You can't cast a stone without hitting a story on Spain's influential solar sector, and this week is no exception.
Spain-based Abengoa announced it had started operations at the world's largest "solar power tower" – a 20 MW, concentrating solar plant (CSP) near Seville.
The massive installation is called PS20, and its technology is one to watch. In fact, that power tower you see here could be the future of utility-scale solar. Here's how it works:
Over 1,200 movable mirrors, or heliostats, spread over hundreds of acres of desert land, reflecting sunlight onto a receiver at the top of a central, liquid-filled, 531-foot tower. Concentrated rays heat the water, creating steam to drive a turbine that produces power for 10,000 households.
The PS20 is Abengoa's second go at bringing a solar tower online. The first – the 11-MW PS10 – was fired up to great fanfare in 2007. It sits some 15 miles west of Seville and powers 5,500 homes.
But the PS20 represents "a qualitative leap forward" in power tower technology, said Abengoa CEO Santiago Seage. The plant has a higher-efficiency receiver and a better thermal energy storage system than the PS10, among various other improvements in the control and operational systems. An even better version, the AZ20, is in the works, according to the company website.
All three towers will eventually form part of Spain's mega solar project, the Solúcar solar platform. The solar park will generate 300 MW from a variety of sources when it comes online in 2013, with 15 percent coming from tower technology.
Power towers are considered the next in line for CSP glory. Mirrored parabolic troughs remain the classic CSP tech, and today's market standard. Spain happens to be a world leader in both – thanks to a favorable feed-in tariff for CSP development.
As we speak, enterprising Spanish firms, Abengoa, Acciona and now Albiasa Solar, are exporting their trough expertise to the American Southwest and parts of North Africa – not power towers though, at least not yet.
The technology is still at "medium maturity," says Abengoa. Interestingly, it's decades old.
The U.S. was the first nation in the world to test out solar towers in the 1980s. The DOE's first pilot project, the 10 MW Solar One, was operational in California's Mojave Desert from 1982-1986. In 1995, it was restored and renamed Solar Two. The plant was officially decommissioned four years later, for good.
Currently, Israel-based startup BrightSource Energy (whose founder was the head of the now-defunct Luz International, the firm behind California's first trough CSP plants in the 1980s) has plans to return the solar tower to its U.S. desert roots.
In February, the company signed a massive contract with utility Southern California Edison to sell power from seven solar towers in the Mojave Desert. The plants will have a capacity of 1,300 MW. The first, a 100 MW power tower, will be part of the Ivanpah Solar Complex. It is expected to go online in 2013.
Pasadena-based (and Google-backed) eSolar is another upstart to keep a close eye on. The company is constructing an 105-MW facility, the Gaskell Sun Tower, in Kern County, California. Is is slated to be America's very first commercial power tower.
All in all, Spain's solar sector isn't alone trying to master solar tower technology and corner the potentially explosive market. Abengoa certainly has had a head start, but some formidable opponents aren't too far behind.