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Harnessing High Altitude Wind Power

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."

11 of 132 comments (clear)

  1. Dupe. by frakir · · Score: 5, Interesting

    Not only is this a dupe (http://science.slashdot.org/article.pl?sid=07/04/ 04/2142232) but there are much better ideas.
    Check http://www.magenn.com/ for example. And much less dangerous.

    1. Re:Dupe. by florescent_beige · · Score: 5, Interesting

      I'm happen to be an expert in aircraft structures and based on what I said 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.

      --
      Equine Mammals Are Considerably Smaller
  2. maybe not... by nanosquid · · Score: 4, Insightful

    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.

    1. Re:maybe not... by maxume · · Score: 3, Informative

      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 terawatt= 1*10^12 watts; 1.45*10^17 watts=145000 terawatts; 12 is 0.008% of 145000.)

      --
      Nerd rage is the funniest rage.
    2. Re:maybe not... by FooAtWFU · · Score: 3, Insightful

      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?

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      The World Wide Web is dying. Soon, we shall have only the Internet.
  3. Cessna Swatters by Anonymous Coward · · Score: 3, Funny

    Won't someone please think of the Cessnas??!!

  4. Re:rather old news.. by Deadstick · · Score: 3, Funny

    It still is...and it's at the forefront of dupes too.

    rj

  5. Interesting? by cliveholloway · · Score: 4, Insightful

    That's like saying we can raise sea levels by pissing in the sea. Just do the math ffs...

    --
    -- Trinity in high heels carrying a whip: The donimatrix - there is no spoonerism
  6. Re:now i've seen it all by zippthorne · · Score: 5, Insightful

    The problem is that the people who find them unattractive or noisy (noisy?? I live near one, i've never heard it. The highway on the other hand...) are the same people who want to get rid of coal (because of the soot), oil (because of the carbon), Hydroelectric (because of the fishes), nuclear (because of the bomb), solar-dynamic (because of the 7-years bad luck), and probably have some kind of cockamamie objection to geothermal, too.

    These are the same people that move in near airports (because of the low-prices) and then complain about the noise and occasional fuel dump. THAT'S WHY THE PRICES WERE LOW. The airport's been there for 80 years, so you had to know what you were getting yourself into.

    I'm a GW skeptic, but I'm all about buying efficient devices and trying alternative energy, especially if a non-governmental organization has found a way actually make something profitable. I get disheartened and disillusioned with "environmentalism" when the very people clamoring for alternative energy are the ones shooting down the projects.

    We should have some kind of survey, and have people check off the kinds of power they don't want near them, and if they check off too many items, they're not allowed to talk.

    --
    Can you be Even More Awesome?!
  7. Moving target by mangu · · Score: 3, Insightful
    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.

  8. It's all fun until mad scientists run amok... by NotQuiteReal · · Score: 4, Funny
    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!

    --
    This issue is a bit more complicated than you think.