U.S. nuclear-power production rose for a second day as Entergy Corp. increased output at plants in Massachusetts and Louisiana.
Generation gained 1.2 percent to 92,450 megawatts, or 91 percent of capacity, the biggest daily gain since Jan. 13, according to U.S. Nuclear Regulatory Commission data compiled by Bloomberg. Output was 2.4 percent below a year ago, with eight of 104 plants offline.
Pilgrim 1, a 685-megawatt reactor 38 miles (61 kilometers) southeast of Boston, returned to full power from 17 percent capacity yesterday. Entergy shut the unit to investigate a valve leak three days ago, Carol Wightman, a spokeswoman based at the plant, said in an e-mail yesterday. Plant technicians replaced a pilot valve, she said.
The 1,250-megawatt Waterford 3 unit, which tripped offline Jan. 22, operated at 58 percent of capacity early today. The reactor, 25 miles west of New Orleans, shut after one of the steam generators reached a “low level condition,” a commission filing showed.
Output rose in three of the four NRC regions, while generation in the Midwest fell for a third day. The 1,261-megawatt Perry 1 plant operated by FirstEnergy Corp. 35 miles northeast of Cleveland tripped offline two days ago. The unit was at full power before its water level dropped, Jennifer Young, a company spokeswoman based in Akron, said in an e-mail at the time.
“The plant will remain shut down until the issue is fully understood and resolved,” Young said.
Reactor maintenance shutdowns, usually undertaken in the U.S. spring or fall when energy use is at its lowest, may increase consumption of natural gas and coal to generate electricity. The average refueling down time was 43 days in 2011, according to the Nuclear Energy Institute.