For more than 40 years, scientists have dreamed of collecting the sun’s energy in space and beaming it back to Earth. Now, a host of technological advances, coupled with interest from the U.S. military, may be bringing that vision close to reality.
Despite the enormous promise of solar power, the drawbacks of the technology remain significant. People need electricity every day, around the clock, but there’s no part of the United States that is cloud-free 365 days a year — and no solar radiation at night. You have to find some way to store the energy for those sunless periods, and there’s not yet a large-scale way to do that.
Moreover, the best locations for solar arrays — the deserts of the American Southwest — are far from the centers of population, so even under the best of circumstances you’d have to send electricity many hundreds of miles through transmission lines that don’t yet exist.