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Power Technology

Japan Plans $21B Space Power Plant 550

Mike writes "Japan has announced plans to send a $21 billion solar power generator into space that will be capable of producing one gigawatt of energy, or enough to power 294,000 homes. The project recently received support from Mitsubishi Electric Corp. and IHI Corp, who are now teaming up in the race to develop new technology within four years that can beam electricity back to Earth without the use of cables. Japan hopes to test a small solar satellite decked out with solar panels by the year 2015."
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Japan Plans $21B Space Power Plant

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  • Cue Standard Replies (Score:5, Informative)

    by hardburn ( 141468 ) <hardburn&wumpus-cave,net> on Tuesday September 01, 2009 @02:11PM (#29276225)

    If you are about to post anything about any of the issues below, please at least read the Wiki page on SBSP [wikipedia.org] first. Doing so will save a lot of electrons.

    • How do you beam the power
    • Give people cancer (or other safety issues)
    • Weaponization
    • Beam energy will be lost in transit, absorbed into the atmosphere, and contribute to global warming

    A basic understanding of the technology and physics will debunk all of these, and WikiPedia gives a good overview of these non-criticisms. Anyone continuing to parrot them below will be flogged.

  • by Delwin ( 599872 ) * on Tuesday September 01, 2009 @02:14PM (#29276277)
    The amount of solar energy per m2 outside the Van Allen Belt is far more than what we get here on earth.
  • by onkelonkel ( 560274 ) on Tuesday September 01, 2009 @02:26PM (#29276465)
    What is there left to post? Any science or tech article outside of the IT world is guaranteed to produce an avalanche of specious, ill informed or just plain stupid comments. The best always point out some glaringly obvious non-flaw in the plan "Hurh, hurh, those scientists are so dumb. How are they going to beam solar power on a cloudy day? Bet they never thought of that. They're not so smart..."
  • by Meumeu ( 848638 ) on Tuesday September 01, 2009 @02:33PM (#29276579)

    ...24 hours of sun...

    Maybe my geography or astronomy are off - Feel free to correct/bitch-slap me if I'm confused.

    How does a satellite in geosynchronous orbit get 24-hours/day of sunlight?


    The equator and the ecliptic are not on the same plane, which means the only times when a geosynchronous satellite is in eclipse is around the equinoxes. In the worst case it can last up to 80 minutes of shadow.

  • by jeffb (2.718) ( 1189693 ) on Tuesday September 01, 2009 @02:39PM (#29276661)

    Maybe my geography or astronomy are off - Feel free to correct/bitch-slap me if I'm confused.

    How does a satellite in geosynchronous orbit get 24-hours/day of sunlight?

    Geosync is way out there. If the satellite's orbit were in the same plane as the Earth's, it would only get blocked for about an hour a day. But since geostationary orbit is inclined to Earth's orbit (as Earth's equator is inclined), it only gets blocked at all during two times of the year; the rest of the time, when it's "behind" Earth relative to the Sun, the Sun shines "over" or "under" the Earth and hits it unimpeded.

  • by hardburn ( 141468 ) <hardburn&wumpus-cave,net> on Tuesday September 01, 2009 @02:39PM (#29276665)

    The third point is nothing. The energy in question is not easily absorbed by the human body or anything else that isn't specifically designed to capture microwaves. This no more contributes to space weaponization than any other activity in space.

    Consider yourself flogged.

  • Re:SPP (Score:2, Informative)

    by klingens ( 147173 ) on Tuesday September 01, 2009 @02:41PM (#29276699)

    If you don't find what you see on the picture you've linked impressive, something is wrong with you.

    Of course, that's just a drawing, so it's still just vaporware.

    Yes I'm very much impressed by a screenshot from a game: http://www.egosoft.com/games/x3tc/info_en.php [egosoft.com]

  • Re:seriously? (Score:3, Informative)

    by Anonymous Coward on Tuesday September 01, 2009 @02:45PM (#29276745)

    Current power stations being built with two Westinghouse AP1000 reactors are in the $10 billion range, have an estimated life span around 25 years (versus 15), and produce more than twice as much power. This is a very expensive boondoggle in comparison.

    Over time maybe the costs can come down. I guess you have to build one to figure out the process in any case.

  • by DragonWriter ( 970822 ) on Tuesday September 01, 2009 @02:47PM (#29276765)

    Recession means "lack" of spending behavior, not "lack" of money.

    No, actually, it doesn't mean either. It means an overall decline in economic activity across many dimensions taken together, the nearest thing to a single-dimensional rough definition is a decline in production rather than spending. A decline in spending usually occurs during a recession, but its not the same thing as a recession.

  • Re:seriously? (Score:3, Informative)

    by Maximum Prophet ( 716608 ) on Tuesday September 01, 2009 @02:58PM (#29276899)
    The Japanese have been known to take out 100 year mortgages, so electing a politician with a 50 year plan is not out of the question.
  • Re:seriously? (Score:2, Informative)

    by Scubaraf ( 1146565 ) on Tuesday September 01, 2009 @03:06PM (#29276995)
    Agreed! It comes out to 71K per household!

    I don't know what the average monthly bill is for electricity in Japan, but assuming a measly $200 per month, this thing would have to last 29 years just to break even! And that ignored maintenance costs and likely overruns!

    If it works, it's a great proof of concept - and something you can sell to other nations once the costs come down.
  • by Tekfactory ( 937086 ) on Tuesday September 01, 2009 @03:10PM (#29277027) Homepage

    Just so we're clear

    SpaceX has published launch costs for the Falcon 9 Heavy @ $2,726 per pound, and Elon Musk testified before congress that they have plans to get costs down to $500 per pound.

  • by hardburn ( 141468 ) <hardburn&wumpus-cave,net> on Tuesday September 01, 2009 @03:14PM (#29277053)

    No, it really isn't, not at the frequencies useful for SBSP. These frequencies must be specifically choosen to cut through all the water in the atmosphere (along with anything else). Since human bodies are mostly water, you're not going to absorb very much of the stuff, and what stuff you do absorb will be no different from being on the beach on a sunny day.

    If the military wants to weaponize the basic technology, they're going to have to design with it specifically in mind (even if it's possible to use microwaves for this purpose, which it probably isn't). They won't get a useful weapon using the civilian power system. The civilian system might help increase launch capacity and thus make the weapon system cheaper to build, but again, that's no different from any other space activity of this magnitude.

  • by hardburn ( 141468 ) <hardburn&wumpus-cave,net> on Tuesday September 01, 2009 @03:17PM (#29277089)

    I'm sure there is no possible way the power transmission system could be changed to emit wavelenths to do something like destroy an ICBM or cause problems with a communication/power infrastructure on earth.

    Your sarcasm is actually true. The antennas involved need to be tweaked to a specific frequency for maximum efficiency. If the military wants to do this, they'll need to build their own stuff, which they'd do anyway if they cared to.

  • by mollog ( 841386 ) on Tuesday September 01, 2009 @03:21PM (#29277135)
    "I honestly don't know what the heck is going on in the US!"

    If you just woke up from a coma, America went through 8 years of voodoo economics, record deficit spending by a runaway congress, a jobless recovery, and an economy propped up with record low interest rates that lead to a housing bubble. Combine that with a failure to monitor the largest financial institutions because of an ideological aversion to regulation, and you have a perfect financial storm.

    Meanwhile, Americas's financial frenemies are exploiting an arbitrage on labor and environmental costs, along with currency manipulation and protectionism, to supercharge their economies.

    Now that you're up to date, we have a new American President who is not beholden to special interests, especially energy interests, who has some vision for a clean energy future. Japan has just announced a bold new project to generate photovoltaic energy and some Americans are very curious.

    All of that was sardonic. What do you not understand?
  • by Bakkster ( 1529253 ) <Bakkster.man @ g m a i l .com> on Tuesday September 01, 2009 @03:24PM (#29277165)

    Recession means "lack" of spending behavior, not "lack" of money. Often spending on promising technologies has important spin-off applications which bolster the economy / people spend money.

    That seems to be the exact opposite problem of what we have in America. We thought we had way more money that we even thought we had. When the magicians disappeared, all the make-believe money that was coursing through the veins of the economy dried up and caused the businesses who were relying on people spending that make-believe money to burn out and fail. It was the lack of money that caused the lack of spending, not the lack of things to buy.

    Nope, it's exactly the problem. The economy was cruising right along while people were (over) spending. The entire reason that the auto industry is in tough times is because people have been reducing their spending and putting off their car purchases. The economy was just fine when we were spending money, the problem was the money was from credit based on overvalued assets (such as houses).

    This also explains why it takes time to get out of a recession. People need to spend money for companies to have the income to hire more employees, who can then buy other more stuff.

  • by Darkness404 ( 1287218 ) on Tuesday September 01, 2009 @04:18PM (#29277707)
    And then you had a media who acted like it was the end of the world and caused some people to stop paying their mortgage. Seriously. I have a friend who is a banker and said that after all the media stories people who were never late on a payment just stopped paying. When they called them to ask why they haven't made a payment they responded by saying "Well my house is going to be foreclosed anyways..." they were shocked to learn that if they paid their loans like they have been paying they could continue living normally.
  • by Anonymous Coward on Tuesday September 01, 2009 @04:25PM (#29277791)

    Yes, we have those around here as well, we call them "retarded". We usually don't give them loans, though.

  • by hardburn ( 141468 ) <hardburn&wumpus-cave,net> on Tuesday September 01, 2009 @04:40PM (#29277953)

    You're assuming the design only has the capability to transmit microwaves.

    Which is a pretty good assumption to make, because transmissions at any other frequency (be it IR or some radio frequency) will require a totally different transmission system. An extra system means extra weight, which would increase launch costs on a system that will already be struggling to be economically competitive with ground-based systems.

    Using this stuff as a weapon makes a good movie, but poor science.

  • by TheRaven64 ( 641858 ) on Tuesday September 01, 2009 @04:49PM (#29278047) Journal

    Japan has just announced a bold new project to generate photovoltaic energy and some Americans are very curious

    In case you weren't paying attention, this follows a similar announcement by the state of California (although I seem to recall their proposal being a bit smaller - in fact it's mentioned in TFA: 200MW, as opposed to 1GW for the Japanese plant). It's a marginally less silly idea when Japan suggests it because they don't really have much landmass that's suitable for solar power generation, but it's still not actually a good idea.

    Once you factor in the energy cost of getting into orbit, it's a silly idea. The lightest solar cells we can produce are 84 mg/cm2. That works out at 840g/m^2. The cheapest flights to orbit cost around $4,300/kg, or $3,612 for a 1m^2 of lightweight solar panel. This panel is hit by about 1kW of sunlight, but the most efficient panels will only output around 400W from this (the lightest are not the most efficient, but we'll gloss over that for now). The highest cost of wholesale electricity I can find is around $1000/MWh, or $1/kWh, or $0.4 for every hour of operation. To recoup just the launch costs, this magical solar cell would have to operate for one year.

    Now, these are best-possible-case figures. In practice, the efficiency is likely to be a shade under 20%, which doubles the ROI time. The launches are probably not all going to be the cheapest possible, and the solar panels aren't the only thing that needs lifting up (you need the frame, the microwave transmitter, and so on). I've also been assuming 100% efficient power transmission to the ground so far. If it's only 50% efficient (which is still pretty high) then double the ROI time again. I also assumed the solar panels themselves were free. Given that the solar wind in orbit is fairly hostile to solar panels, you'd be lucky to get a positive EROI before the panels degraded to such a degree that they were no use.

  • by antirelic ( 1030688 ) on Tuesday September 01, 2009 @06:20PM (#29279079) Journal

    How is that informative? What EXACTLY has Obama changed or plans to change?

    Oh, right. Very different. Record deficit spending: $700 billion stimulus package... which was just a massive pork project for congress. Lets not forget, Ben Bernanke. Didnt Obama JUST reappoint him to the SAME POST as GW Bush?

    Jobless recovery, I believe those were the EXACT same words Obama used to describe our current "recovery" (like we are really in a recovery). Cash for clunkers is responsible spending?!? Exactly how?

    Yeah, Obama is a different bird. His "advisors" are a bunch of Socialists and Communists (Van Jones professed to be one).

    Aversion to regulation. Check. I love this new administration and its wonderful new regulation. Wait till cap-n-tax takes hold. Jobless recovery... lol. Universal health care... even lol'er. Fiscal responsible regulatory regime is not Obama. An economic illiterate with a desire to force dramatic socialist policies without consideration of the reality, check.

    How many articles need to be posted on Slashdot.org about the feasibility of "clean energy resources" replacing carbon based fuels? The math is out there, but dont let physics or science get in the way of "Eco-Religion".

    Bush was a huge asshat who increased the size of government and spent like a drunken sailor. Screw him. But if you are pissed at Bush for his poor policies, how can you turn around and embrace Obama who has already outspent Bush in just 6 months?

    I do agree with your point on our "frenemies".

    See, I'll agree with anyone when there right.

  • by benjamindees ( 441808 ) on Tuesday September 01, 2009 @06:49PM (#29279335) Homepage

    Right... so what might cause an economy to stop producing as much stuff? Might it be... people aren't buying the stuff that gets made? That seems like a pretty basic cause-and-effect relationship to me.

    It is a cause-and-effect relationship, it's just a completely unimportant one. The important thing is not that people aren't buying enough stuff, it's that the stuff being produced sucks ass.

    The Keynesian response is to rob from people who aren't buying enough of the stuff that sucks ass, and give it to the people who do buy the stuff that sucks (and who are not getting enough benefit out of it in order to afford to buy more), in order to prop up the crappy producers who are wasting resources building stuff that sucks.

    The correct, most economical, and most beneficial solution is to stop producing stuff that sucks ass, let the people who produce that stuff go bankrupt so that they will learn never to produce stuff that sucks again, and allocate their capital to producers who will create stuff that doesn't suck and that people with money will buy.

    I'll respond to the rest in a few mins.

  • by Keith Henson ( 1588543 ) * on Wednesday September 02, 2009 @07:24PM (#29293055) Homepage
    Tekfactory put his finger squarely on the problem. $500/pound is about $1000/kg and that is ten times to high for space based solar power to undercut fossil fuels. The Japanese recognize this.

    "Transporting panels to the solar station 36,000 kilometers above the earth's surface will be prohibitively costly, so Japan has to figure out a way to slash expenses to make the solar station commercially viable, said Hiroshi Yoshida, Chief Executive Officer of Excalibur KK, a Tokyo-based space and defense-policy consulting company. "These expenses need to be lowered to a hundredth of current estimates," Yoshida said by phone from Tokyo.

    I get the same number close enough. Current price to GEO $20,000/kg; required for space based solar power to displace fossils by being substantially less expensive (1-2 cents per kWh) is $100/kg, a factor of 200.

    So design to cost. Start with the rocket equation:

    Needed 100 t/hr to GEO, $100/kg. Try a two stage to GEO. Requires 14 km/sec, get the first 4 km/sec with a mass ratio 3 hydrogen/oxygen rocket. 4km/sec is easy to do, ask Elon Musk. To get the remaining 10 km/sec with a mass ratio 2 means an average exhaust velocity of 15km/sec.

    Because you stage far short of LEO, the second stage must have relatively high thrust so 60 km/sec exhaust velocity ion engines won't do. Ablation laser propulsion (well understood physics) with an average exhaust velocity of 15 km/sec will provide over a g at 4 GW. The suborbital path keeps the second stage out of the atmosphere long enough (15 minutes) for the laser to push the second stage into geosynchronous transfer orbit.

    At 4 payloads an hour (working the laser full time), each payload to GEO needs to be 25 t. So the laser stage is 50 t, the first stage 50 t (16%structure) and 200 t propellant. On takeoff it masses 300 tons, less than a 747. A large airport handles a lot more traffic than 8 747 takeoffs and landings an hour.

    Hard engineering, no miracles required. Not cheap, the laser might eventually cost $40 billion. To get started (to positive cash flow) came out to $60 billion on a first cut proforma analysis.

    A UK company, Reaction Engines, has an inordinately clever approach to boost the effective exhaust velocity so as to actually put positive payloads (12 tons) into LEO with hydrogen/oxygen single stage to orbit. What they are doing is recovering a lot of the energy that goes into liquefying hydrogen and using that to compress air to rocket chamber pressures up to 26km and Mach 5+. Google for them. Also Google henson oil drum if you want more details.

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