Japan Researching Solar Power from Space

Heavenly Power Japan is building satellites that will convert solar energy into microwaves and beam them back to Earth. Paul Wootton

http://www.popsci.com/environment/article/2008-06/10-audacious-ideas-save-planet

Beaming Electricity from Space

The Vision Launch giant solar panels into orbit and send limitless clean energy back to Earth

The Plan By 2030, Japan hopes to pull its power from the heavens instead of from polluting coal plants. The idea is to send satellites into geostationary orbit above the equator, where they will unfurl 1.5-mile-long solar arrays and soak up the sun 24 hours a day. Transmitters mounted on the satellites would convert the solar energy into microwave energy and beam it down to terrestrial receiving stations. Equipped with massive antennas measuring two miles across, each station would produce one gigawatt of electricity—enough to power 500,000 homes. That’s twice as much as a typical coal-fired plant, and without any of the greenhouse emissions.

Putting solar panels in space has one obvious advantage: It’s never cloudy 22,000 miles up. On average, there’s 8 to 10 times as much sunlight available in space as there is on Earth, where atmosphere and weather get in the way. Now, with satellite launch costs dropping (about five thousand dollars per pound today, versus $12,000 per pound a decade ago) and energy bills rising (already double what they were in 2005), researchers are finally warming to the idea.

Later this year, in fact, the Japan Aerospace Exploration Agency (JAXA) plans to test the idea on the ground, blasting a microwave beam some 170 feet to a 6.5-foot-wide rectenna, a type of receiver that converts microwaves into DC electricity. Not as glamorous as beaming rays from space, but it’s a vital first step.

Potential Uh-Ohs One frightful but improbable scenario is that the microwave beam misses the receiving antenna and fries something on Earth’s surface. Like a village. To mitigate that risk, JAXA scientists are developing an automated detection system that turns off the microwave beam if the satellite drifts out of line.

ETA JAXA aims to launch its first energy-beaming satellite into orbit by 2013, with a network of powersats that feed energy directly into the grid to follow by 2030.
—Rena Marie Pacella

I think this is an area of alternative energy that should be researched further. If the "Potential Uh-Ohs" can be ironed out, I think this would be a very effective power source. Japan is a leading nation as far as technology goes and if they can figure this out, it would be very successful.