World's Largest Solar Thermal Project Gets a Green Light

The Mojave's expanses will soon be sporting parabolic troughs to soak up the heat. (©

Solar energy, long the linchpin of microgrids and home-energy production, is about to scale up big. In the past three weeks, the California Energy Commission has licensed solar projects with planned energy outputs totaling 1,500 megawatts annually. The biggest of these plants, the Blythe Solar Power Project, got its approval just this week. When the four-part project in the Mojave Desert is complete, it's expected to produce 1,000 megawatts of energy -- a stat that would make it the biggest solar producer in the world.

For a little comparison, only 481 megawatts of new solar capacity were installed in the United States last year. And right now, the very biggest plants produce only 200-350 megawatts, according to the Solar Energy Industries Association and Reuters.

Still, Blythe has a pretty enormous to-do list before it breaks ground -- preferably before year's end if it's going to cash in on stimulus tax incentives. The plant has to secure its funding, its DOE loan guarantee and, since it will be built on federal land, its approval from the U.S. Bureau of Land Management.

That last point raises a few red flags for some folks. Covering 9.3 miles in parabolic troughs poses an obvious threat to wildlife (in this case, the endangered desert tortoise). But there's also the risk of using up too much of an already scarce desert resource: water. Parabolic troughs, like the kind that will power the Blythe plant, usually use water to help turn heat into actually electricity. In most cases, the energy from the intensely hot troughs heats up fluid, which produces steam that spins a turbine that powers a generator. According to the California Energy Commission and the New York Times, the plant's developers have worked to address both problems, selecting a less ecologically delicate site, and reducing its water consumption with cooling technology.