OptiSolar Inc., which grabbed headlines last year with plans to build a massive solar power plant in California's Central Valley, has stopped its manufacturing operations and will lay off most of its staff.

Low on funding, the company has been searching for a buyer but hasn't been able to find one, said Alan Bernheimer, OptiSolar's vice president of communications.

In all, 200 employees will lose their jobs: 142 at the company's Hayward headquarters and 58 at a second facility just outside Sacramento. Fewer than 100 employees will remain. The company will continue hunting for a buyer and could resume production of its thin-film solar panels in Hayward if someone purchases the operation, Bernheimer said.

"If we can find a buyer, it's certainly ready to start," he said. "But it's going to take a buyer with resources, cash flow, the ability to invest in research and development."

OptiSolar's experiences reflect the solar industry's recent, stunning change in fortunes.

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Last summer, OptiSolar announced that it would build a solar power plant capable of generating a maximum of 550 megawatts, roughly the same as a midsize fossil fuel power plant. Pacific Gas and Electric Co. agreed to buy the electricity from the plant, to be built in San Luis Obispo County.

But the credit crisis cut off the ability of young, green-tech companies to find funding for their projects. Earlier this month, OptiSolar sold its portfolio of planned but unbuilt power plants to rival First Solar for $400 million in stock. Rather than develop power plants, the company would concentrate on making and selling its ultra-thin solar panels.

But even after the deal with First Solar, OptiSolar couldn't find enough funding to keep its operations running.