Japan eyes solar station in space

[citizen k]

Japan eyes solar station in space
by Karyn Poupee

TOKYO (AFP) – It may sound like a sci-fi vision, but Japan's space agency is dead serious: by 2030 it wants to collect solar power in space and zap it down to Earth, using laser beams or microwaves.
The government has just picked a group of companies and a team of researchers tasked with turning the ambitious, multi-billion-dollar dream of unlimited clean energy into reality in coming decades.

With few energy resources of its own and heavily reliant on oil imports, Japan has long been a leader in solar and other renewable energies and this year set ambitious greenhouse gas reduction targets.

But Japan's boldest plan to date is the Space Solar Power System (SSPS), in which arrays of photovoltaic dishes several square kilometres (square miles) in size would hover in geostationary orbit outside the Earth's atmosphere.

"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," researchers at Mitsubishi Heavy Industries, one of the project participants, wrote in a report.

"The sun's rays abound in space."

The solar cells would capture the solar energy, which is at least five times stronger in space than on Earth, and beam it down to the ground through clusters of lasers or microwaves.

These would be collected by gigantic parabolic antennae, likely to be located in restricted areas at sea or on dam reservoirs, said Tadashige Takiya, a spokesman at the Japan Aerospace Exploration Agency (JAXA).

The researchers are targeting a one gigawatt system, equivalent to a medium-sized atomic power plant, that would produce electricity at eight yen (cents) per kilowatt-hour, six times cheaper than its current cost in Japan.

The challenge -- including transporting the components to space -- may appear gigantic, but Japan has been pursuing the project since 1998, with some 130 researchers studying it under JAXA's oversight.

Last month Japan's Economy and Trade Ministry and the Science Ministry took another step toward making the project a reality, by selecting several Japanese high-tech giants as participants in the project.

The consortium, named the Institute for Unmanned Space Experiment Free Flyer, also includes Mitsubishi Electric, NEC, Fujitsu and Sharp.

The project's roadmap outlined several steps that would need to be taken before a full-blown launch in 2030.

Within several years, "a satellite designed to test the transmission by microwave should be put into low orbit with a Japanese rocket," said Tatsuhito Fujita, one of the JAXA researchers heading the project.

The next step, expected around 2020, would be to launch and test a large flexible photovoltaic structure with 10 megawatt power capacity, to be followed by a 250 megawatt prototype.

This would help evaluate the project's financial viability, say officials. The final aim is to produce electricity cheap enough to compete with other alternative energy sources.

JAXA says the transmission technology would be safe but concedes it would have to convince the public, which may harbour images of laser beams shooting down from the sky, roasting birds or slicing up aircraft in mid-air.

According to a 2004 study by JAXA, the words 'laser' and 'microwave' caused the most concern among the 1,000 people questioned.

[Neil]

Solar power is nowhere near inexhaustible.  Somewhere between 5 and 6 billion years from now, the white dwarf Sun won't be able to provide much energy at all.

[Josquius]

How very 1980s sci-fi.
But cool.

[jimmy olsen]

Awesome, but how are they going to protect the stations from Chinese anti-satilite missiles?

I'll tell you how, the Space Battleship Yamato!

[Neil]

Awesome, but how are they going to protect the stations from Chinese anti-satilite missiles?

I'll tell you how, the Space Battleship Yamato!

A space battleship would be unwise.  It would make more sense to announce that any attack on the satellites would be looked upon as an act of war and then put up a bunch of kinetic impactors.

[sbr]

I am sure that people smarter than I have looked into this project but I am curious how launching "arrays of photovoltaic dishes several square kilometres (square miles) in size" into "geostationary orbit outside the Earth's atmosphere" and then shooting the energy back down to earth with "clusters of lasers or microwaves" to "gigantic parabolic antennae" would be either more efficient or cheaper than putting the solar panels here on earth.

[Gaius Marius]

I am sure that people smarter than I have looked into this project but I am curious how launching "arrays of photovoltaic dishes several square kilometres (square miles) in size" into "geostationary orbit outside the Earth's atmosphere" and then shooting the energy back down to earth with "clusters of lasers or microwaves" to "gigantic parabolic antennae" would be either more efficient or cheaper than putting the solar panels here on earth.

There is presumably no NIMBYism in space, which they might get trying to locate these solar panels on some part of Japan.  So this project might well proceed faster, less legal costs, etc.

[The Larch]

Unrealistic and ridiculous. Solar energy still has a lot to grow and to prove already in the surface before getting into nutty anime-like projects like this with no basis in realistic planning.

[Neil]

I am sure that people smarter than I have looked into this project but I am curious how launching "arrays of photovoltaic dishes several square kilometres (square miles) in size" into "geostationary orbit outside the Earth's atmosphere" and then shooting the energy back down to earth with "clusters of lasers or microwaves" to "gigantic parabolic antennae" would be either more efficient or cheaper than putting the solar panels here on earth.

There is presumably no NIMBYism in space, which they might get trying to locate these solar panels on some part of Japan.  So this project might well proceed faster, less legal costs, etc.

Which is great, but wouldn't cover launch costs.

Do NIMBYs hate solar panels?

[Maximus]

The atmosphere blocks a great deal of solar energy. The idea is that you collect it in space, then beam it down to the surface in a form that penetrates the atmosphere better. Essentially it is a space-saving measure.

[KRonn]

Interesting idea. I've heard of this idea before and it sounds good, but I have no idea if it's actually feasible as far as the energy obtained being worth the cost, or even how reliable such a system would be.

[DontSayBanana]

I'm no engineer, but isn't remote power transmission only feasible over short distances?  Also, I'm pretty sure keeping a laser's cohesion over the distance from geostationary orbit to the surface would take up most of the power gleaned, unless they stuck the receiver on top of Everest or similar.

[Darth Wagtaros]

I'm no engineer, but isn't remote power transmission only feasible over short distances?  Also, I'm pretty sure keeping a laser's cohesion over the distance from geostationary orbit to the surface would take up most of the power gleaned, unless they stuck the receiver on top of Everest or similar.

I think the atmosphere would be the killer.  Shame Hamilcar broke like a little girl and ran away. He'd explain it all.

[Iormlund]

There are two problems with solar power on Earth (other than cost). The first is the atmosphere, which blocks a lot of radiation. The second problem is the night. Duh.

Add the two and you have a huge problem, because you can't rely on solar power for anything. Thus you need to have gas-fueled stations ready to fire when there's not enough sunshine.

Putting the panels in space solves both things. Microwaves can penetrate the atmosphere without losing so much of its power. And you can place the satellites in orbits that allow them to collect energy and beam it down during the night. The result is a no-emissions embargo-proof baseload energy source. Pretty much the Holy Grail.

I don't know how feasible this is. Nobody really knows, which is why I'd love to see the Japanese (or ESA) doing this - NASA seems to be more interested in wasting billions sending men to Mars.

[sbr]

How advanced is the Japanese space program?  I am assuming that this project would require missions with enormous payloads, is that something they could pull off themselves or would they have to rent out a space shuttle?