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Space Japan Power

How Japan Plans To Build Orbital Solar Power Stations 230

the_newsbeagle (2532562) writes "Solar power stations in orbit aren't exactly a new idea — Asimov set one of his stories on such a space station back in 1941. Everyone thinks it's a cool idea to collect solar power 24 hours a day and beam it down to Earth. But what with the expense and difficulty of rocketing up the parts and constructing and operating the stations in orbit, nobody's built one yet. While you probably still shouldn't hold your breath, it's interesting to learn that Japan's space agency has spec'd out such a solar power station."
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How Japan Plans To Build Orbital Solar Power Stations

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  • by sandbagger ( 654585 ) on Friday April 25, 2014 @12:54PM (#46842177)

    Seriously, this is right out of a James Bond story. What amazing times we live in.

  • by Maury Markowitz ( 452832 ) on Friday April 25, 2014 @01:09PM (#46842359) Homepage

    > why not just collect it from the ground in the first place?


    > What's going to make collecting energy on the ground from a satellite more efficient than collecting it from the sun?

    In theory you don't have night, so you get twice as much hours of sunlight. Add "cosine error" and the lack of weather, and you're up to five times.

    But then you have to throw away half on the way down to the earth. And then the panels last half as long in space. So in the end it's a *very* small *theoretical* advantage.

    Which is, of course, utterly wiped out by the cost of launch. And everyone knows this. But the guys proposing these things are not power companies, but space companies. As is the case here, it's JAXA, the Japanese space agency. Everyone outside the space field is completely aware of the fact that this is an utterly ridiculous idea.

  • by alexander_686 ( 957440 ) on Friday April 25, 2014 @01:10PM (#46842371)

    2 reasons.

    First, you don’t have to worry about your power going out at night. These things are so far away that the earth’s shadow will rarely fall on the array.

    Second, in theory cells in space should be more efficient then cells buried underneath the atmosphere. I am not sure if they can overcome the practical problems to make it actually more efficient.

    Side note – the US military is also looking at this. Beaming power to remote locations could be more efficient then hauling fuel. Power could be beamed to drones, giving them unlimited endurance.

  • by MetricT ( 128876 ) on Friday April 25, 2014 @02:21PM (#46843073)

    It's not a completely stupid idea, just a mostly stupid idea.

    But it might make financial sense for powering McMurdo Base, for instance. The cost of hauling diesel down there is almost as ludicrous. Remote outposts and stuff.

    Or if your government decided to send a small team of special forces into hostile territory, that would be a convenient way to provide them power. And you could use "cheap solar power for everyone" as good cover for launching something.

  • by Teancum ( 67324 ) <robert_horning@netzero. n e t> on Friday April 25, 2014 @04:42PM (#46844219) Homepage Journal

    The cost of sending 10 metric tons to LEO and about 5 metric tons to GEO is claimed by SpaceX to be slightly under $60 million USD, or about $6k/kg. That seems to be at least a competitive price (few companies say they can beat SpaceX on launch costs). From this figure, sending 10000 metric tons to GEO would be something like $120 Billion. Some cost savings could definitely happen, although the reusable Falcon 9 with all parts being reused on multiple flights is still about $7 billion each, or dropping that price down to about $14 Billion.

    Regardless, a guy who knows the figures for the solar power industry, Elon Musk, who also happens to own a spacecraft launching company as well as a completely separate solar panel manufacturing company (in the form of Solar City) has repeatedly said that spaced based solar power for terrestrial consumers makes absolutely no sense and is something he refuses to become involved with because he thinks it will be a financial disaster if anybody tries to get one going.

I've finally learned what "upward compatible" means. It means we get to keep all our old mistakes. -- Dennie van Tassel