Solar installations just keep getting bigger and bigger. The latest is today's announcement that PG&E -- in the biggest deal of its kind -- is buying 553 megawatts from a solar plant that's being erected in the Mojave Desert by Solel. But put aside those mental images of acre upon acre of solar panels, this plant will use "solar trough" technology when completed in 2011.

Todd Woody over at Green Wombat explains:

Solel will use a more advanced version of the solar trough for its Mojave project, which will contain 1.2 million mirrors and 317 miles of vacuum tubing.

...Solar trough power plants use parabolic mirrors to track the sun and heat tubes of liquid to produce steam that drives electricity-generating turbines. The efficiency of solar troughs is quite a bit lower than other utility-scale technologies under development, but it's tried and true and that's what apparently attracted PG&E (PCG), which emphasized it was "commercially-proven."

You can catch more details in this post.