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Science Technology

Lunar Power 588

An Anonymous Coward cites this article on ABC News, excerpting: "...the world would have access to a limitless power supply. The moon receives 13,000 terrawatts of power from the sun. Harnessing 1 percent of that energy, he calculates, could replace all fossil fuel power plants on Earth."
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Lunar Power

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  • By virtue of the size of earth, we ought to be getting more. Harnessing 1% of this is as good!

    S
    • by Anonymous Coward on Tuesday April 23, 2002 @01:41AM (#3392767)
      Yeah, except for that Ozone Layer, which has that whole 'filtering' ultraviolet light part, whereas the moon has no atmosphere.
      • by Begemot ( 38841 ) on Tuesday April 23, 2002 @02:28AM (#3392982)
        Don't worry, the brightest industry brains work on the ozone problem. It will be solved shortly and we'll get a whole lotta power right here.
        • Maybe that's what all this 'hole in the ozone' effort for the last 50 years has been about?

          Maybe 'the brightest industry brains' have already figured it out and are setting up solar arrays in Antartica as we speak? who knows? could be, hehehe...

      • What about the filtering effect of the earth's atmosphere upon microwaves transmitted to earth? Not to mention, what is the efficiency ratio, of collecting energy on the moon, changing it's form from solar to electrical to microwave, transmitting it 250,000 miles through space and earth's atmosphere, changing it again from microwave to useable electricity? What about having the microwaves aimed precisely at a target on earth without missing and 'microwaving' the wrong target (you or your neighbor)? Also 1% is a very nice cute little number, but guess what, if your talking 1% of the sunlight surface of the moon, you're talking a vast area. Especially if you want to cover that vast area with complex microwave transmitters, and solar panels. Mr. Criswell's thinking borders on the absurd, excuse me for being so negative, but why does he want to 'bury wires' from the solar panels to the microwave transmitters? The moon is so dead, the delicate footprints of Armstrong in the dust are probably still as they were in 1969. He states "90 percent of the aluminum, silicon and glass needed to build solar power plants can be found on the moon". Yes, true, but where are the foundries to smelt the aluminum from rock, the oxygen to burn fuel to melt silicon into glass, most importantly the human labor to make it all happen, as well as the food and fuel and tools to keep them alive and working? Seems like we should try it here on earth first. I could go on but Criswell displays such an exasperating level of naivete, that I wonder what drugs he took to become so excited about this, and how he even got a job at the University of Houston.
      • Yeah damm ozone layer!

        Can't we use FCKW gases to get effictivly rid of it? I think australia had already a ozone hole in the 80/90ies. Everybody get his spray cans and say no to the ozone layer :o)
    • True, but... (Score:4, Interesting)

      by BlackGriffen ( 521856 ) on Tuesday April 23, 2002 @02:57AM (#3393089)
      First of all, that darn atmosphere absorbs a lot of it. Second, that's the energy that keeps you warm and feeds you (plants don't live off of love, you know).

      The only way the moon as power source will be practicable will be if we move up there or figure out how to get that energy down here. Neither one is any easy task. You can pretty much forget about the first, and the second involves crazy plans with microwaves. What happens when the aiming device gets hit by a meteor, and the microwaves fry some poor shmuck? oops. Not to mention the amount of power that such a system would lose sending the signal through the atmosphere.

      The only way I see space based power being practicable is with some sort of geo-synchronous elevator (the ones that are connected to the planet by a metal cable in sci-fi). Then you could put solar panels, fission/fusion or pretty much any other type of power plant up there, and just let the wires carry it down with a whole lot less risk than a microwave beam.

      Don't hold your breath for any practicable space based power in our time, though.

      BlackGriffen
  • At What Cost? (Score:5, Insightful)

    by Galahad2 ( 517736 ) on Tuesday April 23, 2002 @01:39AM (#3392760) Homepage
    It currently costs $10,000 to get 1 lb of material into orbit. How much would it take to get it to the moon? One hell of a lot.

    It's going to be a heck of a lot cheaper to burn money to make power than use the moon for a long, long time.
    • uuh (Score:5, Insightful)

      by dmiller ( 581 ) <djm AT mindrot DOT org> on Tuesday April 23, 2002 @01:50AM (#3392819) Homepage
      You don't take photovoltaic cells to the moon, you build a factory on the moon and make the cells there. Just about everything you need is there: water [nasa.gov], minerals [ibiblio.org] and even some things that you don't find that often on Earth [asi.org].

      This is probably as far beyond our immediate capability as getting to the moon was to people of the 1940's - just a matter of time, money and will. The latter seems to be the most lacking.
      • Not just will but money as well!
      • You're absolutely right WRT how you'd actually do this. However, I remain unconvinced that, when compared to terrestrial solar cells, the smaller quantities of cells required outweigh the stupendous cost of setting up lunar production facilities and supporting the lunar staff to maintain the system.
      • by Ungrounded Lightning ( 62228 ) on Tuesday April 23, 2002 @03:38AM (#3393179) Journal
        You don't take photovoltaic cells to the moon, you build a factory on the moon and make the cells there.

        But why:

        use photovoltaic

        ship power back from the moon?

        This was examined back in the 70s and there's a set of even better solutions. Two samples:

        1) Put the actual collectors/generators in sync orbit:

        Much shorter distance to ship the power.

        Much greater surface area than the moon.

        Negligible gravity (just tidal and station-keeping forces).
        Alternatively: Use the L4 or L5 points - same distance from the Earth but still has the low-gravity and improved surface area factors.

        Mine the moon for the bulk of the material, but use a catapult to launch it to orbit. (For L5 there's an orbit using one of the other L points as a lens that requires very little delta-v to perform the final injection, so the catapult does essentially all the work.) Smelt and construct it in orbit.

        2) Build a STEAM plant on the ground and launch the pieces into sync orbit, where they're assembled. (Most of 'em go in reusable unmanned heavy-lifters. Much cheaper than the shuttle.)

        Steam has the advantage that you don't need to do a lot of fancy processing. Just a turbine, mirrors, pipes, generators, condensers (a flat plate painted black at right angles to the sun or behind the collector mirror, with some more plumbing attached), and a trick microwave transmitter (plus an antenna farm in the desert.) You don't need much water, and it goes around and around without leaking out for decades or more, like the freon (or whatever) in a household refrigerator.

        Tesla could have done it (except he'd have used VLF radio for the power feed, at considerable loss).

        These proposals and several others were examined in detail by the L5 society (founded by the same Keith Henson who is now in Canadian exile over the Scientology thing).

        NASA did a study on number 2, and came to the conclusion that it was too expensive. The L5 society then studied NASA's study and found an error: They'd done it in two steps:
        - Design a plant.
        - Design a set of vehicles to lift the parts.

        The heavy-lift vehicle was sized to lift the largest single part, which was the turbine wheel, which was enormous, making the vehicle very expensive. But it turns out it was enormous only because the plant designer had gone for efficiency with no thought to the launch issue. By sacrificing 10% efficiency the turbine could be reduced to the size of the next largest part, which would enable a much smaller and cheaper rocket to do the job.

        With the (unofficial) revised estimates, amortized over enough plants to feed the rate of growth of US power demand at the time, the total capital investment was a bit over a trillion bux. Sounds like a lot. But in fact it was cheaper than building any of the earthbound alternatives for the same capacity. (Fossil fuel and nuclear were both expensive - though nuclear wasn't yet politicized out of affordability - and the remaining options such as water, tidal, wind, biomass, etc. couldn't hack the demand.)

        Of course that's without even considering that the fuel is free.

    • It's going to be a heck of a lot cheaper to burn money to make power than use the moon for a long, long time.

      Why even make money to burn it? We can conserve our energy by not even manufacturing the crap and we'd save the trees.

      We could, however, burn cow manure and help to erradicate those ugly landscapes outside Area 51 where cattle was once raised that have been littered with pies. (Seriously, the area was big on cattle a while back)

      x
      • by x-empt ( 127761 ) on Tuesday April 23, 2002 @02:44AM (#3393051) Homepage
        On the cow manure idea:

        A new 750-kW power plant at Tinesdale Farms in Wrightstown, WI, is the first in the state to be powered by cow manure. The facility uses a "digester" to convert the manure to methane, which is then burned to generate electricity. Ag Environmental Solutions, LLC (Wrightstown, WI) owns and operates the facility, and Wisconsin Gas/Wisconsin Electric is buying the power and selling it to its customers. The manure comes from 1,800 cows at Tinesdale Farms, and it generates enough electricity to power 250 homes -- http://www.achrnews.com/.snippy./ [achrnews.com]
    • $0.02 (Score:3, Insightful)

      by 4of12 ( 97621 )

      It currently costs $10,000 to get 1 lb of material into orbit. How much would it take to get it to the moon? One hell of a lot.

      You're right, but as others point out, the big project would rely on an in situ photovoltaic panel factory on the lunar surface instead of transporting the panels.

      Nevertheless, I think it would be a good start to have a demonstration project, transporting and setting up earth-made panels on the moon just to see if we can beam some power back here.

      At the very least, it would get people thinking about the project and its problems and get it in the public eye, which is essential to get funding in a representative democracy.

      Just focussing people's minds on the problems is a good way to start solving them.

      If we dismiss this idea out-of-hand as too expensive and impractical, it is pretty well doomed to remain too expensive and impractical.

  • total nonsense. the receiving dishes would have to be large and would cost to much to manufacture and put in orbit. you'd be better off pursuing fussion as a source of energy. or why not build the solar cells on earth, or float them in lines of buoys on the ocean?
    • Ah, but imagine the new global economic return just in the number of jobs this would create.
      Rememeber that this would be akin to colonizing the moon and not just for curiosity's sake or 'research'. We've been looking for a viable commercial reason to do something like this and voila!
      Do you realize how much this would further the US's interest in developing countries... if we didn't have to build their power grid from scratch, we could hire all those work hungry people out there to do everything we don't want to do and for pennies on the dollar!
      I do care about people though and of course I'm thinking about the children and what a boon for them to have 24/7 access to teletubbies which would free up their mothers to join their husbands in the manufacturing plants.. all powered by the lunar energy consortium (or whatever) at very low rates, because when you have the whole world as your customer base you don't need to charge much individually. Better yet the energy could be bought nationally and redistributed by local carriers who could compete for customers, etc... sounds good to me.
    • by slackergod ( 37906 ) on Tuesday April 23, 2002 @01:52AM (#3392828) Homepage Journal
      Total nonsense?
      Sure, you could pursue fusion.
      But we may not get fusion. Should we wait
      for the PERFECT energy source while we rely on
      the bad ones, unstead of using a better one,
      while we pursue the goal of fusion, which
      (while theortically realizeable) doesn't even
      have a timetable associated w/ it?

      Furthermore, sure, the short-term costs would be
      large, but what are the costs for building and planning a new nuclear reactor?

      Solar cells on earth? We have clouds. We have day and night. The moon (thanks to an astronomical quirk) has permanent day and night. Much better
      efficiency that we can get. Store it there.
      Send it over, microwave style, when the terran
      receiver is in place.
      Or bounce it off a satellite.

      Just because you can conceive of better long term ideas, why should we not pursue a better short term idea, rather than stick to one that's actually harming us?

      -Slackergod
    • Speaking on the economical front, can you believe the terrorist threat from this if it were successfully implemented? Every first world country (AP/AU/EU/NA), given a few years, would adopt this technology for a complete energy solution. Since we currently receive much of our power from Middle Eastern countries who harvest the majority of the world's oil (and who, generally, aren't considered "first world"), this will only piss off the extremists (unfortunately, terrorist cells) loyal to those country's interests.

      If the lunar plan were to be adopted, I wonder what security measures would be implemented to protect this superior technology from those seeking to destroy it?
  • by swankypimp ( 542486 ) on Tuesday April 23, 2002 @01:42AM (#3392774) Homepage
    The generators would then convert the energy into harmless microwave beams, which would be aimed at collecting stations on Earth

    Apparently this dude has never put a marshmallow in his microwave oven.

    • Re:Harmless, my eye! (Score:5, Informative)

      by mindstrm ( 20013 ) on Tuesday April 23, 2002 @02:07AM (#3392878)
      I recall reading about this.
      If the beams are wide enough, they don't represent an immediate danger to anything passing through them.

      You microwave oven cooks so well because you have a 1000W output, in a contained space (say a cubic foot) reflecting around so most of the energy is absorbed by what you are heating.

      You also need to take into account what they mean by microwave. I think microwave is a general term for everything between 1Ghz and the visible spectrum. (1mm to 30cm wavelength)

      Your microwave oven operates typically on 2.4Ghz (yes, in the ISM band) (Yes, that's one reason the ISM band is license free, becuase it's dirty)

      At the appropriate wavelength, and over a wide enough area, the effects would be miniscule to anything but an appropriately tuned receiver.

      • You also need to take into account what they mean by microwave. I think microwave is a general term for everything between 1Ghz and the visible spectrum. (1mm to 30cm wavelength)

        Yes, let us a high energy form, with narrow wavelength, thats close to visible light, or even visible light. Now wait don't we already get this in masses for free from the sun? and not the moon. Why have we to hop ever the moon? Do you see the logical cludge?

        • Re:Harmless, my eye! (Score:5, Informative)

          by The Mayor ( 6048 ) on Tuesday April 23, 2002 @03:52AM (#3393215)
          Most of the Sun's energy is released between 225nm and 3200nm (UV, just outside visible spectrum, through IR, quite a bit farther oustide the visible spectrum). The upper atmosphere absorbs most frequencies up to about 320nm (thank you, ozone layer). The lower atmosphere (i.e. clouds, humidity) absorbs a great deal of the energy above about 1100 nm.

          The idea of having collectors on the moon is that on Earth the bulk of the Sun's spectrum is absorbed by the atmosphere. The moon has no atmosphere (ok, a negligble atmosphere). The entire spectrum can thus be collected, coverted to a narrow band frequency that has relatively low levels of absorption by the atmosphere, and beam it to Earth. Also, becuase the energy could be sent in a relatively narrow beam, the energy is easier to harnass without requiring sophisticated methods for focusing the beam (i.e. it's a lot easier to kill an ant with sunlight focused through a magnifying glass than it is to let unfocused sunlight to burn it).

          Actually, all you're doing is moving the focusing aparatus to the moon. But, on the moon, it gets to focus light that has not been filtered by the atmosphere. Thus, the resulting yield will be higher than if the same operation is conducted in the Sahara Desert.

          The concept makes perfect sense. It's not a logical kludge. However, I still have yet to see any sensitivity analysis conducted on the effects of adding additional energy to what is effectively a closed system. In other words, at least burning fossil fuels is harnassing energy already collected and stored by Earth. Adding energy that normally would not reach the Earth might force the system out of balance. Of course, the additional energy added to the system might be negligble compared to the energy transmitted directly to the Earth and the energy coming from our core (radioactive decay in our core? it's been a while...). I'm really curious to know how sensitive the Earth's system is to the addition of external energy sources.
          • by armb ( 5151 )
            > adding additional energy to what is effectively a closed system. In other words, at least burning fossil fuels is harnassing energy already collected and stored by Earth.

            The Earth is _not_ a closed system. The global temperature depends on an equilibrium between input energy and radiated energy. That's why greenhouse gases can raise the temperature. And the main concern with fossil fuels and global warming is CO2 being a greenhouse gas, not the actual heat dumped into the atmosphere by exhausts, cooling towers, etc..

            Burning fossil fuels releases energy stored hundreds of millions of years ago. There have been massive climate changes since then, and the fact that energy was once sunlight hitting the earth is completely irrelevent to the current balance.
            • by The Mayor ( 6048 ) on Tuesday April 23, 2002 @05:51AM (#3393461)
              Like I said, it is effectively a closed system.

              The amount of energy radiated from the Earth is part of the system. Adding extra energy that is normally received by the Moon adds energy to the system that would not normally be there.

              My point is that the Earth, as an effectivley closed system, has feedback systems that regulate the temperature. Yes, greenhouse gasses prevent the release of energy. However, historical sea level records (and other proxies for global temperatures) show that temperature fluctuations increase wildly immediately before ice ages. In fact, global temperatures increase several few degrees in a geologically short period of time (less than 1000 years) immediately before each ice age. This is one scientific argument behind people that claim we are not moving the Earth out of equilibrium (yes, some scientists are able to provide supporting evidence that we may be entering an ice age).

              Adding any external input to an effectively closed system *does* have an effect on the current equilibrium. My question isn't whether it has an effect (it does), but rather how great the effect is. The amount of greenhouse gasses we are currently releasing is trivial compared to the gasses released during enormous volcanic eruptions. That doesn't mean we should wantonly release greenhouse gasses. Instead, we should view our acts as external inputs that may affect the equilibrium (by contrast, volcanic eruptions are a part of the system). My question is, "What effects would occur if we consumed all our energy from a source that is external to the system?" This will undoubtably have an effect. The effect may be insignificant compared to the amount of energy released from the Earth's core due to radioactive decay. I don't know.

              If you have any evidence (supporting or contradicting), please let me know. But please don't give me pedantic definitions of a closed system that are irrelevant to the question at hand.
              • by armb ( 5151 )
                > The amount of energy radiated from the Earth is part of the system.

                Oh well in that case the answer is simple.
                Redefine your "effectively closed" system to include the Moon as well. Now transferring energy from the earth to the moon doesn't add anything to the system, just moves it about, so you don't have anything do worry about.

                > My point is that the Earth, as an effectivley closed system

                This isn't pedantry, you're just flat _wrong_. It's like saying "Microsoft Windows, as an effectively Open Source project".

                > Instead, we should view our acts as external inputs

                So last post fossil fuels were part of the system because they were formed on Earth, but now they are an external input?
    • by Ungrounded Lightning ( 62228 ) on Tuesday April 23, 2002 @03:56AM (#3393222) Journal
      The generators would then convert the energy into harmless microwave beams, which would be aimed at collecting stations on Earth

      Apparently this dude has never put a marshmallow in his microwave oven.

      You misunderstand the technology.

      The household microwave oven uses K-band microwaves. These were chosen because they're strongly absorbed by water, resulting in very efficient heating of most foods. (There are several ranges of frequencies that do that. But K band is absorbed about the right amount to cook food through rather than frying the surface or mostly passing right through.) Microwave ovens also have a very high energy density because the microwaves bounce back-and-forth and build up until they're absorbed by the food (or the transmitter magnetron, which is why they burn out if you run them too long when empty).

      The "microwaves" proposed for space solar power downlinks are MILIMETER waves - chosen because they're easy to handle and go RIGHT THROUGH water without being strongly absorbed. That's mostly so they'll go through humidity and clouds without major loss - though it helps that birds don't get cooked either.

      At the downlink rectenna farm the milimeter wave energy density is similar to the energy density of sunlight to maybe three times that. But the rectenna is MUCH more efficient than a solar panel at turning it into electricity. And the rectenna intercepts very little light. You can graze cattle under it.

      Even if there were an issue with the waves if they hit something ELSE (and for some stuff there is - it would heat up as if a heat lamp was shining on it), aim is not a problem. That's because the downliink is a synthetic-aperture system driven by a pilot beam from the rectenna site. The pilot signal is the only thing keeping the thousands of individual transmitters in phase. So if it's lost the beam defocusses. Most of it misses the planet entierly and the rest becomes nothing more than an annoying milimeter-band radio noise.
    • by millette ( 56354 ) <robin@@@millette...info> on Tuesday April 23, 2002 @05:48AM (#3393456) Homepage Journal
      Funny you should mention this. Did you know you can get an approximate figure of the speed of light using only a common microwave oven, marshmallows and a ruler? Try this experiment:
      http://www.physics.umd.edu/ripe/icpe/newsletters/n 34/marshmal.htm [umd.edu]
    • I know whats would happen... becuase i played sim city once.... big fires
  • Um... (Score:2, Informative)

    by Arrghman ( 172552 )
    Yeah, so uh what's so special about the moon exactly? Earth is practically the same distance from the Sun as the moon is distant from the Sun and isn't it a heck of a lot more efficient to just create a local satillite network instead of going all the way to the moon?

    Or even better... just have it based, I don't know, on the ground? Once we come up with more efficient solar cells then you're all set...
    • Re:Um... (Score:3, Interesting)

      by wadetemp ( 217315 )
      Yeah, so uh what's so special about the moon exactly?

      Yeah, strange why there is no life on the moon, isn't it? We have this cool thing (well, for a while, anyway) called an atmosphere. It kind of cuts down on the whole solar radiation thing so we don't, um, die. :)
    • WE have an atmosphere in the way, and as for satellites, a properly built system on the moon would be much more stable. We don't have to worry about keeping it in orbit, or, for that matter, blocking out our view of the sky.

      Collect energy on the moon, and beam it down here in some more efficient and less cluttering fashion.
  • 1%, ok, i'll grant him that...efficiency of solar cells being what they are..... of course that means completely covering the surface of the moon, and then figuring out a way to transport the energy back to the Earth....
  • Oh. My. God. (Score:4, Insightful)

    by Anonymous Coward on Tuesday April 23, 2002 @01:43AM (#3392786)
    The height of delusional techno-fantasy-masturbation. Come on people, let's think here. What's easier... Getting photovoltaic or thermal concentration arrays up into orbit at the cost of thousands of dollars per ounce and then shipping them to the moon, installing them, and somehow shipping back gigawatts of electricity to earth by radiation..

    OR,

    putting up photovoltaic or thermal concentration arrays on earth. On your house, your car, in the backyard, on fields, on buildings, on deserts, on woodlands, on fences, on anything that's flat, vertical, or in between, using unskilled labor and unsophisticated tools.

    The answer, of course, is to use less energy period. But you can't strap a nuclear warhead onto efficiency, so let's just go with the space rockets to the moon plan instead. Durr.

    • Re:Oh. My. God. (Score:5, Insightful)

      by greenius ( 300851 ) <<ku.oc.suineerg> <ta> <nevets>> on Tuesday April 23, 2002 @08:09AM (#3393737) Homepage Journal
      > The answer, of course, is to use less energy period

      Using less energy is not a solution.

      The future of humans can not survive by staying on earth. The only way to get to the next level of development required for interplanetary and insterstella travel will require huge amounts of energy compared to what we have on Earth. The sun is pumping out loads of wasted energy into space. The sooner we can start the technology development to grab some of this energy then the sooner we can expand off this planet and increase our chances of survival.
  • by Zara2 ( 160595 ) on Tuesday April 23, 2002 @01:45AM (#3392797)
    ABC.com and Slashdot both put up a story from a wacko. News at 11.

    C'mon editors. My cat could have figured out a better power scheme than this. Even the Hydrogren that is 20KM under the surface of the earth would be cheaper. New national level building codes where we force all new buildings to have solar panel roof tiles and solar colleting windows would be easier to pass by congress. Also, quite frankly, the guys that are still hacking away at cold fusion probably have a better chance of getting it all to work.

    Damn I wish this was K5 so I could vote to dump this article.

  • Physicists do not know much about economics.
  • by SecretAsianMan ( 45389 ) on Tuesday April 23, 2002 @01:52AM (#3392826) Homepage
    ... a limitless power supply. The moon receives 13,000 terrawatts ...
    Gosh darn it, that sounds like a limit to me.
  • Everything posted before this seems to knock this idea.

    Granted it's not the best - people are letting other current problems stand in the way.

    So, let's recap:

    Lower the cost of getting things in orbit.
    Make better working solar cells.
    Costs too much [for whatever other reason].

    Of course we could change these things. If my local power plant could take in some money for investing in such a crazy system we might actually see something like it.

    Maybe it would be better for other situations like storing emergency power or making batteries for space craft....
  • Whay happens when there's a cloudy day on earth - which is more often than not...
    Anyway - some of that energy will leak into the atmosphere and will result in heating of it.
    Other problems - How about jets trying to avoid the wandering microwave beam paths - unless we we can somehow narrow down the beam to an incredibly tight small area. This seems unlikely to be able to get this sort of precise control.

    I swear we've seen this idea multiple times before on slashdot...
    • Do you know how many wind/solar power system exist, and are relied upon to provide power 24x7?
      Tons. They use battery's, it stores energy for times when there is a "cloudy day". And as for the jets we could develop system of side thrusters that move it out of harms way. We can use GPS to triangulate the position of the planes and the exact amount of thrust required. This could be handled automatically by a computer........ that was a joke.
    • Whay happens when there's a cloudy day on earth
      It won't be a problem - just bump up the intensity of the beam and boil those pesky clouds away.

      Telsa gave up on broadcast power a century ago due to the inefficiency, and while microwaves can be more closely focused the loss would still be enormous - particularly with some water in the air. Huge dishes may be an answer, but an expensive one.

      Anyway - some of that energy will leak into the atmosphere and will result in heating of it.
      Some energy will get lost that way if there is any moisture in the air.
      How about jets trying to avoid the wandering microwave beam paths
      It would depend upon the intensity, the skin of most aircraft would act as a faraday sheild (the pilot may still get fried). Birds and people in the wrong spot would not come equipt with faraday sheilds.
  • Quoth the caption:
    A U.S. soldier scans the horizon as the moon rises behind him in Kandahar, Afghanistan. A physicist claims solar energy reflected from the moon could provide endless clean energy

    Do they just have stock footage of Afghanistan lying around? Is this the best moon picture they could come up with?

    Maybe they just searched through the pictures lying on their desk, till they found one with the moon in it. We're lucky we didn't get a snap-shot of the author's poodle with the moon in the background.
  • by Peridriga ( 308995 ) on Tuesday April 23, 2002 @02:13AM (#3392912)
    Microwave Power?...

    Sim City 2000 Anyone?...

    Where the hell are my Arcologies?
  • ...would have to be a no-fly zone. Come to think of it, it'd have to be a no-pigeon, no-duck, no-eagle and no-butterfly zone too.

    I don't think any of these uwave links will ever get built for one reason: NIMBY. (Not In My Back Yard).

    Now, maybe you could convince some desparate 3rd world nation to receive, but that's not where the power is needed now is it? So you would just compound the transmission problem. I think they are better off using the power right there on the moon to drive energy-intensive manufacturing processes that produce small products that can be easily shipped back to Earth. That way, you free up energy resources on Earth without having to fuss about how the power is transmitted. Synthetic diamond production perhaps? Then of course there is the potential of mining the moon and running electric smelters up there, but it's probably only practical for certain rare commodity metals. How much platinum and gold is on the moon?

    • Microwave beams? Is that really much more effektive than "light" beams that exist just at a bit lower frequency, and are pretty harmless. Yes let us transmit the energy in form from light beams to earth. Okay? Hey wait, we have already an astronomical object like this that does that freely, so why not just catch them directly from the sun?
  • Harnessing 1 percent of that energy, he calculates, could replace all fossil fuel power plants on Earth."

    The actual quote said, "Harnessing 1 percent of that energy, he calculates, could power up to four Intel Pentium-4 processors AT ONCE!"
  • Should we use the moon for our power needs, or...

    should we BLOW UP [cc.mi.us] the moon [hbdub.com]
  • "The moon receives 13,000 terrawatts of power from the sun... (bla bla)"

    Why on Earth (pun intended) would we need to go the Moon for this?

    Doesn't Earth get a healthy amount of energy from the sun as well? Would be surprising if it didn't. Clouds? They aren't that big of a problem. First, they don't cover 100% of the solar rays. Second, if the cells cover 1% of Earth's surface, that would be enough to get continuous energy IMHO. And, of course, you'd like to place most in sunny areas like deserts.

    The big problem is to make effecient solar cells that cover 1% of Earth's surface. A pretty big area indeed. And make everyone agree with that it's ok. But I guess it would still be easier than going to the Moon for this.

    Also, who's gonna pay?
  • Bad Math (Score:4, Interesting)

    by The Raven ( 30575 ) on Tuesday April 23, 2002 @02:19AM (#3392952) Homepage
    So, the moon receives 13000TW of power, and we only need 1% of that? Let's do a little math eh...

    Solar cells are at best about 20% efficient. For the sake of my argument, that's the number I'm using. The argument stands even if you could imagine getting 50% efficiency from the falling sunlight.

    They would need to cover 1% of the lunar surface on BOTH sides of the moon, because only half of the solar panels would be in sunlight at a time.

    They would need to cover 5% of the surface, because the cells are only 20% efficient.

    Combine those two problems, and you have 10% of the surface of the moon covered in solar panels. Add another 5% because not every portion of the surface is suitable for placing panels. Multiply the result (15% of the lunar surface covered) by about 1.5, to make up for the transmission loss from the moon to earth, and through the atmosphere. Result... over 20% of the moons surface, its TOTAL surface both visible and non, covered with solar panels to get that 130TW the author stated.

    Imagine the moon with a bright shiny ring of solar sails all along the left and right edge. If you can't hear every environmentalist and presevationist crying out simultaneously in anger, you are deaf.
  • The efficiency of the current photovoltaic cells is only 10%. To harness one percent of the energy received by the moon would mean to cover 10% of its surface.

    Sure.

    Even a Dyson sphere seems more realistic :)

    The Raven.

  • Imagine how much energy must be shining on the Earth. Maybe we could harness that. Wait...
  • First - covering a big portion of the surface, which is going to be in the dark half of the time.

    Second - getting the energy to where it will be used. This isn't particularly silly, since the energy could be used to manufacture something on the lunar surface (eg. satellites) which doesn't need to go all of the way home. Manufacturing processes like vapour deposition would work well there on an enormous scale - but at current scales it is a lot easier to use vacuum pumps.

  • Now the problem comes in ... Earth is rotating. The moon isn't in an equatorially geosynchronous orbit and eventually either the receiving dishes would need to be moved or the transmitting dish on the moon would transmit enough microwaves to eliminate life as we know it for a few hundred meters around its target. If you fear the cellular phone radio waves.... think sticking your head into your microwave in the morning instead of coffee.

    People have discussed the idea of transmitting power before. Heck, Russia built a solar reflector to light up their northern lands. It's feasible, but being able to protect Earth from a microwave disaster would be EXTREMELY hard.
  • Um hello to all the fuckheads at ABC: If the moon receives that much energy, and the Earth is 10x (or whatever) bigger than the moon, I'd bet it receives more energy from the sun (even accounting for all that is scattered by the atmosphere) and would be just a wee bit easier to capture. Let NASA spends it's billions (oh wait, Bush is in office...) on important stuff, like say that little project that is billions overbudget right now.
  • And imagine what a mega weapon a moon covered with solar cells is. Just send the amazing energy as non-"harmless" to your country of favorite hate.

    Man I'm happy this project is technically impossible, and don't tell me US army wouldn't have thought of that use of such an installation.

  • "Greetings, my friends. We are all interested in the future, for that is where you and I are going to spend the rest of our lives. And remember, my friends, future events such as these will affect you in the future."

    -- Criswell, Plan 9 from Outer Space

    Schwab



  • "...the world would have access to a limitless power supply. The moon receives 13,000 terrawatts of power from the sun. Harnessing 1 percent of that energy, he calculates, could replace all fossil fuel power plants on Earth."

    If we've got the same guy doing the calculating as we have doing the spell-checking, we're fucked. Besides, duh, it costs money to get something to the moon. Whats the rocket going to be powered by? Cash or rubberbands?

    Cheers,
  • There was a NASA summer study around 1980 at which this was proposed. To bring it off, it's necessary to build autonomous construction robots. Back in 1980, the robot crowd was confident they'd be able to do it on the moon by 2000. My comment, to one of the enthusiasts afterwards, was, "When will you be able to do it in Arizona?"

    If we had the technology to do this on the moon, we could do it more easily on some desert.

  • One Percent (Score:4, Informative)

    by LastToKnow ( 449735 ) on Tuesday April 23, 2002 @03:24AM (#3393150) Homepage
    Just for kicks and giggles, I thought I'd try to figure out how much area you'd need to cover to pick up that 1% of energy hitting the moon.

    Radius of the moon [nasa.gov]: 6378.1 km

    So the area of a disc of that radius is 1.278e8 km^2.

    One percent of that is of course 1.278e6 km^2.

    Lets construct our solar panels in a band around the equator, so that at any given time, 1% of the sunlight is being collected.

    Treating the band as approximately a rectanle, so I don't have to think too hard, 1.278e6/6378.1 = 100.18 km

    Now this stripe on a flat disc needs to be translated back to a band on the surface of a shpere. Approximating that band as a cylender, with hight 100.18km, and radius as that of the moon, we get approximately 4.0e6 km^2. For reference, thats tad less than half the size of the United States (9.629e6 km^2).
  • by blair1q ( 305137 ) on Tuesday April 23, 2002 @03:29AM (#3393162) Journal
    Build several (or several hundred) big (square-mile-plus) mirror-array collectors throughout the world (the dispersal reduces output fluctuation due to nightfall and weather).

    Use the concentrated sunlight to generate steam which generates electricity which can be transmitted to grid subscribers, or to wet areas to generate hydrogen from easily available water (they hydrogen storage further reduces output fluctuations by acting as a chemical battery).

    Use the hydrogen to run vehicles, electric generators for off-grid communities, and grid generators when sunlight is scarce.

    The startup costs for this can't be any higher than for exploration, drilling, and refining of oil in the millions of wells we've sunk, and the resource costs aren't any lower than free gunk from the ground, and the maintenance can't be nearly as expensive as tankers and oil slicks, so this should work out fine until the sun quits on us.

    --Blair
  • One way I could imagine the government and maybe even the industry barons accepting this idea is if the power plants could essentially build themselves. The article doesn't say so but I'm sure Criswell's plan includes robotic construction equipment. Instead of sending up machines to build the power plant, how about sending up generic machines that build other machines that eventually build the machines that build the plant. The design strategy would be to work backwards from the finished product to something as cheap and simple as possible that could be built and launched right now. Getting something cheap up there soon and giving it a few decades to evolve might be easier than spending decades begging for funding.
  • Wow, the Moon recieves 13,000 terawatts of power from the Sun, whoopdy-farking-doo. The [b]Earth[/b] recieves 100,000+ terawatts of power from the Sun.
  • Haiku (Score:3, Funny)

    by petis ( 139263 ) on Tuesday April 23, 2002 @04:00AM (#3393230)
    Energy schemes
    from another lunatic
    remember Enron?

    :-)
  • Make sure one of those things is on the far side of the moon, and the other as close to it as it can be and still work the way it is supposed to.
  • by gnovos ( 447128 ) <gnovos@ c h i p p e d . net> on Tuesday April 23, 2002 @04:35AM (#3393308) Homepage Journal
    The ONLY reason to use the moon is becuase it has cheap materials. Build your solar collectors (preferably solar lasers and whatnot) on the moon and lauch them towards mercury. The sun puts out more energy in a single week than has ever existed in ALL the reserves of wood, coal, gas, oil and nuclear fuel on the earth... combined. That is a frigging lot of free god damned power out there!
  • Great - now all we need is a 385,000km cable to attach to it... oh and to shift the moon into a geo-stationary orbit so that the cable doesn't end up getting tangled - dang...
  • Perspective (Score:2, Interesting)

    by Tranvisor ( 250175 )
    This guy says it can be done for 135 billion. Thats alot of money, but lets just put this in perspective. Lets say the project goes over budget by say 20 percent (as alot of space programs tend to do) and ends up costing in the neighborhood of around 160bill. Damn thats alot of cash!

    Then wrap your mind around this. Our government spent 60 billion to design and buy the latest and best fighter jet the F-22. Our military budget is $68 billion a year and expected to jump to $100 billion in the next four years. And you guys all think that this guy's idea is to expensive? If he has done the groundwork on the project enough to come up with a estimate, and ABC put up a story about it I would hope that we can at least believe his estimate.

    $135 billion is chump change when you think about what would be accomplished. It could be a marvel of human genius. And perhaps it might make the world think a little better of us if we started producing all the power we actually used, while selling it cheap to them to.
  • Criswell believes lunar solar panels are more practical since they wouldn't be adding to the already accumulating level of debris in space.

    He's worried about debris orbiting around the Earth, when his proposal involves potentially tearing up the moon's surface.

    Still...the idea has some merit, just seems a bit crazy.

  • Seems to me it doesn't matter what they're doing up there, as long as they _are_ out there.

    Where are the lunar-hotels we've been promissed? When will I be able to take a vacation on the moon?

    I'm pretty sure that once we start building something up there, whatever is might be, we'll have to come up with new technologies, new ideas, etc.

    When was the last time a man stepped on the moon? Space exploration nearly came to full stop in the past decade. All we do today is luanch more settalites -- can you say space junk -- and work on that ISS, which only hell knows when will become operational.

    Sure, it's a stupid method of generating power, but if it involes going back to space, I'm all for it.

  • A better idea that's technically not much less umptuous. Why leave it at the moon? We can build a huge spaceship travel to Alpha Centaury (our nearest star) and then build a sphere right around the star catching *all* it's light. Then send it as a "harmless "microwave to earth, and hope that earth doesn't just evaporate from all the energy.
  • Dr. Evil may try to take it over, and ask for $1,000,000 - wait, $100,000,000, to prevent the barbecuing of NY State......

    Do you expect me to talk?

    Nooooo Mr. Bond, I expect you to die.....
  • WTF is a terrawatt? (Score:3, Interesting)

    by jpellino ( 202698 ) on Tuesday April 23, 2002 @10:32AM (#3394472)
    If it's a goof - frag'em.
    (I know - we all mis-spell, but this is a Big Deal Scientist and this article made it past a science writer and an editor, eh?)

    If it's a pun- frag'em then frag the fragments.

    We'll give the author and the researcher the houses right next to the microwave receivers so they can then deal with the inherent problems in controlling a 240,000 mile long MASER beam when there's a 2+ second lag in your feedback loop for aiming those TERAwatts back to a constantly moving hand-off receiver network. (the moon may always show the same face to the earth, but it don't work the other way around - no spot on earth can see the moon all day - and for much of THAT time the geometry sucks)

    OK - so go to a TDRS type satellite network - geostationary final leg - then tell me that it's more efficient to develop a microwave receiver farm from scratch (rectennas still only exist as science-fair-sized demos - this is like launching an estes Big Bertha then asking NASA to let you build the next gen shuttle...) than to just ramp up production on terrestrial PV cells?

    The original PV geosynchronous satellite plan (Glaser et. al.,) is still too expensive to be implemented - and that would just be the final leg - imagine getting a manufacturing plant to the moon! We only put 16 tons of stuff on the moon six (ok we tried a 7th) times. And that was just to scott around for a weekend.

    We're already getting upwards of a kilowatt-hour per square meter in most places on earth that need it - why not use what's here?
  • by apsmith ( 17989 ) on Tuesday April 23, 2002 @11:14AM (#3394784) Homepage
    Somehow nobody has yet linked to Criswell's original article [aip.org], which was published in the current issue of the Industrial Physicist [aip.org], put out by the American Institute of Physics, a highly respected research physics organization in the US.

    In other words, Criswell is no crackpot; this is a realistic plan. Read the article. I don't entirely agree with him - I think lunar materials could more effectively be used to construct orbiting solar power satellites - launch from the lunar surface can be very cheap using electromagnetic railgun technology, and in orbit you can get sunlight 100% of the time, not 50% (with solar incidence angle effects to worry about too). But Criswell's scheme is one of the most promising options, and should be considered seriously.

    How soon could this be done? Essentially all the technology is in place - the scheme could benefit from some further developments of robotics, but a first launch date of 2010 is not unrealistic, and we could have power from the Moon before we would see anything from ANWR :-)
    • Since it's still way too expensive to even assemble and use geosync. PV satellites as described by Glaser et. al., then how could it ever be productive to launch something just as large to sit there and RELAY power coming from another more expsnsive installation 240,000 miles away? It's not.

      Once upon a time we made ourrsleves believe that we could build lots of safe, effective, cheap nuclear power plants. In theory - yes. Practically - no. Why? Becasue when you look at things as a physicist, anything within the bounds of the laws of physics can be classified as a good idea. Hand it to an engineer, and you run up against a whole new set of limits that fall into the category of 'practical'. Then try to sell it to the public, and you have to address the realistic needs and wants of real people who you were supposed to be helping in the first place.

      Please remember that our largest excursion series to the moon - Apollo - simply moved about 100 tons of equipment (16 tons six times) - and that was just to tool around for a few days each time. This power plan entails mining, smelting, metals purification, HIGH PRECISION manufacturing (you esssentially have to build a semiconductor factory to make PVs), etc... it's one thing to ask people to assemble fully debugged building blocks on Station, and if we can do that. why bother launching it to the moon?

      And how you gonna get that much-ballyhooed railgun in place and working on the moon? They are another high precision, high maintenance piece of work. The Lunar Module Ascent Stage engines had exactly two working parts and a backup for each, and talk to the moon walkers about how much sweating they did over that simple little detail. I've seen a simple testbed railgun (firing mere bricks) go south, and would not want to be nearby in an EVA suit when it happens. There are far more practical details to doing this than the theory suggests.

      I envision many large boxes marked "ACME" whenever people start spouting things like "get a railgun" , "go to the moon", "shoot stuff back". I spoke with Gerry O'Neill about these schemes several times when he was still with us - and while I admired him as a visionary, you still have to place all these use-the-moon schemes as Velikofsky in the 40s. Yes, it eventually worked. Yes, it was exciting. Is anyone going to the moon since for any practical reasons? No. Were there valuable spin-offs? Many. But no-one at NASA ever deluded themselves into thinking that the Apollo missions were worth billions of dollars as a geology field trip. And no one will go to the moon to build power stations simply because we need energy. We have energy. We need a better financial model and a better distribution network.

He has not acquired a fortune; the fortune has acquired him. -- Bion

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