U.S. Northeast Nuclear Output Surges on Maryland Reactor

Nuclear-power generation climbed the most in nearly three months in the U.S. Northeast as Constellation Energy Group Inc. boosted power at two reactors at the Calvert Cliffs site in Maryland.

Nationwide production rose 0.9 percent to 80,016 megawatts, or 78 percent of capacity, a second consecutive advance, according to U.S. Nuclear Regulatory Commission data compiled by Bloomberg. Output was 4.9 percent less than a year ago with 20 of 104 reactors offline.

Constellation’s 862-megawatt Calvert Cliffs 2 reactor returned to full power early today, after operating at 30 percent yesterday. The reactor automatically shut May 8 for unknown reasons, according to Kory Raftery, a plant spokesman.

The 873-megawatt Calvert Cliffs 1 unit also returned to 100 percent of capacity from 96 percent yesterday. The Calvert Cliffs nuclear site is located about 38 miles (61 kilometers) south of Annapolis, Maryland.

The two reactors increased Northeastern nuclear generation by 3.5 percent to 18,926 megawatts, according to commission data compiled by Bloomberg. That’s the biggest gain since Feb. 17.

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.

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