclear plant kept busy in 2014. Between finishing a refueling outage in January and starting another one in October, the Xcel Energy facility celebrated 40 years of operation with an open house in July.
“Prairie Island has been delivering safe, reliable and clean service for 40 years, but we couldn’t have done that without all of you,” said Dave Sparby, the retiring president of Northern States Power Co. — Minnesota, to community members during a luncheon at the plant’s training center.
After going online in the mid-1970s, the 520-acre nuclear plant located down the road from Treasure Island Resort & Casino has gone through a number of upgrades — many involving security enhancements following September 11, 2001, terrorist attacks.
Security was the focus of a hostile action drill conducted in August at the plant and in surrounding communities. A preliminary assessment by the Federal Emergency Management Agency and U.S. Nuclear Regulatory Commission gave Xcel Energy staff and area first-responders a positive performance review.
Xcel Energy also upgraded generating equipment in the plant, including installing two steam generators for the Unit 2 reactor during a refueling outage completed Jan. 13.
Unit 1 was up for refueling in the fall, going offline shortly before 1 a.m. Oct. 8. The outage marked the reactor’s longest operating period at 644 days.
Along with replacing about one third of Unit 1’s fuel assemblies, staff and around 600 outside contractors completed maintenance tasks and installed a new transformer.
Xcel Energy announced Unit 1 returned to full power at 2:02 p.m. Nov. 28.
Refueling outages are planned around every 18-22 months, and staggered to allow one reactor to remain online. To make up for the lost power, Xcel Energy purchases electricity from the Midcontinent Independent System Operator or other utilities, or increases electricity production at its other plants.
Crews had shut Unit 1 down again Dec. 10 to replace a reactor coolant pump seal. Unit 1 returned to full power on Monday, Xcel Energy said.
When both units are operating, they generate enough electricity to power 1 million homes, Xcel Energy says.
Also this year Xcel Energy announced the completion of a 77,000-square-foot administration building at the plant. The building, which went into service in December, houses departments that had been working out of office trailers for years.
Recent improvements at the plant increased its assessed property value, something both the city of Red Wing and Goodhue County capitalized on this year to collect more tax dollars from Xcel Energy without significantly affecting other taxpayers.
Prairie Island nuclear plant entered its extended federal licensing period this fall. The twin reactors can operate until 2033 and 2034.
Xcel Energy says it plans to continue upgrading plant safety, including the purchase of diesel pumps to deliver water in case of catastrophes like the 2011 Fukushima plant incident in Japan.
Unit 2 refueling and transformer replacement is scheduled for fall 2015.