Exelon Corp. increased production at the Oyster Creek 1 reactor in New Jersey, leading U.S. nuclear-power output to the highest level in almost three months.
Generation nationwide advanced by 1.5 percent to 86,653 megawatts, or 85 percent of capacity, the highest since Sept. 15, according to U.S. Nuclear Regulatory Commission data compiled by Bloomberg. Output was 7.1 percent lower than a year ago with 12 of the 104 nuclear reactors offline.
Exelon’s 619-megawatt Oyster Creek 1 operated at 74 percent of capacity today, up from 22 percent yesterday. The unit is increasing output after completing a refueling shutdown that began Oct. 21, said Suzanne D’Ambrosio, a company spokeswoman based at the plant.
Two pipe weld issues were detected and repaired while the unit was shut, she said. Oyster Creek 1 is about 33 miles (53 kilometers) north of Atlantic City.
The 621-megawatt Nine Mile Point 1, a Constellation Energy Group Inc. reactor, was operating at 75 percent of capacity as of 8 a.m., Jill Lyon, a company spokesman based in Scriba, New York, said in an e-mail. The reactor, near Oswego, ran at 37 percent earlier today. It completed a shutdown for turbine repairs on Nov. 30.
Entergy Corp. returned its FitzPatrick 1 plant to full power after workers replaced a transformer, up from 75 percent yesterday. The 852-megawatt unit near Oswego shut Nov. 11 after a transformer failure caused a fire, according to Tammy Holden, a company spokeswoman based at the plant. The cause of the failure is being investigated, she said.
The production increases sent Northeastern output up 3.5 percent to 24,370 megawatts, the highest level since Aug. 12. Generation advanced to 24,717 megawatts in the Southeast as Dominion Resources Inc. raised its Surry 2 reactor to 38 percent of capacity.
Surry 2, which operated at 5 percent of power yesterday, is a 799-megawatt plant in Virginia.
Reactor maintenance shutdowns, usually undertaken in the U.S. spring or fall when energy use is 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.