Developers are beating manufacturers in the U.S. solar power market.

In August, two U.S. companies -- Evergreen Solar Inc. (ESLRQ) and startup Spectrawatt Inc. -- filed for bankruptcy protection. A third company, Germany- based Solon SE (SOO1.XE), announced it would shut down its Arizona solar-panel factory.

The U.S. market for installing solar panels, however, has never been better. Many analysts are predicting that U.S. shipments of solar photovoltaic modules, which convert sunlight into electricity, will double this year to about 2,000 megawatts.

Federal and state subsidies that offset the price of installation, and renewable energy requirements in California, New Jersey and other states are driving the market. A recent steep slide in solar-panel prices, brought on by soft demand in Europe and an oversupply from China, has made solar panels more competitive against conventional power and other renewables, such as solar- thermal, wind and geothermal power.

Despite growing installations, manufacturers are feeling a pinch. Prices have fallen faster than many manufacturers have cut costs, and smaller manufacturers in expensive countries feel the pain more than larger companies operating in China and other low-cost countries.

"You can't make any money manufacturing in the U.S. because you can't compete, " said Paula Mints, a solar market analyst at Navigant Consulting.

U.S. solar-panel makers supplied about 6% of global demand in 2010. That figure is likely to decline this year, Mints predicted.

Solon decided to shut down its U.S. factory before the recent price slide because large, low-priced Chinese manufacturers had scaled up production, said Ed Wegener, vice president of Solon's U.S. operations.

"For us to think we could make what is essentially a commodity product, versus big Chinese players, that didn't make sense," Wegener said in an interview. "We recognized the reality earlier than some people have."

Solon still operates three factories in Europe. In the U.S., the company will sell its European panels and build projects using some of its own panels and some made by Asian rivals.

As part of a plan to boost U.S. renewable-energy generation and create jobs, the Obama administration has provided nearly $1.6 billion in loan guarantees to solar manufacturers and $14.3 billion in loan guarantees to solar power-plant developers.

U.S.-based First Solar Inc. (FSLR), one of the world's largest manufacturers and developers, is getting more than $5.3 billion in loan guarantees to build four large solar farms. The company has a solar-panel factory in Ohio, but makes most of its products in Malaysia. First Solar didn't seek a loan guarantee for a second U.S. factory it is building. Company executives have suggested the U.S. can best support manufacturing by creating long-term financial incentives and a national renewable-energy requirement.

While solar-panel manufacturing is likely to continue migrating to China and other Asian countries, U.S. companies do supply many of the Chinese manufacturing giants. U.S.-based MEMC Electronic Materials Inc. (WFR) and Hemlock Semiconductor supply the raw silicon needed to make solar wafers, while Applied Materials Inc. (AMAT) makes solar-product manufacturing equipment.

The value of such exports exceeded the value of solar panels imported in 2010 by one-half, or almost $2 billion, according to a study by GTM Research and the U.S. Solar Energy Industries Association.

"There's certainly the trend of Chinese manufacturers gaining share in the U.S.," Shayle Kann, a GTM researcher and author of the report, said in an interview. "At the same time, we still have these large incumbent polysilicon and equipment manufacturers, still manufacturing in the U.S. and selling to China."