An Israeli company will build the world's largest solar energy park in Southern California's Mojave Desert to supply enough electricity to power 400,000 homes in central and northern California. The massive $ 2 billion project was announced on July 25, following the signing of a 25- year contract between Israel's Solel Solar Systems and California's Pacific Gas and Electric public utility. David Saul, the project leader for the Mojave Solar Park, described the venture as " a landmark" and " the largest solar project built to date" in a phone interview during his brief visit to San Francisco. When completed in 2011, following two years of construction, the solar park will stretch over 6,000 acres or ( 23 sq. km.), use 1.2 million mirrors and 317 miles of vacuum tubing to harness the power of the desert sun, and deliver 553 megawatts of clean energy. The American-born Saul, a graduate of the University of California at Berkeley, got his start in Silicon Valley, moved to Israel in 1983, and is now Solel's chief operating officer. He said his company will design and manufacture the components at its plant in Beit Shemesh and will be responsible for the development of the park, in cooperation with a number of American firms. Solel's primary development office will be in Los Angeles. Solel will use its patented solar thermal parabolic trough technology, in which rows of trough- like mirrors heat a special fluid that generates steam, which powers turbines that generate electricity, to be transmitted to PG& E's electric grid. The technology was developed by another Israeli company, Luz, which built nine solar power plants in the Mojave Desert between 1984- 1991. Luz went bankrupt in the early 1990s, due to a denial of tax breaks by the state of California, Luz officials charged at the time. However, the plants are still operational and have been recently upgraded by Solel. As the world's largest solar thermal company, Solel is also building a large solar park in southern Spain. Surprisingly, there are no solar parks on a scale of the Mojave project in Israel, a failure critics blame on bureaucratic roadblocks. However, the government recently announced plans for a solar plant near Dimona. California state agencies must still approve the Mojave Solar Park, but PG&E and Solel spokespeople said they were confident of a go- ahead because of the state's own cleanenergy projections. State regulations mandate that at least 20 percent of electricity provided by public utilities must be based on renewable energy sources, such as solar or wind, by 2010.