U.S. Nuclear Output to Five-Day Low on Xcel Energy Losses

U.S. nuclear-power generation fell to the lowest in five days as Xcel Energy Inc.’s Prairie Island reactor produced less power in the Midwest.

Nationwide production decreased 0.1 percent to 92,438 megawatts, or 91 percent of capacity, according to U.S. Nuclear Regulatory Commission data compiled by Bloomberg. Output was down 0.9 percent from a year earlier, with eight of 104 reactors offline.

Prairie Island 2, a 545-megawatt plant, dropped to 40 percent power from full capacity yesterday. The unit, about 28 miles (45 kilometers) southeast of Minneapolis, was powered down for scheduled maintenance, said Thomas Hoen, a company spokesman based near the plant.

“It is scheduled to be returned to full power in the next couple of days,” Hoen said by e-mail.

The decline led production down for a second day in the Midwest, known by the commission as Region 3, the biggest daily drop in a month.

Generation in the Northeast rose after Entergy Corp. restored its Pilgrim 1 reactor, near Boston, to 50 percent capacity. The plant was manually shut a week ago when its recirculation pumps stopped operating.

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.

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