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Power Science

Harnessing High Altitude Wind Power 132

Posted by CowboyNeal from the just-a-lot-of-air dept.
jakosc writes "The Economist has an interesting article about increasing the efficiency of wind-powered generators by turning them into flying wind farms. These tethered generators would harness high speed jet stream winds above 15,000 ft and in theory could give outputs of 40MW per generator (PDF). The developer's website has more details of some of the safety, technological, and economic issues."
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Harnessing High Altitude Wind Power More

Harnessing High Altitude Wind Power

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  • Dupe. (Score:5, Interesting)

    by frakir ( 760204 ) on Saturday April 14, 2007 @10:56AM (#18731995)
    Not only is this a dupe (http://science.slashdot.org/article.pl?sid=07/04/ 04/2142232 [slashdot.org]) but there are much better ideas.
    Check http://www.magenn.com/ [magenn.com] for example. And much less dangerous.
    • I had a feeling of being in a time loop until you pointed that old article out :)

    • Re: (Score:3)

      by caseih ( 160668 )
      And you are an expert in this field? Don't be so quick to discount any one idea. Rest assured (dupe notwithstanding), the obvious negatives of this proposal have not been missed by people behind this idea. Frankly the generating idea of magenn.com is not even close to what Sky WindPower is exploring. In the short term, yes mangenn.com's tethered generators are much more practical, so I'd like to see people put them to use, as they are more efficient than a conventional turbine. But in the long term the

      • Re:Dupe. (Score:5, Interesting)

        by florescent_beige ( 608235 ) on Saturday April 14, 2007 @01:20PM (#18733279) Journal

        I'm happen to be an expert in aircraft structures and based on what I said [slashdot.org] in the original thread, I really wonder if they know what they are talking about. The Economist article talks about aluminum tethers and from what I can tell such cables would be physically impossible. That is basic stuff to get wrong.

        Secondly, a winged platform with horizontal-axis turbines would make more sense. Their helicopter-ish layout uses a lot of rotor structure to present a little area to the airflow. You cannot tilt the platform to present more rotor area to the airflow because the lift vector has to be parallel to the anchor cables where they attach to the vehicle. Those cables which will be nearly vertical, that is basic catenary physics and there is nothing you can do about it unless you use other lift vehicles to hold the tether up (the way high-altitude kites work.)

        Thirdly, the jet stream meanders around. Are they thinking about moving the turbines to follow the jet stream? How would that work? Would they move their restricted airspace region to follow them? And what kind of ground station would be massive enough to bear the large forces this thing generates and be portable enough to drive on roads?

        Fourthly, it will have either be certified by the FAA or will have to fly over uninhabited areas. Flying things crash, they always crash, and a 10 kilometer cable whipping down on you from the sky is a nasty thought. Certification has killed more than a few projects that otherwise seemed like good ideas.

        I'm not saying it's all impossible. Just unlikely.

        • Re: (Score:2)

          by Prune ( 557140 )
          You can weave aluminum threads into a rope of a different material that provides the needed tensile strength and flexibility.

          • This is true, I did some calculations on the other thread that showed aluminum probably couldn't be made to work and graphite probably could. The property you need is a high tensile strength/density ratio. Kevlar and Specta also have very high ratios, so they could be used as the load carrying reinforcement.

            The advantage of graphite is that it is conductive and could maybe be used as the conductor too so you wouldn't need the aluminum. That would add risk to the project because it may never have be done b

            • Re: (Score:3, Informative)

              by Prune ( 557140 )
              Aluminum: 26.50 nm and 2.70 gcm3 Graphite: 9.8 - 41 m and 2.09-2.23 g/cm So at similar densities, graphite's an order of magnitude more resistant. A cable without metal conductor is not practical here. The aluminum component is a must.

              • Re: (Score:2)

                by Prune ( 557140 )
                Fucking hell, forgot this is HTML and it wrecked the nice unicode characters. The 9.8-41 figure for graphite is supposed to be microOhm-meters, and the 26.50 for aluminum is nanoOhm-meters.

                • Re: (Score:2)

                  by Prune ( 557140 )
                  Moreover, it's a three orders of magnitude difference, not one.

                  • Re: (Score:3, Informative)

                    by florescent_beige ( 608235 )

                    The resistivity of graphite fibers varies quite a bit. For example the venerable Toray T300 fibers are listed around 2000 microohms-cm, while Union Carbide P100's are around 250. You have to be careful because bulk carbon is different. Aluminum is about 2.7 in those units. Graphite can be specially made to have lower resistivity but I'll use the 250 value for ROM calcs. Use a 16km cable length.

                    So if we assume a 1 in^2 cable section (6 cm^2) and they can manage to get 15kV, the current for 40MW is 2667A. T

                    • Just for posterity's sake, I knew something was wrong with para 5.

                      The formula for energy density should be E=1/2mV^2=1/2*rho*V*V^2=rho/2*V^3 so the wind speed would be V=(20000/.4)^.333=36 m/s (132 kph). That makes more sense.

                      So energy density goes with the cube not the square of wind speed. The speed of the airflow on the back side of the turbine will be Vf=36/2^.333=28 m/s. Force per unit turbine area is F=.4*36*(36-28)=115.2N and Ftot=115.2*4000=460800N (103000 lbs).

                      So in terms of the forces involved

      • Re: (Score:3, Informative)

        by kimvette ( 919543 )
        I'm more concerned about this development further endangering general aviation, on top of the states trying to tax private pilots to death.

    • Re: (Score:1)

      by chtank ( 83512 )
      All of the proposals have merit and need research. I suggest, however, that we do it with knowldge of what is being reserached now. The best sources for gathering all the research together is linked here:
      http://www.eere.energy.gov/ [energy.gov]
      http://www.epa.gov/climatechange/ [epa.gov]
      http://www.nano.gov/ [nano.gov]
      Yes, our government is working on the problem(s), if budget cuts don't go too far, this is one place where our Tax money is well spent.
    • Yeah I like their idea more... my first thought when seeing flying turbines was of a giant wind-sock with turbines down the centerline... this MARS thing looks close to that. Keep it aloft with a balloon and you're set... I can see a whole new set of windfarms like this... just a big tethered together set of wind-sock/turbines waving in the jetstream cranking out energy

    • Re: (Score:1)

      by Xanius ( 955737 )
      I think we should just get it over with and start with the geothermal drilling platforms. They seem to go over well in all of the scifi movies and shows.

  • maybe not... (Score:4, Insightful)

    by nanosquid ( 1074949 ) on Saturday April 14, 2007 @10:58AM (#18732013)
    Taking out 40MW of wind energy per wind farm from high altitude winds may not be such a good idea; that energy is doing something right now: mixing the atmosphere, generating heat, etc., and chances are that whatever it is doing is probably important for keeping the atmosphere the way we know and like it.
    • I also wonder on the reduced volume of air and how that would effect the energy production at that altitude.

    • Re: (Score:1, Insightful)

      by laggist ( 784355 )
      don't think it impacts in such a way - the system (practically) passively extracts energy from the winds isn't it? it's not like the tides don't come in anymore when we put in wave based generators on the coastlines

    • Re: (Score:1)

      by Joffy ( 905928 )
      I believe your point is valid, but the percentage of energy you are taking out of the wind currents should be so small the effect would not be recognizeable. Now thats for one of them. I'm not sure how many you need given a certain area.

      • At 80m, it's about 70 TW. So to make one percent, you'd need around 20000 of them at 40MW. On the bright side, that would be about 0.8TW, or almost half of the current electricity consumption of the human world..

        At higher altitudes (which this is), the energy is somewhat higher, I understand.

        Total energy from the sun is somewhere around 170.000 TW, if I recall correctly.

        • You're implicitly assuming that 1% or 0.1% or whatever is a "small number", but there is no way of predicting that. Furthermore, you're calculating the percetage based on total wind energy, but these devices can extract energy only from a particular kind of flow, hence the percentage of energy removed from those kinds of flows will be much larger.

          Nobody can predict what the effect of a widespread deployment of such devices would be, and we need to be quite careful not to rush into another "quick fix" soluti

          • I was merely putting out numbers and putting them in perspective. I did not mean to imply anything. I'll let the scientist do the impact calculations, I'm not qualified for that at all.

            It might interest you to know, though, that the 70TW is supposed to be available for windpower at 80m, not total wind energy at that level. So for total windpower, the number is much too small; from what I've read, total earth window is in the 1e16W range (but I am not really sure on that one).

            I do not agree that there is "

            • I was merely putting out numbers and putting them in perspective.

              Well, and what perspective would that be?

              I did not mean to imply anything.

              Sure you did.

              It might interest you to know, though, that the 70TW is supposed to be available for windpower at 80m, not total wind energy at that level. So for total windpower, the number is much too small;

              Those numbers are just as irrelevant as your previous numbers. These devices don't randomly capture wind energy out of the total wind energy, they capture one specifi

              • I was merely putting out numbers and putting them in perspective.

                Well, and what perspective would that be?

                I did not mean to imply anything.

                Sure you did.

                You seem to be in denial of reality, and I have no time for religious types. PLONK.

        • I think we can make up for that by building aerodynamical houses and buildings. And we made up for it already by removing a hell of a lot of trees.

          • I think we can make up for that by building aerodynamical houses and buildings.
            I'm as much in favor of green technology as the next guy, but there's no way I'm attaching my house to an aluminum tether and relocating into the middle of the jetstream!

    • Re: (Score:3, Informative)

      by maxume ( 22995 )
      The wind is a side effect of the atmosphere mixing. If you calculate the total amount of energy from the sun, the current human consumption of ~12 terawatts is considerably less than 1%. It's probably big enough to pay attention to, but as long as you bring the farms online a few at a time, you aren't going to do any sort of long term damage.

      (sunlight reaches the earth at a rate of about 1300 W/m^2; model the earth as a big disk with a radius of ~6,000,000 meters; 1300*3.14*6000000^2 = 1.45*10^17 watts; 1 t

      • Moving target (Score:4, Insightful)

        by mangu ( 126918 ) on Saturday April 14, 2007 @01:12PM (#18733209)
        the current human consumption of ~12 terawatts is considerably less than 1%


        If the discussion were about substituting current consumption only, I would agree wholeheartedly. But first, we are talking about a growing number of people, and second, most of these people would like a better standard of living, which means a higher energy consumption.


        If the rest of the world had the same standard of living as the upper middle class of the USA, the world would consume at least ten times more energy than it does today. Any discussion about alternate energy sources must consider that we need a supply that's much bigger than the current level.


        And let's not get lost in that "reducing usage" argument. A considerable fraction of mankind today has such subhuman energy consumption level that's impossible to reduce it further, no matter how efficient you get. Yes, by all means, let the rich Americans share subcompacts instead of each driving an SUV, but there's very little that the peasant that walks from his hut to his field which he digs with a hoe and a shovel can do to reduce energy use. And these are the majority of the people in the world, we must both increase energy production *and* use it more efficiently at the same time.

        • Re: (Score:1)

          by maxume ( 22995 )
          Consider my ballpark figure. 1000 TW is still only ~0.7% of the solar energy striking the atmosphere(it gets a lot messier when you start counting ground level energy that you can harness, but 50 or 100 TW is probably doable). But that wasn't the point. The point was that there is so much energy being pumped around in the atmosphere that you can bring one or ten of these things online with basically zero risk of causing a persistent problem; you might find out that you want to turn it off right away, but on

        • Re: (Score:2)

          by Anderlan ( 17286 )

          I wouldn't immediately say that we couldn't increase standard of living while remaining at the same power consumption level. There are 300M Americans, thats 5% of the population. I am not prepared to state that technology couldn't enable the same amount of useful work that is done by devices in a 2kW (average) household to be done with just 200W. Many devices are hugely inefficient and badly designed.

          I only *just barely* agree with your thesis that development without increased energy output at the sourc

      • These devices don't remove wind energy uniformly across the whole globe, they remove one very specific kind of wind energy at a narrow range of altitudes over a specific range of terrains. Dismissing concerns, as the authors do, by saying that it is "not expect to have adverse environmental consequences" is hardly sufficient.

        I'm not saying that we shouldn't explore these options, but with future energy options, we should study the environmental impact a lot more carefully ahead of time than we did for coal

        • Re: (Score:1)

          by maxume ( 22995 )
          It's not the 'wrong' calculation, it just isn't very specific. The energy in the atmosphere is nearly wholly solar in origin, so looking at the size of that particular input gives you a window into the magnitudes involved. Out of the 145,000 terawatts, it is reasonable to assume, it really is(basically because weather can be described in terms of energy moving around), that you can extract a few megawatts without causing any problems. Hurricanes 'extract' many gigawatts of power from the atmosphere and gene
    • Taking out 40MW of wind energy per wind farm from high altitude winds may not be such a good idea; that energy is doing something right now: mixing the atmosphere, generating heat, etc.

      Just consider it a small cooling effect to offset the warming effect generated by Cow methane.
      • Just consider it a small cooling effect to offset the warming effect generated by Cow methane.

        Trouble is that cow methane is causing problems at ground level; taking energy out of the atmosphere at high levels could easily make global warming worse.

    • Re: (Score:3, Interesting)

      by Oriumpor ( 446718 )
      Because this argument was prevelant the last time this was posted. (read: dupe, dupe,dupe, editors wake up, it's another dupe.) I'll repost the rebuttal: the energy removed from the slipstream is estimated at 1/10th of 1 percent if the entire planet were to be powered by these devices.

      And to reiterate my rebuttal in the last dupe: The energy removed from the atmosphere when the planet's coal plants were disabled might far overshadow the energy harnessed and reused...

      Wind energy is prevelant, replenished b
      • I'll repost the rebuttal: the energy removed from the slipstream is estimated at 1/10th of 1 percent if the entire planet were to be powered by these devices.

        First, how do you know whether 0.1% is significant or insignificant? This isn't your kitchen fan, this is a planetary wide wind system.

        Second, if these devices actually yield cheap abundant energy, that percentage won't stay at 0.1%, it will increase.

        The energy removed from the atmosphere when the planet's coal plants were disabled might far overshado

        • The planet isn't some big lump of rock

          sure it is. You're thinking of the biosphere, which is the Earth we actually care about.

          I'm not. I think the solution to our energy problems is to reduce energy usage, not to keep looking for that magic bullet solution of abundant, free energy.

          Looking for a "magic bullet" solution sparked the industrial revolution, bub. The "free" energy of the river replaced the hard work of grinding by hand. The "free" chemical energy of whale oil replaced the difficult process of making candles. And, most recently,

          • sure it is. You're thinking of the biosphere, which is the Earth we actually care about.

            You're apparently having trouble with some of the different meanings of "planet".

            Looking for a "magic bullet" solution sparked the industrial revolution, bub.

            The 19th and early 20th century was the time of hucksters and snake oil salesmen, people selling products responsible for a lot of death and suffering. These days, our drugs are carefully screened and tested.

            And just like we have learned a lot about how to introduc
        • Okay, hotshot. Prove that it IS a problem. Until then, I'm perfectly willing to have a clean renewable source of energy instead of the smog-producing nightmares I'm currently using.

          Your suggestion that we reduce energy usage is nice, but where do you draw the line? Do we go back to the hunter-gatherer days of yore when we consumed little energy but died around age 20? How far should we go to compromise our comfortable lifestyle so that you can feel good about using one less kilowatt hour per person?

    • Re:maybe not... (Score:4, Insightful)

      by FooAtWFU ( 699187 ) on Saturday April 14, 2007 @11:37AM (#18732357) Homepage
      Compare and contrast the energy removed from the air by a 40MW wind farm and the thermal energy released into the environment by a 40MW coal plant (never mind the emissions just this instant, either). Which do you think has a greater impact on atmospheric conditions?

      • Re: (Score:3, Insightful)

        by nanosquid ( 1074949 )
        Which do you think has a greater impact on atmospheric conditions?

        I have no idea. In fact nobody does. And that's my point.
        • Then we should be all for these kind of alternative energy generation.
          We know that coal-fired plants have a large negetive impact on the environment so trying new forms of energy is the only sensible way forward.
          To be cautious about exploring new sources of energy because of unknown environmental impact seems overly superstitious to me.

          Ben
          • To be cautious about exploring new sources of energy because of unknown environmental impact seems overly superstitious to me.

            I'm not "cautious about exploring" them, I'm simply pointing out that there is a good chance that they will have a harmful impact on the environment.

            We know that coal-fired plants have a large negetive impact on the environment so trying new forms of energy is the only sensible way forward.

            Actually, the sensible way forward is to greatly reduce our energy usage. We could easily redu
    • I don't have the expertise to even guess how this could affect weather. However, I do know that the rotor style blades of this proposed generator are very much like those of an helicopter. While air currents turn the blades, the blades also generate air currents and turbulence by turning. I wonder what the net loss or gain would be. Perhaps an aeronautical engineer specializing in helicopters knows.
    • As I mentioned in the dupe... Global Warming is really a problem of too much energy in the atomsphereic system, harnessing some of it might be a good way to mitigate some of the ill effects.

    • that energy is doing something right now: mixing the atmosphere, generating heat, etc., and chances are that whatever it is doing is probably important for keeping the atmosphere the way we know and like it.
      Somebody in the global-warming-doomsday-tomorrow camp probably wants you to die right now.

    • Re: (Score:3, Informative)

      by InvalidError ( 771317 )
      I would be far more concerned with the sky falling.

      Cables can snap, structures and components can fail, flying wind turbines get in the way of air traffic, etc. To be reasonably safe, flying power farms would need to be at least 50km from inhabited areas (maybe more, depending on how slowly they and their components crash given any particular failure mode) and 100km away from all commercial air corridors to avoid interference with emergency landings since planes can certainly plow through a wind farm faster

  • Cessna Swatters (Score:3, Funny)

    by Anonymous Coward on Saturday April 14, 2007 @10:58AM (#18732017)
    Won't someone please think of the Cessnas??!!
    • Well, fun aside, a barely visible line of aluminium would be pretty hard to see for pilots. Of course, you wouldn't put it in air lanes, but a stray plane would be toast (literally, with all the power going through the lines) if it would fly against it. I presume it also handles thunder(storms) but lets be naive and think they've thought this all through.

      • Re: (Score:2)

        by Dan Ost ( 415913 )
        Thunderstorms shouldn't be a problem. These things will be placed high enough to be above such weather systems.
    • I fly a small single engine Cessna pretty regularly.

      I would run out of gas and die of hypoxia before I reached anywhere near 15000 feet. But hitting that cable would be more exciting than a two liter bottle of Jolt Cola.
      • There are a lot of general aviation pilots who fly planes which can exceed those altitudes, especially experimental aircraft (Long-EZ and derivatives, Lancair, and more recently, homebuilt jets like Viper and Maverick, although I think Maverick may be certified-only now). Not only that, between the "flying" height of 15,000' and the ground, there is a cable that will concern pilots at ANY flight level.

  • I welcome (Score:1, Offtopic)

    by WetCat ( 558132 )
    I, for one, welcome our high-flying wind-powered overlords!
    Seriously, it reminds me of a flying isle Laputa from the famous Jonathan Swift novel...
  • a while ago somebody proposed floating off-shore wind turbines, now flying wind turbines.
    who knows, maybe in a couple of years there will be underground wind turbines, that will harness the strong winds in caves

    what's wrong with keeping them on the ground?

    • Re: (Score:2)

      by 246o1 ( 914193 )
      "a while ago somebody proposed floating off-shore wind turbines, now flying wind turbines.
      who knows, maybe in a couple of years there will be underground wind turbines, that will harness the strong winds in caves

      what's wrong with keeping them on the ground?"

      If there's economic incentive to build the other kinds of wind farms, then what's wrong is the efficiency level.

  • Global warming (Score:3, Funny)

    by javilon ( 99157 ) on Saturday April 14, 2007 @11:21AM (#18732219) Homepage
    If we extract lots of energy from the wind that would make the atmosphere cooler I guess. So this would work against global warming in two fronts.

    • Interesting? (Score:5, Insightful)

      by cliveholloway ( 132299 ) on Saturday April 14, 2007 @11:41AM (#18732373) Homepage Journal
      That's like saying we can raise sea levels by pissing in the sea. Just do the math ffs...
      • Well yes and no. I mean yes, it won't introduce any noticeable temperature difference in the atmosphere for sure, but it could destabilize whatever climate system that depends on the jet stream somehow. I'm certainly not a specialist, but I recall having read about 15 years ago an article about a project consisting of giant underwater turbines anchored in the gulf stream in the middle of the gulf of Mexico, to extract energy from moving masses of water. I remember the article said that it wouldn't slow down

      • Re: (Score:2)

        by javilon ( 99157 )
        Well, you would actually raise the sea levels although not very much. But this would work against us on the global warming front as your piss would be warm.
    • Since this story is a dupe, [slashdot.org] I could refer you to one of many rebuttals for your comment, but I'll just summarize them.

      1. No
      2. There is lots of energy in the wind, we cannot extract much of it
      3. High altitute winds are powered by temperature differentials, which we'll be leaving alone

      This might help mitigate global climate change, not because we're extracting energy, but because we could move away from burning stuff to make energy.

      P.S. Nothing humans will do can compare to the amount of heat reflected/radiat
    • The article says that with 1% of the higher winds harnassed, we could power the human race. Presumely a few of these devices will only use .001% of the power available to them. If this works it would stop us from converting oil to CO2, but the direct cooling effect is not something I am going to count on to stop global warming. It's nice that it would be energy-neutral in the *very* long run, I give you that. It won't heat up the earth.
    • Actually, it would warm the earth when you slow that air current..but still..I get your joke. ;)
  • We'll need an unbreakable diamond tether to make it profitable...
  • Kirov reporting ...

  • It is simple (Score:3, Funny)

    by zoomshorts ( 137587 ) on Saturday April 14, 2007 @12:53PM (#18733053)
    No matter what you make wind powered stuff from, it will take MORE energy and resources to ever pay back the initial investment in time, materials and ecological drain !!! Same with solar et al. Do the analysis. Figure it out.

    You cannot even afford to produce pencils.

    • Re: (Score:1)

      by thorkyl ( 739500 )
      Your right, lets burn more dead dino's

      I did the analysis, thats why I am going solar and wind.
      Stuff is being delivered in the fall after hurricane season...
  • Shame about that 737 though.

    See http://en.wikipedia.org/wiki/Barrage_balloon [wikipedia.org]

  • Even a hundred or do feet up there's almost a constant stream of air blowing around. I say this as one who is a radio amateur (ham) and have been up in high places several times. In each time, regardless of the season, there's always a breeze once you get up about 70 feet.

    But I do like the idea of getting 40mW of power out of flying platforms. Put it this way, about ten of these would supply the city I live in.
  • Let's be realistic. Anything in the atmosphere that's tethered to the ground is in for trouble. Be it a 40MW generator, a space elevator, an advertisement, or whatever, sooner or later it's going to get violently disconnected. Odds anyone?


  • Just wondering aloud here...

    Instead of putting the generators in the air, perhaps they could just put a big kite up there with carbon nano-fibers connecting it to a base station on the surface of the ocean. The cables could connect to a pulley system at the bottom of the ocean. As the jetstream yanks the kite about, the cable turns wheels connected to a generator on the ocean surface. They also submerge huge bouys that go to the bottom of the ocean.

    The idea of the bouys is to capture the energy that wo

    • Re: (Score:2)

      by rohar ( 253766 ) *
      You might have just invented the sail boat. :)
      • Sorry to be confusing. The ocean-based generator is stationary. It doesn't move. Instead, the kite moves around taking up and letting out cable, which spin gears connected to a generator on the surface of the ocean. The bouys act as a counter weight to drag excess cabling back in when the jetstream's fury is reduced.

        The reason you go with a bouy system is that it is extremely scalable. You could just have a huge weight going down a hole, but then when the jetstream's force pulls the weight all the way u

    • It's suggested as an alternative.

      Two kites, with control surfaces to allow them to make less drag when on the retrieve leg. Much better plan then pulling a (very strong) buoy deep under water.

  • This has potential... (Score:3, Funny)

    by rohar ( 253766 ) * <bob.rohatensky@sasktel.net> on Saturday April 14, 2007 @02:42PM (#18734013) Homepage Journal
    ...to become an intermittent source of renewable power. They are probably doing the project harm with the "Potentially Our Cheapest Energy Source. We Don't Need Oil!" and "Key to Energy Independence and Arresting Global Warming" claims their website, but they do have something that could at least become a supplementary energy source. It's hard to tell if the PITA factor of managing these over a wind turbine on a fixed tower is worth the much higher output.

    This could make a great historical demonstration of Ben Franklin's lightning/kite experiment when lightning [wikipedia.org] "improves" the efficiency of the system by finding the shortest path to ground by dropping 500MW for 1 sec down a 40MW cable. (Don't touch the key hanging on the end). The instant heating [wikipedia.org] to 28,000C might also cause a few issues. Lightning can be formed in man circumstances, so watching out for cumulo nimbus clouds and pulling down the system isn't a sure bet.

    The only thing I could find on lightning in their information was in the pdf [stanford.edu]:

    "Generator and tether performance depend on a good lightning storm detection system. Surge protection schemes and hardening of the control systems are also under examination."

    I am a proponent of Open [shpegs.org], Renewable [shpegs.org] and Baseload Reliable [shpegs.org] systems.

  • It's all fun until mad scientists run amok... (Score:5, Funny)

    by NotQuiteReal ( 608241 ) on Saturday April 14, 2007 @02:46PM (#18734053) Journal
    From the article: Dr Ockels's team is building a 100kW prototype...

    Is anyone else concerned that there will be a "Doc Ock" working with a high energy device?

    Of course, the anchor tether will have to be stronger than spider's silk, so there should be someone on hand to keep Doc Ock in check! [imdb.com]

  • They should just shovel all the B.S. that comes out of Congress into giant bioreactors, generating electricity AND excellent fertilizer at the same time.

    In the winter, they should hold open-door meetings, so that all the hot air they blow can flow out through the doors into the city, and keep the Eastern Seaboard nice and cozy during those nasty winters.

    -----

    Dilbert: "If I do that, the Special Interests win. The integrity of out democratic process will be violated. Our Founding Fathers would spin in their

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