Solar power satellites are the yin to the yang of Ronald Reagan’s 1980s Star Wars fantasy, and almost as old. Scientists for decades have explored the potential of using space-based solar cells to beam power to the Earth.
It’s an idea with very long legs, as they say, but now the Japan Aerospace Exploration Agency (JAXA) has gone beyond whimsy by actually signing up several major collaborators to launch a giant one-gigawatt space solar power satellite into space. The players are huge – Fujitsu, Mitsubishi Electric and Sharp – and the bucks that JAXA has indicated it will invest in the project are also huge, $21 billion worth of huge.
The plan, according to various recent news reports including London’s Telegraph, is to have the test version of the Space Solar Power System launched in 2020. The final system would go operational in 2030. The station would send down power by laser or microwave.
JAXA would build a mile-wide array of photovoltaic cells similar to the solar panels used on Earth and place them in a geostationary orbit. The beauty of the deal – even though the complexities and obstacles are admittedly huge – is that solar rays are at least five times as powerful in space as they are at ground level, meaning the panels will gather vast amount of energy. In addition the solar arrays can collect energy around the clock regardless of the weather on the ground.
A recent report by researchers at Mitsubishi Heavy Industries said: “Since solar power is a clean and inexhaustible energy source, we believe that this system will be able to help solve the problems of energy shortage and global warming.” Receiver dishes for the substations would probably be located at sea or in the middle of reservoirs, JAXA says. The ground receiving stations would measure nearly two miles across and would produce enough electricity to power about 500,000 homes.
Tatsuhito Fujita, a JAXA researcher, says that in the next few years “a satellite designed to test the transmission by microwave should be put into low orbit with a Japanese rocket.” There are technical challenges to overcome, according to a 2008 JAXA report, including the development of a low-cost and powerful space transportation system; the design of a lightweight solar power satellite; allocating the frequency for SSPS energy transmission and dealing with concerns, real or imagined, about potential health and environmental effects.“These technical challenges must be met since the SSPS is a viable alternative energy source of the near future,” the JAXA report says.
If it all goes according to plan, the electricity produced will be six times cheaper than current energy costs in Japan. It’s technologically feasible right now and with JAXA’s money and heavy-hitter players enrolled this could turn into the equivalent of the Apollo space project of the 1960s, except that this time Japan is leading the way for the peaceful use of space for energy production, not the U.S.