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Kite Power: The Latest In Green Technology ( 103

New submitter Dan Drollette writes: The solution to producing energy without contributing to global warming may be to go fly a kite. Literally. Researchers in Switzerland and Italy — high-altitude places where the winds are strong, steady and predictable — have been working on ways to generate electricity from kites that fly hundreds or thousands of meters high. The scientists already have a prototype cranking out 27 megawatts; they expect to have a 100-megawatt plant big enough to power 86,000 households. And they say that they can produce electricity for less that 4 cents per kilowatt-hour, which is better than fossil fuel. Plus, the kites look really cool (as does the "Darrieus rotor vertical axis wind turbine" at the base of the St Bernard Pass, on the Swiss side, which I've seen in operation in person).
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Kite Power: The Latest In Green Technology

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  • Prior Art (Score:4, Informative)

    by Anonymous Coward on Friday January 15, 2016 @01:57AM (#51305377)

    I think they forgot to google for the technology first:

    • The second (and perhaps less researched) approach is to minimize power utilization . It finally has to be a balance between clean power generation and efficient utilization .
      • Re:One handed clap (Score:4, Interesting)

        by dbIII ( 701233 ) on Friday January 15, 2016 @03:12AM (#51305503)
        Less researched?
        It's the road most followed.
        Even traffic lights have LEDs in them now. People who did not care about building insulation at all a few years ago have it. Roofs are being painted white. We could always do more but it is definitely not being ignored.
        • Re:One handed clap (Score:4, Insightful)

          by invictusvoyd ( 3546069 ) on Friday January 15, 2016 @04:11AM (#51305597)
          The largest power consumers of the future are going to be developing countries like China and India . Not much is being done there.
          • thats not quite true. if you have a look on this site, you'll find out more about how much china and india are really doing
          • Re:One handed clap (Score:5, Informative)

            by Whibla ( 210729 ) on Friday January 15, 2016 @08:16AM (#51306093)

            Not much? Seriously?

            In the 2006-2010 five year plan the real improvements in China's energy usage came from two programs.

            Firstly, in the Thousand Enterprises Program the government forced China's top 1000 companies to completely rethink their energy use. They were told to monitor energy efficiency, and redesign, upgrade, and / or replace industrial equipment and software with the aim of becoming more energy efficient, reducing the amount of power they used without denting their productivity. The other program was even more drastic. Thousands of small, inefficient, factory units and assembly lines across the country were simply closed down.

            The above programs were so successful (a roughly 19% cut in their energy intensity) that they were extended and expanded for the current five year plan: smaller, inefficient units are continuing to close down, and the Thousand Enterprises Program has become the Ten Thousand Enterprise Program. Current indications suggest that China has met its target of a further 16% cut in their energy intensity.

            In addition, China has more installed wind power than any other country in the world, and has the second largest installed solar power capacity. I've also read that they (the Chinese government) are actively looking at new nuclear power plant designs as well as thorium salt reactor designs, which is a direct contrast to pretty much every single western government.

            If all this qualifies as "not much" I'm not sure what it would take to impress...

            • Re:One handed clap (Score:5, Interesting)

              by thegarbz ( 1787294 ) on Friday January 15, 2016 @09:54AM (#51306613)

              Even if China isn't exploring new fancy nuclear designs, they currently have 26GW of generation capacity, they are bringing a further 40GW online in the immediate future (plants already under construction many of which are nearly finished), and a further 50GW of generation capacity is already planned beyond that. That's a bigger push for CO2 free energy than a lot of other countries are currently making.

          • Re:One handed clap (Score:4, Insightful)

            by dave420 ( 699308 ) on Friday January 15, 2016 @12:19PM (#51307687)

            I guess you just like having someone to point to and say "well, they're worse than me, so I can continue being wasteful", as you clearly haven't spent any time looking for supporting evidence.

        • by umghhh ( 965931 )
          condoms for the poor of the world would do too.
          • Re:One handed clap (Score:5, Interesting)

            by Sique ( 173459 ) on Friday January 15, 2016 @05:13AM (#51305691) Homepage
            That's a common misconception. The birth rates are high only in regions with a long lasting, ongoing civil war, like Afghanistan, Somalia or Zaire. And that are places where you can't distribute condoms without being shot at sight.

            Most other countries have continously falling birth rates, even the so called poor ones. The average birth rate in the African countries for instance is close to 2.5 children per woman, not much higher than for instance the U.S..

            • by Lennie ( 16154 )

              One word:

              • Re:One handed clap (Score:5, Informative)

                by Sique ( 173459 ) on Friday January 15, 2016 @06:52AM (#51305867) Homepage
                Appearently (and supported by much demographic data), birth rates are not related to the availability of common contraceptiva. Case in point: The pill, introduced in 1963. The birth rate in the U.S. was already declining at the end of the 1950ies, before the pill became available. The birth rate in European countries was declining only five years after the pill became available. Thus while the pill was available nearly at the same time in the U.S. and in European countries, the beginning of declining birth rates was 10 years apart. The introduction of the pill and declining birth rates seems to be a classical case of correlation, but not causation.

                Thus back to airbombing people with the condom: It won't affect the birth rate. Birth rates decline in all countries with rising female education levels and better health care, wether you carpet bomb them with condoms or not.

      • Build far enough underground and there would be little need for air conditioning. There would be no weather problems. Driving in tunnels would be far easier as there would be no pedestrians or wildlife. Even if the costs are enormous and it take centuries to justify the expense, the savings after that would be far more than the expenses. We just need to learn from Bertha in Seattle.

      • There is enough energy in, on, and above the planet to provide for current needs, and for projected needs into the arbitrary future. Wind, solar, geothermal, and nuclear sources of energy can be -- and are! -- deployed more and more as energy scientists and energy engineers find ways to get to them and exploit them. There is no scarcity of energy on this planet, there is only a lack of access. So asserting that we need to use all this energy efficiently is misguided at best, and really doesn't help with

    • Re:Prior Art (Score:5, Interesting)

      by tempmpi ( 233132 ) on Friday January 15, 2016 @05:22AM (#51305707)

      Makani uses a completely different approach: They use a wind turbine to generate electric energy and just use a kite to get the turbine to 250m height, while the kites from switzerland are basically passive kites and the aerodynamic lift is used for generation of power. Makani could generate energy contiguously while this SwissKitePower approach would alternate between ascend and retraction phases and only produce power during ascend.

      • This sounds like approach SkySails uses. See from 1:50 in this video. []

        They are the ones who make kites for large ships. (Shown at 4:20 in the same video.)

        • Soft kites have to be replaced quite often since the fabric wears out. SkySails can get away with it because the ships save more fuel than it took to manufacture the kite. It is cheaper to make them big, but that is offset by them being about 1/10 as aerodynamically efficient as a rigid wing.
      • I don't know whether there 100kW estimate was during the ascent stage or descent. I'm surprised it's generating during ascent. Would be easier to harness energy on the way down. But in any event, you could have two kites 180 degrees out of phase so to speak to ensure pretty continuous power.l
  • What happens if the wind stops? Do I get a free repair to my roof?

    • by Waffle Iron ( 339739 ) on Friday January 15, 2016 @02:03AM (#51305383)

      What happens if the wind stops?

      The utility plant operators have to compensate by running backwards and pulling harder on the string.

    • by AHuxley ( 892839 )
      Depends on the size and scale of the project.
      "US army blimp wreaks havoc after breaking free from military facility" (2015/oct/28) []
      "... dragging its 10,000 foot long cable behind it and knocking out power to thousands."
      • by Iconoc ( 2646179 )
        I was away from the computer when I heard about this. It is such a laughable event and yet I saw no American media coverage after minimal searching a week later. $2.8 Billion doesn't buy much anymore. I guess this seems like a good idea when you're spending someone else's money.
      • Re:fast winds (Score:4, Interesting)

        by Rei ( 128717 ) on Friday January 15, 2016 @08:35AM (#51306175) Homepage

        That's part of the reason that blimps are increasingly going out of favor, in favor of hybrid airships. Hybrids are based on the concept of being aircraft (generally lifting-body aircraft) that get huge lifting areas via inflation (so that they don't need any real structural strength, and thus keep the mass very low), and use helium as the inflation gas, which partially (but not completely) lifts the craft. So you have the combination of huge lifting area and much of your weight compensated for, so it takes little energy to stay aloft (which can, for example, come from solar), and unpowered landings are perfectly safe. But because (for the same payload capacity) you don't need as big of a gas bag as with a blimp, they're not as vulnerable to crosswinds and thus not as likely to break free, as well as being much easier to land without being blown into power lines or whatnot.

    • by amiga3D ( 567632 )

      If you put it all the way up into the Jet Stream it would be pretty steady.

    • by AmiMoJo ( 196126 )

      At the altitude they are using there will always be enough wind to keep the thing in the sky. The amount of energy generated might vary, but it won't fall down.

  • by sectokia ( 3999401 ) on Friday January 15, 2016 @02:07AM (#51305393)
    27Mw is no small prototype, but there seems to be nothing about it anywhere.
    • by gl4ss ( 559668 )

      they say turin.

      it's different company.

      27 is peak, so, it might not mean anything significant or it might. if it meant anything significant then that 'research' should already be self financing.. I would think.

    • 27Mw is no small prototype, but there seems to be nothing about it anywhere.

      That's how it is with prototypes.

      This is why the word begins with the Latin root protos, meaning first or primitive.

  • by Dasher42 ( 514179 ) on Friday January 15, 2016 @02:31AM (#51305441)

    This has been around a while; kites, windbelts, and laddermills were my area to cover for presentations when taking classes on sustainable energy in 2010, and they were a lot of fun. Anything that gives you an excuse to play footage of the Tacoma Narrows Bridge collapsing and demonstrating the awesome power of wind is pretty cool.

    Kites hold a lot of promise; they're far safer for wildlife than any turbine, even the large slow ones that don't deserve their bad rap, and they produce up to a third of a turbine's power given similar operating area, for a tiny sliver of the material cost. Solar's cool and all, but wind power has become surprisingly diverse in its options tailored for different environments, and is becoming more so.

    • Solar's cool and all, ...

      Speaking of which - it would potentially be worth putting solar panels on the sunny side of a kite.

    • Indeed it has been around for a while. I'm not sure who the inventor is but I know that Dutch Astronaut Wubbo Ockels [] conceived the idea for himself in 1995 and start filing patents [], the first one being 1997 []. Here's a video [] with a prototype which was used to (partially) power the music at a Dutch concert some years ago. Strange that there is no mention of him in the cited article.
    • by hippo ( 107522 )

      > demonstrating the awesome stupidity of the Tacoma Narrows Bridge designers.


      (Actually that may be a bit harsh, ignorance may be a better word)

    • Yeah, the bad rap that big wind turbines get is undeserved.

      Skyscrapers and power lines kill far more birds than wind turbines.

      And, y'know, I never heard anyone sling that mud at the idea of a Space Elevator. . . I wonder why.

  • is dirt-cheap. Here in Austria, I pay around 18 cents per kWh for power that comes for 80% from wind and water plants. I guess this part of the country would have a potential comparable to that of Switzerland, due to comparable geography: a rather flat basin (of the Danube) with the Alps close.

  • Up until a year ago I was doing research in this field. Google/Makani is by far the closest to commercialization at utility scale. They are already on their 8th prototype, a 600 kW version. Nothing public is operating anything airborne in the Megawatts yet.
  • by GumphMaster ( 772693 ) on Friday January 15, 2016 @03:31AM (#51305541)
    I can see a lot of fun with aeronautical obstacle databases if this takes off in a big way. Essentially a power plant will need an airspace allocation up to 10000 feet AGL and a nautical mile or two across. Put a lot of these around a city and there are many aeronautical procedure designers that will certainly be cursing as they try to thread an aircraft safely between them.
    • by paulatz ( 744216 )
      Flight restrictions, both permanent and temporary, are already quite common, there are a few websites that show maps of them (one relatively user friendly is [] ), checking where they are and avoiding them is part of the normal flight routine.
      • Flight restrictions, both permanent and temporary, are already quite common, there are a few websites that show maps of them (one relatively user friendly is [] ), checking where they are and avoiding them is part of the normal flight routine.

        Ok, but how often are they accidentally entered into anyway and how many consist of 10,000' high series of barrage balloons equivalents probably capable to bringing a plane down?

  • by Anonymous Coward

    Yes, sure, for us it does. I am pretty convinced though that the folks living in the neighborhood of such a power plant will have a different opinion on that.

    The 27MW takes 9 kites flying at 10km altitude. That means a measly 100MW plant will consist of 33 kites. A 1GW plant requires ~330 kites.
    Nobody wants this in their neighborhood, just as everybody likes wind-power but nobody wants the windmill in his backyard.

    Also, the large scale introduction of kites, flying at 10km height, is going to be an issue fo

    • by Rei ( 128717 )

      Who wants any kind of 100MW plant in their backyard? 100MW is an awful lot of power. Doesn't matter how you generate it, it's going to have to involve some combination of extreme areas, extreme pressures, and extreme temperatures - otherwise the physics doesn't work. If you want it small, it's going to have to be high pressure and/or hot. If you want it low pressure and cool, it's got to be huge. This ignores all other potential issues with each given type of power plant...

  • by Rob Lister ( 4174831 ) on Friday January 15, 2016 @08:47AM (#51306225)
    Having read the article, I'm entirely convinced this is not scalable; we're not going to power cities with this. I'm not convinced it is not useful in some places at some times; small remote towns that don't have anything else would find it cheap and useful. It is clever. Assuming the wind blows [way up yonder] with great consistency, this has a lot of promise. My gut tells me you'll need to fly at least three to make it close to distributable; Like juggling. Obviously the more that are flying, the more consistent the result will be (as long as the wind keeps blowing). My gut is often wrong. Can any of you smart guys model this?
    • But consider, the power generation for a city is already massive. I'm trying to find a useful example and it's hard, but look at 2013 Rhode Island electricity use in 2013, [] - 7.8 million MWh purchased (if I'm reading the page correctly). That's for about a million state residents.

      So to pick a nuclear power plant at relatively random, the Braidwood nuclear plant in Illinois generates about 20 million MWh per year at a construction cost of $5.2 billion. To generate the
  • It looks like a parachute. How exactly is that "really cool looking"?
  • So wind blows in one direction for the most part and they want to use kites to generate power? Kites blow in one direction too. It takes energy to pull them back. That's why you don't make an unlimited magical energy generator that uses the power of gravity. Gravity pulls in one direction so eventually you have to lift the item against gravity. The same basic principal happens with wind and kites.
    So use that as a starting point and then look at the diagram of the ridiculously over-complicated kite sys

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