Google is converting its renowned headquarters to run partly on solar power, hoping to set an example for corporate America. The Internet search leader announced what is believed to be the largest solar project undertaken by a U.S. company during a solar energy conference in Silicon Valley on Monday. Google believes the sun eventually can deliver as much as 30 percent of the power at its 1-million-square-foot campus in Mountain View–a suburb about 35 miles south of San Francisco.