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Obama Transition Team Examining Space Solar Power 275

DynaSoar writes "President-elect Obama's transition team has published for public comment a white paper entitled Space Solar Power (SSP) — A Solution for Energy Independence & Climate Change. The paper was prepared and submitted by the Space Frontier Foundation and other citizen space advocates, and calls for the new Administration to make development of Space Solar Power a national priority. The SSP white paper was among the first ten released by the Obama transition team. It is the first and only space-related white paper released by the team to date. With 145 comments thus far, it is already among the top five most-discussed of the 20-some white papers on"
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Obama Transition Team Examining Space Solar Power

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  • How? (Score:3, Insightful)

    by Tubal-Cain ( 1289912 ) * on Saturday December 20, 2008 @05:55PM (#26186525) Journal
    And how exactly do they plan on getting the panels/mirrors/whatever up there []?
    • Re:How? (Score:5, Insightful)

      by Samschnooks ( 1415697 ) on Saturday December 20, 2008 @05:57PM (#26186539)
      Outsource to the EU, Russians, or the Chinese?
      • Re:How? (Score:5, Insightful)

        by east coast ( 590680 ) on Saturday December 20, 2008 @06:03PM (#26186583)
        I thought Obama's plan was to keep the jobs and technology home based. After all, outsourcing doesn't do much to create jobs.

        he's either going to have to do this with NASA and keep their funding up or it's just more banter from a politician.
        • Re:How? (Score:5, Insightful)

          by peragrin ( 659227 ) on Saturday December 20, 2008 @06:16PM (#26186695)

          Obama doesn't want to kill NASA, Obama wanted to streamline a few of NASA's pipe dreams Like returning to the moon or manned mars missions. Things that have little practical value in the next 5 years. a return trip to the moon would only be for historical reasons and maybe to bring back a few more moon rocks.

          • by hax0r_this ( 1073148 ) on Saturday December 20, 2008 @06:28PM (#26186761)
            Yeah, and a trip to the west coast after the Lewis and Clark expedition would only have been for historical reasons and maybe bring back a few more notes.
            • by Eskarel ( 565631 ) on Saturday December 20, 2008 @06:42PM (#26186865)
              Exploration most certainly does have value.

              That said, expensive exploration, without the means to capitalize on it, when the economy is in trouble and we're trying to cut our energy use probably doesn't have a whole lot.

              Nothing wrong with sending more landers, probes, etc to mars, the moon, wherever else we can get em. It's expensive, but it's potentially valuable. Sending a person somewhere just to say you've sent them somewhere is really rather silly.
              • by gregbot9000 ( 1293772 ) <> on Saturday December 20, 2008 @10:02PM (#26188021) Journal

                Exactly, what really needs to be known is if their is water on the moon, and how much, first. That can be done through probes a lot cheaper.

                If there is an ocean at the pole than sending people up at a later date would make sense because you could then extract essentials in-sutro, saving lots on resupply missions, and with the low gravity potentially allowing longer stays than Micro G saving cost on replacing crew. Which could then possibly assemble more probes on the moon cheaper then pushing them up the gravity well or even catch a NEO. Why we haven't figured out the most important part of future space travel (what resource's are easy and cheap to get off the moon) through cheap probes yet I can't figure out.

              • Re: (Score:3, Insightful)

                by nine-times ( 778537 )

                Nothing wrong with sending more landers, probes, etc to mars, the moon, wherever else we can get em.

                Especially if you suspect that these places might have resources that we can figure out a way to use. Exploration for the sake of exploration is fine and dandy, but that's not generally why human exploration has happened. The reason people sailed across dangerous uncharted areas has usually been because they expected to find something of practical/financial value on the other side.

            • by Waffle Iron ( 339739 ) on Saturday December 20, 2008 @10:10PM (#26188069)

              Yeah, and a trip to the west coast after the Lewis and Clark expedition would only have been for historical reasons and maybe bring back a few more notes.

              If Lewis and Clark had come back reporting that there was nothing on the west coast but dust, no economically extractable minerals, and that had zero atmosphere and only trace amounts of water, and that another trip would cost multiple billions of 2008 dollars, and a colony would cost hundreds of billions, then there would indeed have been no reason to go back.

            • Re: (Score:3, Insightful)

              by Teancum ( 67324 )

              As if NASA has done much original exploration lately. How long has it been since anybody has been to the Moon?

              About the only genuinely ground breaking missions currently on tap are the New Horizons [] mission to Pluto and the Dawn [] mission to the asteroids. I am excited about both, but they certainly don't need an agency the current size of NASA to support either or both missions.

              The spirit to boldly go where nobody has been before seems to be lost right now with NASA. No astronauts are setting altitude (aka

          • Re: (Score:2, Insightful)

            by Anonymous Coward

            Landing on the Moon is not a pipe dream, we've done it. Going to Mars is not a pipe dream, it's a plausable extension of the capabilities we have today. Both of these can be done for reasonable cost, and in the process spur innovation and boost our national prestige. Given the fact that we appear to be in a national malaise, the latter should not be considered trivial.

            The pipe dream here is solar space power. It's an absurd concept that will never be profitable compared to Earth-based utilities. Even the su

            • The atmosphere absorbs around 25% of sunlight on a sunny day, and you have nighttime and clouds. So a solar collector in space produces around 5 times as much raw power as one on the ground. Space solar power makes sense if *ALL THE OTHER COSTS OF GETTING THE POWER DOWN TO THE UTILITY GRID* are less than 5 times as high. Otherwise ground based solar power is cheaper.

              Right now, the cost equation says it does not make sense. Some combination of cheaper launch methods, robotic construction, and supply of 9

          • When it comes down to it just about everything NASA has ever done outside of contributions to satellite technology has "little practical value" to us today. But those of us who can see the forest in spite of the trees knows where the value of all these other "pipe dreams" lies.

            And I always thought that the new moon missions were to focus on a permanent colony. I think that's a little bit better than "bring back a few more moon rocks."
          • Personally I vote for putting something really cool in L4 or L5, like a space telescope or some sort of communication relay.
        • Re: (Score:3, Insightful)

          by Teancum ( 67324 )

          Why does this have to involve NASA at all? Yes, NASA seems to be the agency with experience in dealing with spaceflight, but NASA certainly isn't the only (nor even the largest agency in the U.S. government) that is involved with spaceflight.

          In terms of dollars actually spent on spaceflight, I don't know which is larger: The NSA (National Security Agency... who operate the spy satellites and hack into the internet) and the U.S. Air Force Space Directorate. Both are larger than NASA. The Air Force at one

    • by Anonymous Coward
      As usual, just throw money at NASA and ignore it when it doesn't work since it's really pork.
    • Re: (Score:3, Interesting)

      by meza ( 414214 )

      Well stuff has been put up in space before. No biggie. What I'm wondering is how they plan to get the energy back down here.

      Any one have links to actual engineering proposals of how Space Solar Power would work and its benefits? Seems to me like "space" is not one of them, there is plenty of desert and whatnot to put solar cells in here on earth with much less maintenance cost and of course the possibility of running wires to get the energy to wherever it is actually needed.

      • Re:How? (Score:4, Informative)

        by Socguy ( 933973 ) on Saturday December 20, 2008 @06:13PM (#26186665) []

        Beam the energy in the form of microwaves to rectennas on the ground.
        • Numbers? (Score:4, Informative)

          by hax0r_this ( 1073148 ) on Saturday December 20, 2008 @07:07PM (#26187025)
          Well, I can't find any really great numbers, but heres what I have:

          According to the article from the Economist linked below 1.3 GW of solar energy pass through every square kilometer of space (presumably this is near Earth).

          According to Wikipedia, nuclear power plants on earth had a total capacity of 366 GW in late 2005.

          So by some rough calculations, assuming 100% efficient panels we would need ~280 square kilometers of solar panels in space just to gather as much energy as we can currently produce with nuclear power.

          Today, even highly experimental solar cells don't reach 50% efficiency. So 2 * 280 = 560.

          Now I can't find any good numbers on the efficiency of this "beaming" energy back to earth, but I'm going to throw out that 10% would be generous, its probably way less. But assuming 10%, 10 * 560 = 5600 square kilometers of solar cells in space just to get as much useful power as we get from our dismal nuclear setup today.

          And thats not to mention the size of antennas you would need on either end to beam that power, or the safety issues involved (you think windmills or low frequency submarine radios kill a lot of birds, how about a 3.6 TW microwave beam?)
          • Re: (Score:2, Informative)

            You don't use panels 'directly'. You use thin film mylar/reflective surfaces and focus a beam to ( some central generator station ). The ( ) are because there are plenty of ways to take a concentrated beam of sunlight and turn it into energy.

            I agree with the paper ( as much of it as I've read ) in that 'this WILL happen someday'. But it won't be anytime soon. Worth looking into? Ehhhh. Dunno. I'd love to see it. Personally I think researching it to be a better use of NASA's bucks than a moon shot.

            But I also

          • I love the idea of beaming power down from space to earth to provide us with electric power. Here are a few problems;

            1. For a power source to remain stationary over North America would require a solar array in geostationary orbit (Clarke orbit or Clarke Belt) where we have commercial satellite systems. It is irrelevant to worry about collisions with geostationary satellites as the Clarke belt is approximately 165,000 miles long. The distance from earth is approximately 22,236 miles from earth.

            For a closer o

            • Re: (Score:3, Informative)

              by jstockdale ( 258118 )

              Um ... not to nit-pick, but free-space losses are for isotropic radiation, and can be compensated for by a high gain antenna -- remember that lasers are also em-waves -- a perfectly focused beam, if technologically possible to generate, would travel through a vacuum indefinitely (otherwise, it'd be a violation of conservation of energy, no?). So, throw a well designed antenna system up there and although you still won't have 100% efficiency, it certainly won't be 1/150th of the power generated in geosync.

          • Re:Numbers? (Score:5, Interesting)

            by rbrander ( 73222 ) on Saturday December 20, 2008 @09:54PM (#26187965) Homepage

            I read the Economist article and noted the name of the scientist ("Mankins") who researched it.

            I typed "mankins microwave transmission efficiency loss" into Google and the second link was an IEEE article with the abstract appended below.

            Your number is 45% for DC-to-

            So not assuming that solar-cell efficiency can make it to 50%, but cheerfully assuming that the kind of cells that will do well in an industrial setting space for long periods can reach today's in-the-lab max of 40%, your area comes to:

            560 km^2 / 40% / 45% = 3111 km^2.

            And so what? There's a lot more space than that out there. (See opening paras of Hitchhiker's Guide for how much.) The question is the available money, not the available space. Those 556GW of nuclear had a total capital cost of well over a trillion. (And a land area sucked up of well over 3111 km^2 by the way, add up all the mines and waste dumps and reprocessing facilities, not just the plants. And that's area we can use for other things, down here; not a lot of other things to do with 3111 km^2 of orbit.)

            The Economist article is unequivocal: SSP would cost FIFTY CENTS per kWh. That's just awful, way worse than earth-based solar or wind, even backed up with 85 watts per 100W so that they are base-load capable.

            But one lives, and allocates research dollars, in hope. I'd bump the fusion budget from $300M to $500M, and match that with SSP research funds...about $400M of which would go to "cheaper lift costs", the truly key barrier.

            Space solar power programs and microwave wireless power transmission technology
            McSpadden, J.O.; Mankins, J.C.
            Microwave Magazine, IEEE
            Volume 3, Issue 4, Dec 2002 Page(s): 46 - 57
            Digital Object Identifier 10.1109/MMW.2002.1145675
            Summary: Future large-scale space solar power (SSP) will form a very complex integrated system of systems requiring numerous significant advances in current technology and capabilities. Ongoing technology developments have narrowed many of the gaps, but major technical, regulatory, and conceptual hurdles remain. Continuing systems concept studies and analyses will be critical to success, as will following a clear strategic R&T road map. This road map must assure both an incremental and evolutionary approach to developing needed technologies and systems is followed, with significant and broadly applicable advances with each increment. In particular, the technologies and systems needed for SPS must support highly leveraged applicability to needs in space science, robotic and human exploration, and the development of space. Considerable progress has been made in the critical area of microwave power transmission. At 5.8 GHz, DC-RF converters with efficiencies over 80% are achievable today. Rectennas developed at 5.8 GHz have also been measured with efficiencies greater than 80%. With optimized components in both the transmitter and rectenna, an SPS system has the potential of a DC-to-DC efficiency of 45%.

          • Re: (Score:3, Interesting)

            by JoeMerchant ( 803320 )
            Think: mirrors, concentrated sunlight on a generating station in the desert - or, on unruly cities, or troublesome mountain ranges with AlQueda infested caves.
        • Yup, but: (Score:2, Informative)

          by John Guilt ( 464909 )

          0.) You fill out the environmental impact statement (because this is not Soviet Russia!).
          1.) Do we want to get a lot of power from something so vulnerable to easily-deniable sabotage?
          2.) Any such device could also pass muster as a death-ray; this might raise objections from a Major Creditor Nation.

      • Re: (Score:3, Informative)

        The concept has been kicking around for years. It generally calls for getting the power back down via microwaves. []
    • by aliquis ( 678370 )

      And why? I mean, if you pick up additional energy from space and transfer it to earth, won't that heat it up to? =P

  • by mind21_98 ( 18647 ) on Saturday December 20, 2008 @06:01PM (#26186571) Homepage Journal

    Doesn't this remind you of the microwave power plants in SimCity? To me, it does. :)

    • Actually it reminds me of the Orbital Power Transmitter in Sid Meier's Alpha Centauri/Alien Crossfire. (Speaking of which, anyone have a comprehensive list of Alpha Centauri-Civilization series equivalents? I mean, I can get formers/settlers, doctor/entertainer, talent/happy citizen and stuff like that, but I mean a list of all the technologies, weapons, secret projects, etc.)

      Anyway, I guess the main challenge is beaming the power down to earth without frying someone's nuts off.

  • Pie in the sky (Score:5, Insightful)

    by yog ( 19073 ) * on Saturday December 20, 2008 @06:03PM (#26186593) Homepage Journal

    I'm sorry to say, this SSP white paper is simply that--a piece of paper with a pie-in-the-sky proposal that is unlikely to get funded to the same extent as fusion energy by the DOE.

    Since it's a space-based project, it should really be funded and organized by NASA, which after all knows something about orbital solar arrays, while the DOE is merely an umbrella bureaucracy without a clear mission. Jimmy Carter set it up, as I recall, and during the laissez-faire Republican administrations as well as the Clinton years, it has been primarily a custodian for regulating fission reactors and funding some research projects.

    There is so much potential for reaping energy savings on land, without having to resort to dangerous space flights and risky, massive construction projects in orbit, that it's amazing that this proposal is even being looked at by the transition team. I suspect this is fake news.

    Don't get me wrong--I'm a total space nut, and I want to see us spending a trillion a year on space, and spread our civilization out to the planets before we blow this one away.

    But when we can reap significant energy savings merely by painting the rooftops white of most government buildings, when we drive cars that have half or one third the fuel efficiency they could have, when we live in uninsulated buildings--it's ridiculous to proclaim that an SSP would solve our energy problems.

    We should definitely build orbital facilities that would include solar arrays, perhaps to house dangerous manufacturing operations and to do zero-grav research, but this is not the most persuasive white paper that they are going to look at, I suspect.

    • Re:Pie in the sky (Score:4, Insightful)

      by DynaSoar ( 714234 ) on Saturday December 20, 2008 @06:32PM (#26186795) Journal

      I'm sorry to say, this SSP white paper is simply that--a piece of paper with a pie-in-the-sky proposal that is unlikely to get funded to the same extent as fusion energy by the DOE.

      I almost added some similar editorializing to the submission, but opted to leave it as it was. I'm also very skeptical of the proposal itself. However, I find the interest in it as compared to the other proposals on to be encouraging. This is especially so since Obama was at first hardly pro-space. Their interest in this proposal is another step away from that stance. And I believe Obama's team still to be capable of being influenced and directed to better things. This proposal is too far off, but it makes a good focus point for choosing a more positive direction. O'Neill's ideas were similarly distant, but they persist as well developed starting points.

      • From here on getting things done in space will require a twenty to thirty year outlook. Unmanned exploration can get away with that by being cheap, but manned programmes need constant political support and it is hard to get that for more than ten years at a time.
    • when we drive cars that have half or one third the fuel efficiency they could have,

      Gasoline engines are more efficient now than they were in the 70s however due to the increased weight that many vehicles possess the resulting MPG is less. When you put a 400HP engine in a crossover utility vehicle (XUV) weighing almost 2 tons you tend to not get that great of gas mileage however the efficiency is still there as far as I know (I'm not an engine builder).

    • by IdahoEv ( 195056 ) on Saturday December 20, 2008 @07:31PM (#26187167) Homepage

      There is so much potential for reaping energy savings on land, without having to resort to dangerous space flights and risky, massive construction projects in orbit, that it's amazing that this proposal is even being looked at by the transition team.

      I'm also a space nut, and I agree with you completely. A simple look at cost/benefit, even back-of-the envelope, makes it entirely clear how silly orbital solar is.

      1) Benefits - how much energy can an orbital solar array produce, relative to the same size solar array on Earth? About twice as much - it's lit for 24 instead of 12 hours. (plus benefit of always-perpendicular incident radiation, but minus losses in conversion & transmission.) Ultimately, ~2x power from the same array.

      2) Costs - how much does it cost to put that solar array in orbit, and build the microwave transmission system, relative to the same size solar array on Earth? Answer: an awful lot more than 2x. More like 100x.

      Paying 100x cost for 2x the power generation is not anyone's idea of good economics. End of story.

      It's just so much cheaper to simply build twice the arrays on the ground, even if you have to build huge power storage facilities or around-the-world ultra-high-voltage power lines to funnel energy to the night side of the planet.

      Maybe in 100 years we'll have a developed space industry that can build them, up there, on the cheap. But certainly not any time soon.


      • However, it makes people that care about the earth and its other creatures and don't want to pave over it with Solar Panels or Concrete.
    • There is so much potential for reaping energy savings on land, without having to resort to dangerous space flights and risky, massive construction projects in orbit ...
      when we can reap significant energy savings merely by painting the rooftops white of most government buildings, when we drive cars that have half or one third the fuel efficiency they could have, when we live in uninsulated buildings--it's ridiculous to proclaim that an SSP would solve our energy problems.

      If it's so simple and cheap t

  • Isn't BHO opposed to that?

  • by Baldrson ( 78598 ) * on Saturday December 20, 2008 @06:11PM (#26186645) Homepage Journal
    Interestingly it was Gerard O'Neill who argued in the 1970's for solar power satellites constructed from lunar material and, as part of that argument predicted the industrialization of China would lead to increased CO2 emissions from coal burning that would mandate radical restructuring of global energy technology. It may be too late now to pursue nonterrestrial material SPS since the baby boomer generation, raised and educated to pioneer space from childhood, was denied that opportunity by --- well that is the question of the millennium if not the epoch isn't it? There are almost as many answers to that question as there are religions.

    there was an obvious direction in place subsequent to the space race (remember the Apollo program?) that would have been followed through to space industrialization had the launch service industry enjoyed the same protection from government competition that the satellite industry enjoyed:

    * (c) Private enterprise; access; competition

    In order to facilitate this development and to provide for the widest possible participation by private enterprise, United States participation in the global system shall be in the form of a private corporation, subject to appropriate governmental regulation. It is the intent of Congress that all authorized users shall have nondiscriminatory access to the system; that maximum competition be maintained in the provision of equipment and services utilized by the system; that the corporation created under this chapter be so organized and operated as to maintain and strengthen competition in the provision of communications services to the public; and that the activities of the corporation created under this chapter and of the persons or companies participating in the ownership of the corporation shall be consistent with the Federal antitrust laws. []

    It wasn't until 1990, when a coalition of grassroots groups across the country lobbied hard for 3 years, that similar legislation got passed for launch services. []

    The fact that Malthusian paradigm didn't follow the Club of Rome model doesn't change the reality of the Malthusian paradigm given a fundamentally limited biosphere undergoing its largest extinction event in 60 million years. The Club of Rome merely added academic fashion to the urgency of the Malthusian situation still facing the biosphere. The 1970s was the right time to start the drive for space industrialization based on a private launch service industry. It didn't happen, the pioneering culture that founded the US is being replaced by government policy with less pioneering cultures and now we're all facing some increasingly obvious difficulties -- not just pioneer American stock -- and not just humans.

    The cost of getting silicon into space from the lunar surface would be orders of magnitude less than launching from earth due not only to the much shallower gravity well but also due to the absence of atmosphere.

    No beanstalk needed.

    At worst a Dyneema Rotovator would be needed but probably not even that.

    First, the bulk of the materials are manufactured in space from lunar raw material transported to orbital facilities so you don't need to land those facilities on the lunar surface, and you don't have to worry about g-loading the raw materials you are sending to the orbital facilities.

    Second, you don't manufacture everything in space -- only bulky materials like solar cells, reflectors, structural members and perhaps klystrons. Only residual materials (raw and manufactured) are of terrestrial origin.

    Third, the facility you do put on the lunar surface is there primarily to transport raw mater

    • Perhaps no lunar beanstalk is needed, but any kind of non-conventional launch system from the moon to lower earth orbit will be much easier than going from the surface of the earth to lower earth orbit. I expect we'll see a variety of activity in that area once the powers that be start to realize just how high the stakes are here.

      • by Baldrson ( 78598 ) *
        True, and I presume that by "lower earth orbit" you don't mean "low earth orbit", but that geostationary orbit is lower than lunar orbit. What you say is particularly true of geostationary orbit, where solar collection is more continuous.
    • Then we should have continued on from Apollo. Build a small base and a reliable transportation system. The Saturn V was too expensive and the program had to stop.

      Doing it that way adds at least 20 years to the timeline. But if you want to build anything big it has to be made either on the moon or on a near earth asteroid.

      The fact is that nobody is going to build large scale SPS in the next hundred years.

      But I can believe orbiting mirrors to keep solar power plants working at night. Mirrors can be made
      • Please review my statements about private launch services and the difference in policy with the prohabition of NASA from competing in communications satellites. Apollo was simply the wrong paradigm -- it was technosocialist. If there is one thing that socialism fails at miserably it is investement risk management of pioneering technologies.

        The need for WPA style programs isn't sufficient to discipline government bureaucracies the way they were with the Manhattan and the Apollo program. There has to be

  • From The Economist (Score:5, Interesting)

    by airfabio ( 6375 ) on Saturday December 20, 2008 @06:14PM (#26186669)

    Recent space solar power article from The Economist []

    • by leerpm ( 570963 )
      Mod-up. It's a great article. SSP is a ways off from being economical viable for domestic/mass-consumer use, there are other applications (i.e. military) where the current cost/kWh is higher and SSP is more feasible in the short-term.
    • Nice read. Makes quite a bit more sense the TFA.
    • by a.ameri ( 665846 ) *

      Excellent read. Full of information, with lots of insightful details. The Economist never disappoints, it's an awesome publication.

      The fact that it publishes the content of its print edition online, one day BEFORE the print edition is delivered, and it has still been able to massively increase its subscriber numbers (doubled in the past 3 years), just shows to prove that even in this age of Internet, when everyone else in the newspaper industry is complaining about falling revenues, good journalism has its

  • The link is just a one page overview and doesn't really tell you much. The idea in a nutshell: "The basic idea is very straightforward: place very large solar arrays into continuously and intensely sunlit Earth orbit (1,366 watts/m2) , collect gigawatts of electrical energy, electromagnetically beam it to Earth, and receive it on the surface for use either as baseload power via direct connection to the existing electrical grid, conversion into manufactured synthetic hydrocarbon fuels, or as lowâinten
  • by macraig ( 621737 ) <> on Saturday December 20, 2008 @06:19PM (#26186717)

    Perversely, my articulate question submitted to, asking when and whether we could expect to see sustainable off-planet colonization receive some significant priority, was virtually ignored. It was even "modded down" by some people.

    If we're gonna talk about exploiting solar energy in space, we should be talking about colonizing space in the same breath. If nothing else, the technical challenges of transferring that energy from space down through a thick atmosphere to the surface of the Earth should warrant a discussion of just moving us all closer to the source in the first place.

    • If nothing else, the technical challenges of transferring that energy from space down through a thick atmosphere to the surface of the Earth should warrant a discussion of just moving us all closer to the source in the first place.

      Given that the technical challenge is all but non-existent - why does that warrant such a discussion? (Or, "Even though your question was articulate, it is obvious that it was nonsensical".)

      • by macraig ( 621737 )

        If you perceive that technical challenge to be non-existent, perhaps you'll need to explain how and why. Some of us apparently aren't as expert on the topic as you are. After perusing your blog, I can clearly see that you attempt to tackle much bigger social and technical issues than I do, so I need the benefit of your highly specialized experience and knowledge of this topic.

    • Re: (Score:3, Informative)

      by hardburn ( 141468 )

      If nothing else, the technical challenges of transferring that energy from space down through a thick atmosphere to the surface of the Earth should warrant a discussion of just moving us all closer to the source in the first place.

      This problem is the most straightforward one. There are two holes in the spectrum normally blocked by the Earth's atmosphere, one in the microwave range and the other in light (infared, I think). Both are easy to transmit and convert back into electricity.

      The problem that isn't

      • by macraig ( 621737 )

        I wouldn't want to be the unfortunate bird or jetliner that happens to wander into the path of such a concentrated beam of radiation, regardless what particular wavelength in the spectrum it occupies!

        BTWnot blocked".

        • Why? SimCity was just a game looking for an additional disaster scenario. They're forms of non-ionizing radiation. In the case of the microwaves, they're too spread out to warm up the air by more than a few degrees. They're meant to be captured by rectennas spread over farm fields and still allow crops to be grown underneath. I haven't studied the laser proposals as in-depth, but it would be a very thin beam.

      • by synaptic ( 4599 )

        What if we could construct an initial segment of the power collector using conventional means (rockets, etc.) and begin beaming that power back to earth.

        Then it seems like instead of having a "rectenna" on the ground, you have it on a cargo craft. The energy it captures is used to power it's ascent. Sort of like beaming up, it needs to stay in the path of the energy beam and can ride it all the way to the array.

        Astronauts or automation then offload the payload, attach any materials for return to Earth, an

    • by amorsen ( 7485 )

      If nothing else, the technical challenges of transferring that energy from space down through a thick atmosphere to the surface of the Earth should warrant a discussion of just moving us all closer to the source in the first place.

      Moving a significant fraction of the Earth population into space isn't going to happen unless we find a way to get essentially unlimited energy on Earth. And if there's plenty of energy on Earth, why move more than a few colonists?

      • by macraig ( 621737 )

        We had almost unlimited energy, didn't we? Perhaps we should have been more focused on investing that energy to give us better long-term returns, rather than borrowing against it to buy the energy equivalent of cars and 52-inch plasma TVs?

        I think it's still feasible, but we need to be focused in a way that would be truly historic for the species.

      • by khallow ( 566160 )

        Energy has reached this threshhold on Earth already. For example, the average US home consumes enough energy each year in the form of electricity to put somewhere around 500 kilograms into escape velocity. I assume the average consumption of electricity is roughly 1 kW and that it takes, ignoring air resistance and gravity losses, 60 MJ of kinetic energy is contaiend in one kilogram of mass accelerated to escape velocity, 11 km/s. If energy was the restriction, then the US alone would be able to put an amaz

    • by J05H ( 5625 )

      Colonization and other industrial activities can evolve from SSP if done as public-private enterprise. Enable sSP to create a much larger launch market - the govt. can enable businesses to build, fly and operate SSP. Flight frequency is the #1 determinant of cost-of-launch. Hundreds of SSP component launches per year would open up space access to vastly more organizations and individuals, hence enabling settlement and development.

      The best thing the govt. can do is create an open environment for making this

  • by Anonymous Coward

    this wacky idea of harnessing solar energy seem rather rube goldberg-ish. if you read the original concept paper [] you would know there are flywheels and giant vacuum tubes on this thing. aside from that, the ultraprecision for positioning this monstrosity is beyond anything humans have ever done. no worries though, when a giant beam of radiation accidentally hits the wrong place, im sure the people wont mind being irradiated.

    in short, this idea is insane.

    • as opposed to lighting fire to rocks to create heat to boil water to create steam to turn turbines to move magnets to pull electrons to power capacitors (which are sometimes flywheels) to store extra power for peak times is so much worse than putting a flywheel in space.

    • I suppose you think a microwave oven irradiates your food, too. Planes already fly through the beams emitted by radar installations all the time, and nobody even notices the heating effect caused by that. Does anybody have actual figures on the energy density of the beam used for space-based power, and how long it would have to remain on target to produce real health effects?
  • by Khyber ( 864651 ) <> on Saturday December 20, 2008 @07:52PM (#26187281) Homepage Journal

    We haven't even come close to getting terra-based solar power up and going as a mainstream energy alternative. Let's work on the ground before we put things in the air, gentlemen.

    • by mikelieman ( 35628 ) on Saturday December 20, 2008 @08:25PM (#26187457) Homepage


      The sun NEVER SETS in GEO.

      and once you build the infrastructure to build/service the constellation of satellites, you have the infrastructure to go to the Moon, Mars, Titan and anywhere else you care to go.

      This technology simply is the killer-application which will drive American domination of the Universe.

      And if it ain't us, it'll be the Chinese. Your choice.

      • by GileadGreene ( 539584 ) on Saturday December 20, 2008 @09:08PM (#26187697) Homepage
        Actually, the sun does set in GEO. Just not for very long, and only at certain times of the year. Eclipse seasons for a geostationary satellite occur around the vernal and autumnal equinoxes. The seasons last around 40-50 days, with maximum sun-occultation duration of about 72 minutes. A discussion of the relevant orbit geometry can be found here [].
      • by Khyber ( 864651 ) <> on Saturday December 20, 2008 @09:57PM (#26187989) Homepage Journal

        Why? Lots of reasons, the most important being:

        A. Cost of putting such a LARGE array up there.

        B. Inefficiencies in power transmission (how're you going to beam it to the surface? Microwaves? Why not just harness it at ground level and store it in batteries, and cut out several points where conversion losses would be found?)

        C. Maintenance costs/damage protection/prevention - just how do you plan on keeping these things safe from random space debris flying at ultrasonic speeds?

        D. energy costs to build/deploy - these things would have to be MASSIVE with current solar technologies to get usable power after factoring in loss for transmission and conversion.

        Need more?

    • Re: (Score:2, Interesting)

      Though this is more about pie-in-the-sky this would be cool and inspiring stuff, practically, our best options right now are solar thermal power.

      Concentrated solar power uses no new materials-- glass, steel, mirrors, steam turbines, water, and occasionally fancy salts that we've already invented. It's one of the only renewable alternatives that doesn't want any money for research, just help getting some of the start up money to use materials we already have and make here in the US to build up these plants.

    • Well, if you assume the cost of getting the infrastructure up there is zero, space-based systems have some major advantages. There's more energy falling on the solar cells, and it spends almost all its time in full sunlight.

      The big drawbacks are the cost of installing and repairing, and the fact that it just cannot be done small. The microwave antennae are about a kilometer wide, so you have to hook up a lot of panels to justify that fixed cost.

      Still, once we have a heavy duty space elevator running, the

  • I don't know much about these things, but wouldn't it be possible to combine the Space Solar Power idea with the Large Mirror in Space idea to reduce global warming (or even initiate global cooling)? Or is this already been considered?
  • by Anonymous Coward

    I am a retired physicist/space scientist who researched this subject in the 1970s and again in the 1990s. While it is true that a huge amount of energy passes by and intercepts this planet, it was and remains too dangerous to try to get it down here for us to use.

    The idea was shelved back then for the simple reason that the number of launches needed to build the orbital facilities would completely destroy the ozone layer. (EVERY launch does damage to the upper atmosphere.) Funny, but the textbook of referen

  • A few lifetimes ago, I worked with Rick Tumlinson. Let me the first to say that anything he's put his hands into has a 100% chance of never happening. He's a nice enough fellow, but too all over the place to ever actually make anything turn into reality.

    I've never figured out *how* that foundation gets any money. I used to think that Rick was knocking over parking meters to meet the bills.

    But to be fair, he's still around, so maybe I'm totally wrong about him, but, I've heard him sing that easy access to sp

  • Project Orion.

    No, not the pansy thing using chemicals - the original where you blow yourself into space using nuclear bombs and pusher plates. No other way you'll ever get enough materials up there, not even enough to start a mining operation if you kicked a passing asteroid into high orbit. For that matter, there's no other way we can possibly establish a meaningful presence in space absent major breakthroughs in materials science and/or theoretical physics.

    By "meaningful," I mean space stations with
  • by victim ( 30647 ) on Saturday December 20, 2008 @09:08PM (#26187701)

    Whenever you read "spaced based solar power", just replace that with "municipal scale death ray". Now decide who should be in control of it.

    • by afxgrin ( 208686 )

      The power density would probably never be high enough to turn it into a death ray. Anything in the RF region would diverge terribly, and would need a multiple square km receiving array.

      The death ray concern is the least of the problems behind this idea. Lasers really are out of the question as well in my opinion. What's the point of converting laser light with photovoltiacs on the ground when we could just do that for the regular sunlight that we receive? In addition to that, the dc to laser power effic

      • Re: (Score:3, Insightful)

        by JoeMerchant ( 803320 )

        The power density would probably never be high enough to turn it into a death ray.

        A 1" magnifying glass can make solar death rays for ants... any multi giga watt system capable of transmitting that power to the ground in a useful form is going to be capable of frying stuff. It may be "completely harmless by design" - but with what this system is going to cost to build, I can't imagine it getting funded without a military application onboard.

        • Re: (Score:3, Interesting)

          by afxgrin ( 208686 )

          That's a poor analogy.

          You're putting all the light at a focal point. This would be the equivalent of having the lens too close to the ant, with it out of focus... the ant will just be rather bright.

          What I'm saying with the microwave beam is that you can't focus it that finely. Instead the system would be transmitting from many point sources, and the beam just can't be that easily focused without having a huuuuuge dish.

          One of the earlier proposals from the JPL was to use a phase-injected array of magnetrons

  • More energy equates to cheaper food, water, and transportation. I always thought we should cover the Earth in Solar before making our way into space and eventually creating a Dyson sphere. I'd be impressed if someone started this technology in my lifetime, let alone in this administration. I'm all about technology as a means to solving the world's poverty and disease problems. The easy solution to much of it is simply more energy.
  • How 'bout a large spherical object covered with solar cells and a dish antenna in the front to beam down the gigawatts of power. Say about the size of a "small moon".

Think of it! With VLSI we can pack 100 ENIACs in 1 sq. cm.!