Solar powered

"Boeing-Spectrolab has developed a solar cell that can convert almost 41 percent of the sunlight that strikes it into electricity, the latest step in trying to drop the cost of solar power.

Potentially, the solar cell could bring the cost of solar power down to around $3 a watt, after installation costs and other expenses are factored in, over the life of the panel. The new cost information comes from Boeing, whose Spectrolab unit supplies searchlights and solar simulators, and the Department of Energy, which sponsored the project. Current silicon solar cells provide electricity at about $8 a watt, before government rebates. The goal is to bring it to $1 a watt without rebates or incentives.

The cell achieves 40.7 percent efficiency. The Department of Energy has been sponsoring research to find ways to get solar cells past the so-called 40 percent barrier.

Earlier this year, researchers at Lawrence Berkeley National Laboratories reported that cells made of a new type of semiconductor, zinc-manganese-tellurium, combined with a few atoms of oxygen, could convert around 45 percent of sunlight into electricity. That technology, also partly sponsored by the Department of Energy, has been licensed to RoseStreet Labs in Arizona. It remains to be seen whether this material can be made into solar cells economically."