The world’s largest power plant using heat from the sun to generate electricity, a planned $6 billion project in California, recently won approval from U.S. Interior Secretary Ken Salazar. Solar Millennium LLC of Oakland, California, agreed to fund conservation measures protecting the desert tortoise and Mojave fringe-toed lizard in return for permission to build the Blythe Solar Power Project on public land, the Interior Department said today. Blythe will use mirrors to concentrate the sun’s energy rather than solar panels that convert light directly into electricity.

“It’s one of those marquee projects that I’m very proud of,” Salazar said in an interview before announcing the sixth and largest solar project for U.S. land this month. “We’ll demonstrate to the world that we can have large-scale solar projects here in the United States and that they are very much a real part of the energy portfolio for the country.” The Natural Resources Defense Council supports the project, most of which is near industrial and agricultural lands appropriate for solar development, the New York-based group said in a statement. NRDC has called on Salazar to develop national guidelines for renewable-energy development on public lands.