Space

Japan takes a step towards beaming solar power to Earth from space

Japan takes a step towards beaming solar power to Earth from space
The ultimate goal of the project is to relay power from orbit thousands of miles above Earth (Image: Shutterstock)
The ultimate goal of the project is to relay power from orbit thousands of miles above Earth (Image: Shutterstock)
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The ultimate goal of the project is to relay power from orbit thousands of miles above Earth (Image: Shutterstock)
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The ultimate goal of the project is to relay power from orbit thousands of miles above Earth (Image: Shutterstock)
A rendering of an orbiting solar farm (Image: Japan Space Systems)
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A rendering of an orbiting solar farm (Image: Japan Space Systems)
The final product will receive power from space on a small island (Image: Japan Space Systems)
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The final product will receive power from space on a small island (Image: Japan Space Systems)
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A successful ground test of a system designed to ultimately collect solar power from orbit and beam it back down to Earth was announced in Japan this week by Mitsubishi Heavy Industries. The wireless power demonstration saw 10 kilowatts sent over microwaves from a transmitting unit to a receiver 500 meters (1,640 ft) away.

Mitsubishi says the reception of the power sent through the air was confirmed through the illumination of lights using part of the power transmitted. The company did not confirm what percentage of the power sent actually made it to the receiver, however, which is a key question as the ultimate goal is to relay power from orbit thousands of miles above Earth.

Previous tests of the technology yielded only a tiny fraction of the power sent from one Hawaiian island to another.

No one is expecting a huge orbiting solar farm and corresponding massive microwave power beam to be ready overnight, of course. Mitsubishi says that the successful test conducted at the company's Kobe Shipyard and Machinery Works has verified the viability of the concept, and that the transmission distance and power load mark new milestones for the technology.

Perhaps just as important, the testing confirmed the performance of the control system that will regulate the microwave beam itself. This is a big deal, because if the proposed microwave connection between an orbiting power station and large receiver units on a man-made island in Tokyo Bay were ever fired up at full power, it would be strong enough that workers would need to wear protective clothing – not the kind of thing you'd want to zap 100,000 people wandering through Shinjuku with by accident.

The final product will receive power from space on a small island (Image: Japan Space Systems)
The final product will receive power from space on a small island (Image: Japan Space Systems)

The testing was conducted with Japan Space Systems, a quasi-governmental non-profit carrying out the solar power wireless transmission project.

While successfully beaming power from the sun to Earth via an orbiting system of collectors at a large scale may be decades away, cost billions of dollars and require the invention of some new technologies, the investment can be justified for a country like Japan with limited natural resources, that's still reeling from the Fukushima nuclear disaster.

Mitsubishi also sees less ambitious applications for the technology, like wirelessly powering electric vehicles on Japan's roads.

For full details on how Japan hopes to harvest the sun's energy from space, see our earlier coverage.

Source: Mitsubishi

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6 comments
6 comments
Harap White
so the James Bond move - Die another day was not too far from reality :)
Thomas Lewis
Great technology,we will have to test the environmental impact of high power density microwave beams on different atmospheric layers,but I'm sure we can find solutions.Anything is better than another 100 years of fossil fuels.
christopher
@Thomas - 7+billion people will stop using fossil fuels only when it runs out my man. Nothing's going to change that inevitability, no matter how much anyone wishes it were possible.
Robert in Vancouver
Beaming power down to earth from solar collectors in space would be the ultimate energy source. Hope it works.
But until we find a reliable, easy to use, plentiful, and low cost replacement for fossil fuels, we should be thankful we have them.
4Freedom
How will this be prevented from being used as a weapon?
Albert Feyen
This has to be one of the stupidest ideas ever conceived! What happens when a passenger airplane strays into the microwave beam? What about birds? But most importantly, how much heat will this beam produce in it's path through the atmosphere? Don't we have enough global warming already?