San Onofre State Beach, California, April 2, 2011 - A view of the San Onofre Nuclear Generating Station, one of two active nuclear facilities in California, both of which are located on the coast. The 84-acre generating station, which straddles San Diego and Orange Counties, was built to withstand up to a magnitude 7.0 earthquake according to a spokesman Southern California Edison, the facility's principal owner. The quake in Japan last month was a magnitude 8.9. Even so, seismologists say it is unlikely a quake of this magnitude will hit near San Onofre. Locals refer to the twin domed shells as 'The Boobs'. There were originally three units, but one was decommissioned in 1992. Unlike most nuclear plants, San Onofre uses seawater for cooling, which is why they are missing the large iconic cooling towers that are associated with nuclear reactors. Annual energy output at the plant is the equivalent of that produced by 20 million to 25 million barrels of oil, Southern California Edison officials say. The plant generates 2,200 megawatts of electricity, about 20% of Southern California's usage, or enough to power 1.4 million homes.