Nuclear Output Climbs as Entergy Boosts Power at Pilgrim

U.S. nuclear-power generation rose as Entergy Corp. began to restore service at its Pilgrim 1 reactor in Massachusetts.

Production increased 0.4 percent to 91,370 megawatts, or 90 percent of capacity, the first gain in three days, according to U.S. Nuclear Regulatory Commission data compiled by Bloomberg. Output dropped 3.2 percent from a year ago, with nine of 104 reactors shut.

The 685-megawatt Pilgrim 1, about 38 miles (61 kilometers) southeast of Boston, was at 17 percent of capacity early today. The unit was shut three days ago after a valve leak, according to a filing with the commission. The boost reversed a two-day drop in nuclear production in the Northeast.

Production in the Southeast climbed for a second day as Southern Co. increased the Hatch 1 unit to 98 percent capacity from 64 percent yesterday. The 876-megawatt reactor, about 20 miles south of Vidalia, Georgia, slowed four days ago because of an electrical malfunction in the plant’s recirculation system, said Matt Williams, a company spokesman based in Birmingham.

“The condition has stabilized and we are ramping up to full power,” Williams said by telephone.

Production reached its lowest level for this time of year since 2005. The last time more reactors were shut on Jan. 23 was 1999, when 11 were offline, according to the commission.

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.