Mitsubishi and IHI Corp. said they will join a $21 billion Japanese project to build a massive solar-powered generator in space within 30 years and beam electricity to earth.
Researchers representing 16 companies will spend four years developing technology to send electricity without cables in the form of microwaves, according to an official statement by the Japan’s trade ministry.
In space, the station will be able to generate power regardless of weather conditions.
The effort is to reduce reliance on fossil fuels and take advantage of the most reliable energy source in the solar system: the Sun.
Japan is developing technology for a 1-gigawatt solar station fitted with roughly 2.5 square miles of solar panels, enough to supply about 294,000 Tokyo homes.
The team hopes to have it running in three decades, according to the trade ministry.
The challenge for the team is to figure out how to transport panels to the solar station 36,000 kilometers above the earth’s surface in a cost-efficient way. Otherwise, the station won’t be commercially viable.
Right now, the project is expected to cost 2 trillion yen, or about $21.5 billion USD. It costs approximately $107,000 USD just to launch a single rocket, according to a deputy director at the ministry quoted in the article.
In the U.S., NASA and the energy department have spent $80 million over three decades in an effort to study solar generation in space, according to a 2007 report by the U.S. National Security Space Office.
Japan’s plan is to launch a small satellite fitted with solar panels in 2015, and test beaming the electricity from space through the ionosphere, the outermost layer of the earth’s atmosphere, according to the trade ministry document.
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