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Power Science

Beamed Space Solar Power Plant To Open In 2016? 512

Eric_S writes "Anybody who managed to get a decent city going in Sim City 2000 remembers the microwave power plant; now it seems like a real-world equivalent might be coming up on the horizon. The Pacific Gas and Electricity Company, per this 'interview' with the CEO of Solaren on their affiliated site, announced PG&E's plans to buy 200MW of base-load power from a Solaren beamed space solar power plant by 2016." I wish the skeptic in me would be quiet.
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Beamed Space Solar Power Plant To Open In 2016?

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  • Demand? (Score:4, Interesting)

    by ComputerDruid ( 1499317 ) on Thursday June 25, 2009 @09:31AM (#28465509)

    While this kind of power beaming technology is possible, I can't imagine that it's all that efficient. Are we really low enough on other forms of power that there will be enough demand to support this kind of remote endeavor?

  • Bullshit (Score:1, Interesting)

    by Anonymous Coward on Thursday June 25, 2009 @09:31AM (#28465515)

    There is only one advantage to space based solar power: Essentially no night in space. That is not a good enough reason to shoot that much material into a geostationary orbit. Solar cells age faster in space due to hard radiation. The losses from wireless power transmission further reduce the feasibility. If anyone builds a solar powered microwave beam in space, that is clearly weapons technology, not even dual-use technology.

  • Global warming? (Score:2, Interesting)

    by steelmaverick ( 936668 ) on Thursday June 25, 2009 @09:32AM (#28465519)
    I'd be concerned with maybe its effects on the weather, maybe global warming. Also, this could affect radio communications on Earth. Or perhaps not, since it probably would operate off of a different frequency. Personally I think that geothermal energy is still a method of energy production that has yet to be tapped on a more massive scale. Why put up satellites and beam power back to Earth when we have excellent sources of power here?
  • Re:Global warming? (Score:3, Interesting)

    by internerdj ( 1319281 ) on Thursday June 25, 2009 @09:41AM (#28465631)
    My thoughts exactly. Have we really tapped all the energy sources here that are reasonable? Apart from the what if it misses and fries someone question, this project would beam extra energy into Earth's energy system. One system might not have a strong effect but lets not forget the law of conservation of energy here.
  • Re:Bullshit (Score:1, Interesting)

    by Anonymous Coward on Thursday June 25, 2009 @09:44AM (#28465669)

    If they use PV "solar cells" then yeah, I call bullshit too. I don't think they could possibly get enough into geosync orbit to generate 200MW.

    Now mirrors focused on something to spin a turbine powered generator I can almost swallow. Can they build it by 2016? I'm skeptical too.

    How about if we just eliminate the NIMBY aspect and build some of those mirror focused steam turbines on the ground first, and build out the transmission infrastructure so that Nebraska corn farmers who want to put up wind turbines can get the power they produce to the grid.

  • by StCredZero ( 169093 ) on Thursday June 25, 2009 @09:50AM (#28465723)

    For specific kinds of applications, yes, there is demand. DARPA is interested in this, because electronics use, and there fore electricity use, by the military has expanded tremendously, even in remote locations. A diesel generator has to receive a constant supply of fuel. This is very expensive and inconvenient on the top of a mountain in Afghanistan. A solar power receiving station doesn't. The power supply is invulnerable to attack. The receiving station doesn't make constant noise. In such contexts, power delivered at rates an order of magnitude higher than commercial generation is very competitive.

    We should build something like the Iraqi Super-cannon. The thing was built out of 70's tech and was slated to deliver stuff to orbit for $600/Kg. We could improve on that with new tech and mass production of the rocket-boosted projectiles. Construction materials for SPS could be packaged to survive the G's of being shot out of a cannon. Even electronic components could be built to survive. The US government has specs for electronic components that can survive 100,000 G. (Yes, one hundred thousand!) That would make SPS much cheaper.

  • Re:Miss (Score:4, Interesting)

    by ShieldW0lf ( 601553 ) on Thursday June 25, 2009 @09:54AM (#28465765) Journal
    Satellite in geostable orbit. Receiving station on equator. Receiving station emits guiding signal to satellite, causing satellite to beam power to earth. If the guiding signal is missing, the satellite stops beaming power and starts using that power to adjust it's position. That's how I'd do it.
  • by FaytLeingod ( 964131 ) on Thursday June 25, 2009 @10:02AM (#28465847)
    Assuming everything goes well and this becomes a viable source of energy What stops any oil producing nation from blowing it up?
  • Re:In Space (Score:4, Interesting)

    by goombah99 ( 560566 ) on Thursday June 25, 2009 @10:07AM (#28465907)

    lots of pissed birds, bats, pollen and insects too.

  • Re:Global warming? (Score:5, Interesting)

    by hort_wort ( 1401963 ) on Thursday June 25, 2009 @10:18AM (#28466053)

    I asked this question of an Environmental Physicist. The answer is that it will *prevent* global warming. The reasoning is this:

    Right now, we primarily burn coal to produce energy. This isn't an efficient process at all, putting out about 30% energy and 70% heat. Also, there are all the waste products dumped into the atmosphere associated with burning coal. Meanwhile, beaming the energy back to the Earth will (theoretically) be very, very efficient, as in almost all the energy beamed back will be reclaimed as electricity. Replacing coal with this method would reduce the overall heat by 70%.

    So yes, this idea will heat the Earth, but not nearly as much as coal. As far as causing other weather changes, health problems, and electronic problems, those are possibilities that are unknown until they try it. The signal should be directed quite precisely to their receiver on Earth, and with any intelligence, they will have a safety system such that the beam shuts off immediately if the receiver notices a dip in power.

  • Re:Demand? (Score:5, Interesting)

    by john.r.strohm ( 586791 ) on Thursday June 25, 2009 @10:27AM (#28466149)

    On power: The object of the exercise is to put the solar arrays in space, cut out all the atmospheric attenuation due to air and clouds, and then send the power down using microwaves, on wavelengths that are not significantly attenuated by air and clouds.

    On pointing: You've never heard of electronically-steered phased array radar, have you?

    On efficiency: When the Jet Propulsion Lab tested microwave power beam technology in the 1960s, between two mountains several miles apart, they were hoping to get 63% transmission efficiency. They actually got over 80%. (I think the number was 88%, but don't quote me.)

    The key concept on the efficiency question is that solar power in space is effectively unlimited, when compared with available solar power at ground level, because of atmospheric attenuation of light. (Photographers who shoot outdoors know all about this.) Once you have unlimited power at the head end, you don't really care very much about losses due to beamforming.

    My source on this is a talk given by Jerry Pournelle in Austin TX in the late 1970s. His slides included photographs of the actual test apparatus, including one of the lit-up light board at the receiving site.

  • Re:Human Size Ants (Score:3, Interesting)

    by Tx ( 96709 ) on Thursday June 25, 2009 @10:34AM (#28466237) Journal

    Since the OP didn't reply, I'll have a stab.

    "First, a "few times" noon sunlight power, I think would be pretty brutal."

    The OP was talking about transiting the collection area, not camping out there. Also we're talking about microwaves rather than visible/UV from sunlight, you will have to ask someone else what the equivalent energy of 3x noon sunlight in microwave form will do, but the point is we're not simply talking about noon sunlight x3, it's not visible/UV at all.

    "Doesn't a "few times" noon sunlight power mean that your getting only a "few times" what you'd be getting from the sun by itself..."

    Again, we're talking microwaves. Microwaves can be converted to electricity with an efficiency of 75% plus using a rectenna, this is many times the best efficiency we can currently achieve with visible light (typically ~15%). So if you have a beam energy density 3x sunlight, and a conversion efficiency 5x photovoltaics, that give you and output energy 15x what you would get directly converting sunlight using photovoltaics, not just 3x.

  • Extra Energy? (Score:2, Interesting)

    by Ironix ( 165274 ) <steffen AT norgren DOT ca> on Thursday June 25, 2009 @10:34AM (#28466245) Homepage

    Actually, isn't the satellite simply intercepting the energy that would have made it to the Earth anyhow?

    If this system has about a 50% efficiency, then isn't this satellite actually blocking the other 50% of said energy from actually ever reaching the earth?

  • by blind biker ( 1066130 ) on Thursday June 25, 2009 @10:39AM (#28466295) Journal

    So, the gigantic effort to put this solar plant into orbit will create... 200MW of power?

    Contrast to this: 0.3% of the Sahara could power the whole of Europe [guardian.co.uk]

    It's expensive like hell, sure, but it would start delivering energy long before it's completed and its goals are way more ambitious than this flying solar panel's! Think no more unrenewable energy, no more CO2, no more pollutants (sulphur, heavy metals etc.) from coal plants, no more soil erosion due to dams, no more gas or oil (yeah, in italy they have plenty of those) power plants. Only a few windfarms and perhaps the French nuclear plants to iron out the energy needs during night time.

    Don't tell me the USA has a lack of sun and deserts.

  • Re:Global warming? (Score:2, Interesting)

    by maxume ( 22995 ) on Thursday June 25, 2009 @10:55AM (#28466475)

    The sun strikes the earth with petawatts of power. On average, the earth radiates petawatts of power into space. Adding even a few terawatts to that will not shift the average temperature in any noticeable way. Gigawatts even less.

  • Re:Human Size Ants (Score:0, Interesting)

    by Anonymous Coward on Thursday June 25, 2009 @10:59AM (#28466523)

    This orbiting solar plant would have to be in a geosynchronous orbit to beam the energy to the antenna. It could not beam power 24/7.

  • by Anonymous Coward on Thursday June 25, 2009 @11:05AM (#28466601)

    I've noticed over my life, that incredible claims of new ways to deal with energy issues are '7 years out'.

    BlackLight Power back in 2000 were claiming a 'battery the size of a briefcase that can power an electric car 1000 miles' as an example.

    Now, here we have this new claim.

    Yet these people point out that the energy here on earth from one of the downlinks is only 2X that of regular old PV.
    URSI White Paper on Solar Power Satellite (SPS) Systems [ursi.org]

    So whom to believe? A guy seeking venture capital OR a bunch of wet blanket boffins?

  • by WindBourne ( 631190 ) on Thursday June 25, 2009 @11:33AM (#28466915) Journal
    The reason is that currently, the western militia there must import lots of fuel to provide electricity. That is EXPENSIVE. VERY EXPENSIVE. Instead, the groups could put up one of these that have say 5-50 MW and then put small collectors on the ground. It would be MUCH cheaper than bringing in the equipment and fuel. In addition, if a base is overrun, it would be easy to prevent enemy (read Al Qaeda) from using the equipment and new equipment would be much lighter, easier to take care of, etc. Also, once several of these were up there, they could be shifted around to help on Emergency locations. For example, helping Hurricanes, tsunami, Chinese EarthQuake, 9/11, etc. The ability to get power into a large disaster area means, LITERALLY life or death. If we put at least one over every major continent, they could be used normally to help a city that already has coal/gas, but then moved ahead of time for when a disaster is heading there way (hurricanes), or a day or two for unseen disasters that happen. Heck, if done right, private space industry should push this private tugs. These can then be used for doing other work (perhaps getting rid of space junk).
  • Re:Extra Energy? (Score:3, Interesting)

    by Lumpy ( 12016 ) on Thursday June 25, 2009 @11:43AM (#28467035) Homepage

    That does in fact block a lot of energy. ever been in a total eclipse? I have, it get's cold! It's a incredible example of how much energy the sun actually get's to the earths surface.

  • Re:Human Size Ants (Score:3, Interesting)

    by QuoteMstr ( 55051 ) <dan.colascione@gmail.com> on Thursday June 25, 2009 @11:46AM (#28467079)

    Except that in space, you don't need to deal with atmospheric attenuation. That increases the effective power output of your solar cells quite a bit, even if their efficiency is the same. 50% (to pick an arbitrary figure) of 500MW is a lot more than 50% of 250MW.

  • Re:In Space (Score:4, Interesting)

    by oni ( 41625 ) on Thursday June 25, 2009 @11:49AM (#28467113) Homepage

    [citation needed]

    See, I think that your comment is FUD. I think that if these microwaves are at the right frequency to excite water molecules (and thus hurt animals) that they'd also be absorbed by the atmosphere and thus not useful for the transmission of power. But every time this story comes up, someone makes a post based on fear. How sad.

  • Numbers (Score:3, Interesting)

    by Baldrson ( 78598 ) * on Thursday June 25, 2009 @11:58AM (#28467255) Homepage Journal
    The launch costs (Falcon 9 $2500/kg) of satellite solar panels (30W/kg with 15 year lifetime) and basically 0% interest rate (straight line depreciation over 15 years) yields a little over 60 cents per kWh at the satellite. Account for transmission losses and you're talking over $1/kWh at the grid.

    They must have some big economies somewhere they aren't talking about to make this profitable.

  • Re:Human Size Ants (Score:3, Interesting)

    by Bakkster ( 1529253 ) <Bakkster.man @ g m a i l .com> on Thursday June 25, 2009 @12:01PM (#28467289)

    If wifi,bluetooth and am/fm waves are so similar, there must be plenty of energy floating around us. Why can't we just recover that energy? Power your laptop from your WiFi signal. Heck, with all the radio stations transmitting around us we should be able to pluck a few dozen frequencies and power the radio itself.

    How efficient are these antennas again?

    The stray microwave radiation is of a much lower average power. In addition, it is spread across a much larger spectrum, making it difficult to grab all the energy at once.

    This plant will send a higher power, focused beam of a single frequency, making it highly efficient. Nokia is working on a system like you describe, though it only gets about 10mW of power currently.

  • by blind biker ( 1066130 ) on Thursday June 25, 2009 @12:40PM (#28467905) Journal

    True enough, I agree!

    But there wouldn't be such implications if the USA built such a powerplant somewhere in Nevada, Utah or Arizona (or New Mexico, Idaho or... there's plenty of deserts in your country).

    Compared to the USA, Europe is pretty fucked, when it comes to free areas with plenty of sunlight. But, EU politicians are sucking enough Arab dick, that the political climate may be somewhat favorable for us to build some plants in Morocco and Egypt, perhaps even Algiers, and with enough sucking, Mauritania and Libya are also possible options.

  • Re:200MW. (Score:3, Interesting)

    by yuna49 ( 905461 ) on Thursday June 25, 2009 @12:40PM (#28467913)

    Still the economics of this are a bit puzzling. In 2008, California used 285 million megawatt-hours [ca.gov] of electricity, so even if this project could generate 200 MW 24x7 that still comes to just 511,000 megawatt-hours per year, or a little under 0.2% of Californian consumption. At a wholesale price of $50 per megawatt-hour [doe.gov], that would earn Solaren about $25 million per year. Even over the fifteen year projected lifespan that comes to just $375 million (actually less if you take inflation into account). Is $375 million anywhere near what the actual cost of this project will be? Space engineers, please help here.

  • Re:Miss (Score:3, Interesting)

    by afxgrin ( 208686 ) on Thursday June 25, 2009 @01:16PM (#28468511)

    A phased-array antenna at 2.45 GHz still has a rather wide beam. I would say that a parabolic reflector has a narrower beam than a phased-array antenna - especially at 2.45 GHz. If this were operating at a higher frequency, then sure, you can get a pretty tight beam, but then you start having other atmospheric absorption problems. Rain would be terrible at just about any higher frequency, not to mention oxygen and nitrogen also start absorbing the higher in frequency you go.

    Plus - a really tight beam has many negative problems - if you keep a really high power density - the lower air pressure in upper parts of the atmosphere are likely to form plasma. The electric-field strength due to the high power density can cause that flash over to occur, and once that plasma forms - oh shit - all sorts of weird things can happen. The plasma can start reflecting RF energy, it can just keep absorbing it, and it may even let some through - but it's more likely to reflect or absorb once the plasma is formed.

    Any way - back to the phased array thing - the main benefit of phased-array transmitters is the ability to steer the beam with no moving parts.

    Works great for radar systems - less so - in my opinion for microwave power transfer.

    This company really just needs to launch a test satellite first, but you would want to test it at a very high power density, because that's what's needed, as that's when all the weird effects start to happen. Lots of ground experiments would need to be performed, but even then - the whole thing could get launched, and some unforeseen consequence happens, and we've just wasted billions upon billions of dollars.

  • by blind biker ( 1066130 ) on Thursday June 25, 2009 @02:20PM (#28469535) Journal

    Also, if you think orbital solar is expensive, imagine trying to string HVDC lines across hundreds of miles of shifting sand dunes, then under the Mediterranean sea or across Gibraltar. Then think how expensive it'll be to send people into the middle of one Earth's largest deserts to service all this equipment. It makes space look cheap.

    You are wrong about this. The 200MW this space gimmick will produce is a drop in the ocean compared to what terrestrial mega-plants can produce. Besides, we already have oil drilling sites in much less hospitable (both politically as well as environmentally) places, and we have to build thick pipe lines to carry that oil, and the servicing of such infrastructure is way more complex than a solar powerplant of the same energy output. AND in addition to all this, the oil drilling site is temporary - it is exhausted after a while so either we have to build new drilling sites nearby, or if the whole area is exhausted, the whole pipeline is worth shit! And in spite of all this, it's still very profitable to do this. I submit to you that it is even more profitable to do the same in case of a gigantic solar plant. The energy harvested is many times more, and it is practically inexhaustible.