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By Rory Carroll and Nichola Groom
IVANPAH DRY LAKE, Calif./LOS ANGELES, Feb 13 (Reuters) - Oneof the world's largest solar projects, which uses heat from thesun to generate power in California, opened on Thursday but maybe the last of its kind in The Golden State.
Sprawling across 3,500 acres (1,400 hectares) in the Mojavedesert near the California-Nevada border, the $2.2 billionIvanpah solar thermal power plant has more than 300,000 mirrorsthat reflect sunlight onto boilers housed in the top of threetowers, each of which is 150 feet (45 meters) taller than theStatue of Liberty.
The sun heats water inside the towers, creating steam thatmoves turbines and produces enough emissions-free electricity topower 140,000 homes, or about 392-megawatts.
Though Ivanpah is an engineering marvel, experts doubt moreplants like it will be built in California. Other solartechnologies are now far cheaper than solar thermal, federalguarantees for renewable energy projects have dried up, andnatural gas-fired plants are much cheaper to build.
From a distance, the mirrors - known as heliostats - looklike a pristine lake rising from the desert. Ivanpah, about fourtimes larger than New York City's Central Park, can even be seenfrom the International Space Station.
The Ivanpah plant was partially backed by a $1.6 billionloan guarantee from the U.S. Department of Energy, the samecontroversial program that supported failed solar panel makerSolyndra.
The opening of the Ivanpah plant marks a big step in federaland state renewable energy efforts, but government funds forsuch projects under President Barack Obama have been largelytapped out.
That means the private sector must fill the gap at a timewhen building a natural-gas fired power plant costs about $1,000per megawatt, a fraction of the $5,500 per megawatt that Ivanpahcost.
"Our job was to kickstart the demonstration of thesedifferent technologies," Energy Secretary Ernest Moniz said inan interview high up on one of the plant's three towers.
FAST-CHANGING MARKET
The solar market has changed dramatically since Ivanpah wasapproved by California regulators in 2010.
Traditional solar panels, based on photovoltaic technologythat uses the sun's light to generate electricity, haveundergone a massive drop in price in the last few years, leavingsolar thermal far costlier.
Ivanpah developer BrightSource Energy Inc has failed tosecure a permit for any other solar thermal projects inCalifornia in part due to environmental concerns, includingfears that the intense heat and energy around its plants wouldharm or kill desert birds.
Ivanpah is jointly owned by privately-held BrightSource,power plant owner NRG Energy Inc and Google Inc.
Aside from Ivanpah, NRG has invested in two other massive,government-backed solar power plants in the U.S. West, but saidsmaller photovoltaic (PV) solar panel installations are thefuture of the industry as it shifts toward distributedgeneration on rooftops and away from large solar farms.
"There's no doubt that in terms of price competitivenesssolar photovoltaic is cheaper," NRG Chief Executive David Crane."What really gets me excited in the morning is that there are 50million American buildings that should have solar PV on them."
Solar thermal projects like Ivanpah are more likely to cropup overseas in places like India, where land and sun areplentiful and cheap natural gas is not abundant as it is in theUnited States, said Andy Gillespie, project manager for Bechtel,the engineering and construction contractor for Ivanpah.
Late last year, Oakland-based BrightSource said it wouldfocus increasingly on markets outside the United States and inusing its technology for industrial applications like enhancedoil recovery, desalination and augmenting existing fossil fuelpower plants. The market for solar thermal power will reach 30gigawatts globally by 2020, up from 2.5 GW at the end of 2012,BrightSource said at the time.
"We will have failed as a company if the last project webuild is Ivanpah," BrightSource CEO David Ramm said at theplant's opening.
BrightSource is more than 20 percent owned by French powerequipment maker Alstom SA. Other investors includeventure capital firms VantagePoint Capital Partners and DBLInvestors, Goldman Sachs Inc GS.N, Chevron Technology Ventures and BP Ventures.
