The Tennessee Valley Authority (TVA) Sequoyah Nuclear Plant has returned its Unit 1 reactor to operation after successfully completing more than 10,000 activities designed to enhance the safety and reliability of the unit, TVA said May 18.
Unit 1 returned to operation on Saturday, May 16. Sequoyah had started its refueling outage on April 11, meaning that it was out-of-service for about 35 days.
The unit was listed at 74% generation early May 18, according to Nuclear Regulatory Commission (NRC) data. Sequoyah Unit 2 completed its last refueling outage in June 2014.
Nine of the nation’s 99 commercial nuclear units were listed at zero generation on May 18. Most of them were offline for refueling-related outages.
In addition to refueling, the TVA successfully completed a detailed 10-year inspection of the reactor vessel and its internal components. The team also added a number of enhancements to the station’s emergency operation capabilities.
“Although safely refueling the reactor was our key activity, the primary focus is always on improving the safety and reliability of plant equipment,” said John Carlin, site vice president. “Team members refurbished or replaced more than 500 individual valves, electrical breakers and motors, some of which can only be accessed when the unit is offline.”
In addition to refueling, the site successfully completed a detailed 10-year inspection of the reactor vessel and its internal components. The team also added a number of enhancements to the station’s emergency operation capabilities.
At full capacity, Sequoyah’s two generating units provide a combined 2,200 MW of electricity, enough to power 1.3 million homes across the Tennessee Valley. Sequoyah Units 1 and 2 are pressurized water reactors located in Hamilton County, Tenn.
The Sequoyah nuclear units are seeking a 20-year license renewal from the NRC. The current licenses for Units 1 and 2 expire in September 2020 and September 2021, respectively.
TVA also operates three units at the Browns Ferry Nuclear Plant near Decatur, Ala., and one unit at the Watts Bar Nuclear Plant near Spring City, Tenn. A second unit is currently nearing completion at Watts Bar and is scheduled for fuel load later this summer.