It's taking a while, though -- it's 93 million miles away, after all.

One of the main renewable energy sources, as you probably know, is solar power. We were surprised to find out that it's not so new. Back in the late 1890s, a third of the houses in Pasadena, California used solar water heaters. One of the biggest state-run solar power plants in California was built twenty years ago, in response to the energy crisis of the 1970s. It's called Kramer Junction, and it's in the Mojave desert.

Those facts and a lot more -- who's using solar power now, where in the world it's being used to generate power, and how it's being handled and developed scientifically, politically, through engineering and business -- are all covered by the PBS science program Nova's "Saved By The Sun." It originally aired in April, but this blog didn't see it then, and it just reran last night (at least, it did on Seattle's PBS affiliate, KCTS).

Best of all, of course, is that thanks to the Internets, it's available whenever it's convenient for you.

Right here.