* Firm says 500 MW project suspended
* Regulators have said facility would impact environment
LOS ANGELES, April 3 (Reuters) - U.S. BrightSource EnergyInc has shelved a major solar power project in California, itssecond such move this year.
The solar plant developer said in a document filed with theCalifornia Energy Commission on Wednesday that it was suspendingits application for permission to build the 500 megawatt HiddenHills solar thermal power project until further notice.
It added in an emailed statement that it had agreed withPacific Gas and Electric to terminate the utility's plan topurchase power from the plant due to "challenges associated withthe project schedule and uncertainty around the timing oftransmission upgrades".
Late last year, CEC staff said the Hidden Hills facilitywould have "significant" impact on the environment, adding thatthe use of photovoltaic solar panels "would be environmentallysuperior" to BrightSource's solar thermal technology.
BrightSource disputed those claims at recent hearings, andthe CEC was expected to issue a final decision on thedevelopment later this year.
BrightSource, based in Oakland, California, said it wouldcontinue to evaluate the project, which was to be located inInyo County near the Nevada border.
In January, BrightSource suspended its 500 MW Rio Mesaproject in Riverside County, California, after multiple delaysin the permitting process.
The company, which canceled a planned initial publicoffering last year, said Hidden Hills remains "a valuable site"but that it would focus on its 500 MW Palen project in themeantime.
In March, BrightSource said Spain's Abengoa wouldbecome a partner in that project, expected to begin constructionat the end of 2013 and to come online in 2016. It is stillwaiting for regulatory approval.
BrightSource is more than 20 percent owned by French powerequipment maker Alstom SA. Other investors includeVantagePoint Capital Partners, DBL Investors, Goldman Sachs Inc, Chevron Technology Ventures and BP Ventures.