Planners of $21bn project admit need to dispel fears of lasers roasting birds and slicing planes

Japan’s space agency says plans for a $21bn out-this-world solar power generator are on track for a full launch by 2030, with hopes that it will produce electricity at a cheaper cost than terrestrial sources.

The Japan Aerospace Exploration Agency (JAXA), which is overseeing the nation’s recently announced plan for a 1GW solar power space station, said the project will utilise an array of photovoltaic dishes spanning several square kilometres that would hover in geostationary orbit outside the Earth’s atmosphere.

The dishes’ solar cells would capture the sun’s energy, which is at least five times stronger in space than on Earth, and beam it down to the ground using clusters of lasers or microwaves. The beams would be collected by parabolic antennae located in restricted areas at sea, or on dam reservoirs, according to JAXA.

The project, dubbed the Space Solar Power System, is expected to produce electricity at eight yen ($0.09) per kilowatt hour – six times cheaper than its current cost in Japan.

The first step would see, within several years, “a satellite designed to test the transmission by microwave… put into low orbit with a Japanese rocket”, JAXA researcher Tatsuhito Fujita told Agence France Presse news agency yesterday.

Around 2020, a large flexible photovoltaic structure with 10MW of capacity would be launched and tested, to be followed by a 250MW prototype. A full launch of the project is targeted for 2030.

The technology would be safe, said JAXA, although it conceded a need to dispel fears among the general public of laser beams roasting birds or slicing aircraft in mid-air.

Several Japanese hi-tech giants are participating in the project through a research group named Institute for Unmanned Space Experiment Free Flyer. They include thin-film photovoltaic module producer Mitsubishi Heavy Industries, solar cell makers Mitsubishi Electric and Sharp, satellite developer NEC, and Fujitsu – which produces power relays tailored for use in solar energy systems.