The sun blasts Earth with enough energy in one hour—4.3 x 1020 joules—to provide all of humanity's energy needs for a year (4.1 x 1020 joules), according to physicist Steven Chu, director of Lawrence Berkeley National Laboratory. The question is how to most effectively harness it. Thin-film solar cells may be the answer: One recently converted 19.9 percent of the sunlight that hit it into electricity, surpassing the amount converted into power by mass-produced traditional silicon photovoltaics and offering the potential to unleash this renewable energy source.
saved byEnergy Net on 2008-04-30