Abengoa (MCE:ABG) announced yesterday that it has begun commercial operation of its PS20 solar power tower. Situated near Seville, Spain, the 20 megawatt project is now the world's largest solar power tower plant in operation - generating enough power for 10,000 homes.

Abengoa's solar power tower is about half the height of the Chrysler building, and is covered with nearly 1,300 mirrored heliostats. These heliostats focus solar radiation which boil water. The boiled water then drives the turbine.

Similar solar power towers are expected to be developed in the U.S. Back in February, Southern California Edison announced a contract to purchase up to 1,300 megawatts of electricity from solar towers built by BrightSource Energy. Regulatory approval and financing is still in the works, but if this thing pans out, the first project will be a 100 MW plant in Ivanpah, CA. Potentially going online in 2013, the system would generate enough power for 65,000 homes

Of course, the BrightSource project isn't without controversy. Environmentalists are concerned that the removal of vegetation on the proposed site will make it difficult for desert tortoises to find shade in the desert heat. And while the company may have to move the tortoises to a similar habitiat, biologists worry about the safety of the tortoises. The last time 670 tortoises had to be moved, 90 died. Apparently these tortoises are not migratory. So if you take them away from their homes, they instinctually start walking back. And this makes them easier prey for coyotes and cars.

Still, I suspect there's more political will behind getting the site developed than there is to save a tortoise. I'm not making any judgments, by the way - just making an observation.

Jeff