The Prius of Power Plants
The California Energy Commission has greenlighted an application to build the U.S.'s first solar-natural gas hybrid power plant in Southern California's High Desert. The plant will be built on a former Air Force Base outside Victorville - about 100 miles northeast of Los Angeles - and would integrate a 50-megawatt solar trough power station into a 500-megawatt natural gas-fired plant. Solar energy would produce 10 percent of the plant's electricity during peak demand times to lower greenhouse gas emissions from the facility, according to the application. The project is being developed by Newport Beach's Inland Energy for the city of Victorville. "We felt there was a direct analogy between the way renewable resources are used and hybrid cars," Inland Energy executive VP Tom Barnett told Green Wombat. "Electric cars have their limitations but hybrids have taken off. We felt same concept applied to a power plant. We have a solar power plant with the reliability of a combined natural gas cycle plant. We set out to figure out how to integrate solar thermal with gas."
The Victorville 2 plant will use solar trough technology. Fields of parabolic mirrors heat oil or another liquid to create steam that drives an electricity-generating turbine. Several solar trough power plants built in the nearby Mojave Desert in the 1980s and '90s by Luz continue to operate. Some of those plants use natural gas to extend their operating time - say, when its cloudy or when the sun begins to set. So why did Inland Energy decide to make solar a relatively small part of its plant rather than the main power producer? Reliability, says Barnett. "We really didn’t like that idea because we wanted the ability to provide a baseload plant." In other words, Victorville 2 will generate power 24/7. While the plant will supply electricity to the local area, it also will connect to the grid operated by Southern California Edison (EIX), the utility that powers Los Angeles. "We have the best solar resources in world located in close proximity to one of world’s largest cites," Barnett notes. "The fact that we’re just over the hill from L.A. makes this a valuable resource."
And building a solar-powered conventional natural gas plant means that that it may qualify for a federal investment tax credit. The solar component will also be attractive to California's investor-owned utilties, which must get 20 percent of their electricty from renewable sources by 2010 and 30 percent by 2030. "We hoped initially that we would have been able to put a much larger solar facility in the overall plant, but we felt 50 megawatts was the optimal ratio," Barnett says, noting it may be possible to eventually expand the size of the solar fields at the plant, set to begin operation in 2010. He sees opportunity to build more hybrid plants or retrofit existing plants that supply power to PG&E (PCG), San Diego Gas & Electric (SRE) and other utilities. "There's a land rush on for solar," he says. "Everyone's looking at this."