Photos: Peering into energy's future

There's more than one way to make electricity from sun. At WIREC 2008, there were a handful of companies showing off different designs for solar concentrators.

Concentrators can be used either to generate electricity through heat or concentrate light onto solar cells to maximize their output. Here is a cutout of Power-Spar, a solar concentrator from Menova Energy in Canada. The actual solar concentrator is much longer--about 40 feet--and the installation would include several concentrators mounted on racks.

The Power-Spar can be used for several functions. Light from the concentrator can be reflected on solar cells to make electricity, generate heat for use in buildings, or carry daylight to a building through fiber-optic cabling. The company is marketing these systems to companies as a way to generate power and heat on-site.