California plans space-based solar power

Californians could soon be powering their homes, and no doubt their hot tubs, from a space-based solar electricity program. The plan by the state’s massive energy company PG&E calls for the generation of 200 megawatts over 15 years to be collected by space-based solar arrays and beamed down to earth via radio frequency.

PG&E hopes to have the system running by 2016 and is seeking permission from regulators to contract with a company called Solaren to put the system in place.

Experts say that harnessing solar power in space has advantages over terrestrial systems since solar energy can be harvested around the clock and is never obscured by clouds or bad weather.

Solaren’s solar-power satellite would consist of mirror arrays up to several kilometers wide, which would focus sunlight onto photoelectric cells. The electrical power would be converted into a microwave beam directed towards Earth, where it would be converted back into electricity.

According to the company, the system could generate roughly 1.2 to 4.8 gigawatts of power, at a price comparable to that of other renewable energy sources. “While a system of this scale and exact configuration has not been built, the underlying technology is very mature and is based on communications satellite technology,” Solaren CEO Gary Spirnak said in announcing the move.
“For over 45 years, satellites have collected solar energy in earth orbit via solar cells, and converted it to radio frequency energy for transmissions to earth receive stations,” he said.