UPDATED: Here’s good news for proponents of a solar tech that some thought would never be widely used: The U.S. Department of Energy said Tuesday it’s offering a conditional commitment for a $90.6 million loan guarantee to build a solar power plant in Colorado that will use a hybrid of mirrors and solar cells.
The loan guarantee will help fund the 30 MW Alamosa Solar Generating Project being built by Cogentrix, which plans to use concentrating photovoltaic (CPV) panels from Amonix, a company backed by venture capitalists like Kleiner Perkins. Cogentrix announced a deal to sell electricity from the project to power company Xcel Energy last August.
UPDATE: Alamosa is
the largest, proposed CPV project in the world among the largest proposed CPV projects, and that tells you something about how difficult it has been to promote the use of CPV in power plant development. Many of the utility-scale solar power projects under development these days are more than 100 MW and use conventional solar panels or solar thermal technologies, which rely on mirrors to concentrate the light to heat fluid for producing steam, which then drives turbines to generate electricity. Through its loan guarantee program, the DOE has helped to finance power projects using emerging technologies that have a hard time attracting private investments.
CPV technology is supposed to generate electricity for less than the other more commonly use solar technologies. By concentrating light, a CPV system uses far less solar cells and that is supposed to cut cost. But the price of solar cells for conventional solar panels has dropped more than half in recent years thanks mainly to generous government incentives, primarily in Europe, that boost solar panel installations. Solar panels can go on rooftops while CPV, with its solar panels that are several times larger than conventional ones as well as bulky trackers, are mostly destined for installation on the ground.
The largest CPV project built in the U.S. last year was a 1 MW project by CPV technology developer SolFocus at a community college in California. Last month, Amonix bested that record when it announced a 2 MW project it co-developed and completed with Granite Construction and University of Arizona at the university campus last month. The electricity goes to the local utility, Tucson Electric Power.
Amonix was actually founded in 1989 and carried out some small projects in the U.S. and Europe before lining up money to build a commercial-size factory and headquarters in California in 2008. It also benefited from the federal stimulus funding and received $5.8 million in manufacturing tax credit to help build a factory north of Las Vegas. The company, which got a new CEO, Brian Robertson, in November 2009 and then raised a B round of $129.4 million led by Kleiner Perkins last year, is set to do a ribbon cutting at the new factory on May 17.
Amonix’s technology uses Fresnel lenses to concentrate the sunlight 500 times onto triple-junction solar cells. Each system, with 53-kilowatt (AC) of generation capacity, is made up of 7 giant modules mounted on a dual-axis tracker. Each module measures 10-ft. by 49-ft and contains 36 sets of lenses and receivers; each receiver contains 30 solar cells. Carla Pihowich, vice president of marketing at Amonix, told me last year that the company was using cells with 39 percent efficiency, which leads to 31 percent efficiency for each module and 25 percent efficiency overall for each system.
Completing the Alamosa project also will be a milestone for Cogentrix, which is owned by Goldman Sachs and owns mostly fossil fuel power plants in the U.S. and hydroelectric power plants in Turkey. Cogentrix’s current solar power plant holding consists of a 43 MW solar thermal project built in the 1980s.
Goldman has been criticized for hogging public land in the western U.S. without having submitted firm plans to develop them for solar. A public records review by the Associated Press last fall showed that Goldman’s energy development company had made more development claims for the Bureau of Land Management land in the southwestern U.S. than any other company. BLM’s land leasing system is first-come, first-served and makes it possible for developers to apply and hold onto land.
Photo courtesy of Amonix