U.S. nuclear-power generation declined for the first time in four days after a Maryland reactor shut down because of a pump failure.
Nationwide production fell 0.4 percent to 84,196 megawatts, or 83 percent of capacity, according to Nuclear Regulatory Commission data compiled by Bloomberg. Output was 2.2 percent higher than a year ago with 17 of 104 plants offline.
Constellation Energy Group Inc.’s 862-megawatt Calvert Cliffs 2 reactor, about 38 miles (61 kilometers) south of Annapolis, tripped offline yesterday because of equipment failure associated with the steam generator feed pump, the NRC’s daily event notification report shows.
“We are repairing a coupling that is part of one of our steam generator feed pumps,” Kory Raftery, a spokesman with the company, said in an e-mail today. “Unit 2 will be returned to service once the investigation is completed, repairs are made, and the system is fully tested.”
Raftery declined to provide details about the expected duration of the shutdown.
American Electric Power Co. slowed output at the 1,009-megawatt D.C. Cook 1 reactor in Michigan to 49 percent from 69 percent. The plant, about 26 miles northwest of South Bend, Indiana, had been ramping up after being shut for refueling and planned maintenance.
“We had an issue with the hydraulic fluid for the main feed pump, and if we take one main feed pump out of service we have to be back under 50 percent of power,” Bill Schalk, a spokesman at the Cook plant, said in a telephone interview. “We expect to be back up to full power shortly.”
Northeast and Midwest generation dropped today as the two reactors cut output while the Southeast gained.
NextEra Energy Inc. increased production at the 720-megawatt Turkey Point 3 reactor in Florida to 93 percent of capacity, from 49 percent yesterday. The reactor is located about 20 miles south of Miami.
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 46 days in 2012, according to the Nuclear Energy Institute.