San Onofre Nuclear Generating Station workers at 8:36 p.m. Monday cut the flow of power from one of the two reactors at the plant in preparation for planned maintenance and re-fueling.
Plant officials announced plans for the shutdown late last year. About 1,700 temporary workers will replace the massive steam turbine that directly generates Unit 2's 1,100 megawatts of power, and the reactor head. This large component uses step motors to move rods up and down among nuclear fuel in the reactor, creating heat to make steam.
to replace steam generators at the plant here.
Southern California Edison officials never announce ahead of time the exact date of a planned outage.
Some 19 percent of Edison customers get electricity from the plant, according to a company release -- 1,100 megawatts, half the plant's capacity, can power roughly 660,000 homes at any given time. Because each reactor at the plant generates so much electricity, announcing shutdowns ahead of time would give electricity wholesalers who replace the missing wattage the ability to jack up prices artificially during the shutdown.
San Onofre will shut down its Unit 3 reactor for identical upgrades in the fall. The new turbines are expected to increase the plant's output by a total of three percent.