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Power Technology

Generating Power From Ocean Buoys and Kites 131

cheezitmike writes "Researchers at Oregon State University are testing a new type of wave-energy converter to generate electricity from ocean waves: 'Even when the ocean seems calm, swells are moving water up and down sufficiently to generate electricity. ... For decades the challenge has been to build a device that can withstand monster waves and gale-force winds, not to mention corrosive saltwater, seaweed, floating debris and curious marine mammals. ... In the most recent prototypes, a thick coil of copper wire is inside the first component, which is anchored to the seafloor. The second component is a magnet attached to a float that moves up and down freely with the waves. As the magnet is heaved by the waves, its magnetic field moves along the stationary coil of copper wire. This motion induces a current in the wire — electricity.'" Meanwhile, researchers at Stanford are working to design "turbine kites" that operate at 30,000 feet, where air currents flow much faster than they do close to the ground. Ken Caldeira, a Stanford associate professor, said, "If you tapped into 1% of the power in high-altitude winds, that would be enough to continuously power all civilization."
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Generating Power From Ocean Buoys and Kites

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  • Someone got the wiring wrong. Poor fishies.
  • Surely that would require no significant amount of resources to be tapped. Maybe just an area the size of Australia? Not sure about that though. Please correct me if I'm wrong.
    • If I only had mod points... This raises a question as to whether or not an idea of this magnitude comes to fruition through scientific means (not sexy) or political means (sexy to Al Gore).
      Yes, it may power a civilization... but to what end? If it means stronger tornadoes in the midwest, it could be both tragic and expensive. The natural resources used to produce such a device would be somewhat trivial compared to usual consumption, but what impact would this have on us common folk?
      • by aurispector ( 530273 ) on Saturday July 04, 2009 @10:20AM (#28579929)

        Oh, for God's sake this neurotic fingernail chewing has to stop. Any energy used to create electricity MUST, by the laws of physics, come from somewhere else. Sorry kiddies, but there is no magic wand to make energy appear without some consequences. Grow up.

        By choosing to shoot down any and all alt-energy methods, you thereby choose to continue burning fossil fuels as the major method of electricity generation, which is also the majority source of carbon and old school pollution.

        It's time to put on your big-boy pants, recognize we have a problem that needs solutions NOW and be willing to deal with the consequences. The second worst thing we could do, next to "nothing", is pick a single new method to pursue. We need to try them all to see what works, what the problems are, etc.. The answer will probably be a mix of new technologies.

        We've become a nation, no a WORLD of spoiled whiners. Man up, take some fucking responsibility and DO something. Spoiled whining children should be spanked.

        • We're not whining. We're just discussing. We know what must happen, but, also realize that it's going to tear the world apart & we don't like it.
          • No it isn't. You must suffer from some sort of adolescent apocalypse obsession. Wipe off the goth makeup and stop being so emo, it's annoying.

    • Re: (Score:3, Informative)

      by houstonbofh ( 602064 )
      Just don't think about transmission losses... Those pesky realities mess up perfectly good theories.
      • Some lines are more efficient than others, but the technology is available to take energy all the way across the country, with the losses of maybe fifteen percent. Look up "High Voltage Direct Current []."

        When you portray yourself as a pesky realist who actually understands how things work, it helps if you actually understand how things work.

    • by TheRaven64 ( 641858 ) on Saturday July 04, 2009 @06:14AM (#28578979) Journal
      Exactly my thought. 1% is a tiny number, until you multiply it by the surface area of the Earth. Let's talk some real numbers instead. Current world power consumption is around 500 Exajoules per year, or about 15 TW on average. About 89 PW of solar energy hits the Earth's surface. This means that you'd need 0.017% of the Earth's surface to be converted to solar power to generate enough power for the entire world[1]. Now let's turn these into real numbers, rather than percentages. The surface area of the world is 510,072,000km^2. For solar, you'd need 85,967.191km^2, or a square around 300km on each side. For wind energy, you'd need 5,100,720km^2, or a square around 2250km on each side. Which of these sounds more feasible?

      The figures for solar are using the average power, but it's worth noting that a number of the places with the highest solar energy are not particularly suited to human habitation. The Sahara desert is 9,000,000km^2. Enough solar energy hits less than 1% of the Sahara to power the entire world.

      That's not to say wind power is a waste of time. The nice thing about this idea is that it works at night. Without some very efficient storage system or room-temperature superconductors, it's not feasible to power the whole world with solar energy. It's much easier to take things like this seriously, however, without the needless hyperbole.

      [1] Note I'm assuming 100% efficiency here. The original article stated 1% of the energy in the wind, not 1% of the extractable energy, meaning that he was also assuming 100% efficiency. Back in the real world, scale all of the areas up by another order of magnitude or so.

      • Realistically though - you would never ever want all of the world's electricity production in one location or from one method.

        Obvious political reasons - see Middle East OPEC Cartel for more information on this.

        Power distribution nightmares - although super conducting main lines like they're using in New York are very promising.

        Night / Day transitions - At night, the desert won't be generating anything.

        SimCity Microwave Power is the only answer... and a great weapon to use if someone pisses you off.

  • Nature itself uses tech. similar to solar panels (green leaves) to get the energy it needs, not the wind or waves.

    My bet is on more efficient solar panels, a solid state power collectors.
    • by smoker2 ( 750216 )
      Call me back when nature uses photosynthesis to create electricity.
      • "Call me back when nature uses photosynthesis to create electricity."
        *Ring ring*

      • Light-dependent reactions [] in photosynthetic organisms involve light causing a transfer of electrons from chlorophyll molecules to the electron transport chain. Since electricity is simply energy in the form of charged particles, the transfer of electrons involved in photosynthesis is one way that nature uses photosynthesis to create electricity.
  • The challenge with this plan is how are they going to transmit the energy from 30,000 feet? How much does 40,000 feet of cable weigh? That's about 7 miles. Perhaps they could use lightweight tether and beam the energy using microwave like the space energy proposal but that adds complexity. BTW, The design referred to in the article uses a series of helicopter-like blades to sustain lift and generate electricity.


    • by unl0rd ( 930446 )
      wireless power of course!
    • by Anonymous Coward

      The simplest idea I've seen uses a kite on the end of a tether. The tether is paid out, generating energy, and then pulled back in, requiring energy. By changing the kite's angle of attack during the recovery phase, a net energy output can be obtained.

      The energy output is supposed to be around 20kW per square metre... is there any reason why this wouldn't scale to 20GW for square-kilometre kites?

    • How much does 40,000 feet of cable weigh?

      Go to the top of the class !

      This was briefly discussed in Number Watch [] a few years ago.

      • How much does 40,000 feet of cable weigh?

        Go to the top of the class !

        This was briefly discussed in Number Watch [] a few years ago.

        I looked at that site and I am unimpressed. The guy doesn't give any numbers (despite calling his site "numberwatch"), his only argument is that _he_ can't imagine it working because he can't build it with his engineering skills - without even knowing details of the plan. That is exactly the sort of useless whinging that this thread is about.

        Looking at the rest of the site, it seems to be the work of an unhinged libertarian-turned-global-warming-denier who thinks he is much smarter than everybody else, obvi

  • Stop the Irony (Score:4, Insightful)

    by daath93 ( 1356187 ) on Saturday July 04, 2009 @03:07AM (#28578369)
    Here in Oregon the greenies have been fighting against the energy buoys for a while. They are concerned that electromagnetic cables on the ocean floor could affect sea life, and that buoys could interfere with whale and fish migration. We've also been tearing down hydroelectric dams because it disturbs the salmon. We got Washington DC jacking up the price of non-enviro friendly electricity on one end and the greenies on the other end kicking the green energy in the balls.
    • Re: (Score:1, Insightful)

      by Anonymous Coward

      Taken to the extreme, the green ideology and its precautionary principle demands suicide.

      These people need to go outside and kill something. Seriously. Animals and plants die. It's a given.

      But as long as we don't burn fossil fuels on a massive scale, don't emit any poisons in bigger quantities or higher concentrations than we found them, as long as we make sure that we permanently set aside 10%-30% of all land, and lakes, and sea, and ocean, as long as we do that nature will be fine. This is coming from an

    • Re:Stop the Irony (Score:5, Insightful)

      by TapeCutter ( 624760 ) * on Saturday July 04, 2009 @05:52AM (#28578917) Journal
      Right, lets stop the irony and blame the greenies, lets ignore the fact the dams are 80yrs old, poorly designed and commercial fishermen [] want them altered/removed to allow salmon to spawn. Seems to me it's simply a failure to invest in modern infrastructure (fish ladders), failure to reinvest seems to be a bad habit power companies have picked up these days.
      • by hitmark ( 640295 )

        More that boiling the message down to a one sentence eyeball grabbing headline ends up removing all the sane details of said message...

        The paradox happens when the headlines are put up against each other, with no details included...

    • Re: (Score:2, Insightful)

      by drinkypoo ( 153816 )

      Dams are some of the most ecologically disruptive creations of mankind. They are not, repeat not "green" power.

      You could put paddlewheels all up and down every river not being used for transport (and some of those too) and generate hydro power without having to build megalithic dams, but humans seem to be addicted to centralization. There are benefits to be had from it for sure, but [large scale] dams are still bad.

      • by khallow ( 566160 )

        Dams are some of the most ecologically disruptive creations of mankind. They are not, repeat not "green" power.

        Personally, I don't care one way or another. As I see it, "ecologically disruptive" is overrated. Even if humanity turns out to be one of the great ecological disruptions of the past few billion years for Earth, it's for a good cause, namely a space faring technological society. We need a better reason than that to stop building them. That dam does a lot of work for us.

        You could put paddlewheels all up and down every river not being used for transport (and some of those too) and generate hydro power without having to build megalithic dams, but humans seem to be addicted to centralization. There are benefits to be had from it for sure, but [large scale] dams are still bad.

        Building dams is a hell of a lot cheaper and more efficient than building paddlewheels all up and down the river. For example, every time yo

      • Dual purpose (Score:3, Interesting)

        by zogger ( 617870 )

        Most large dams are there also for water storage and flood control, to even the supply out over the year, and we really don't have much in the way of alternatives for that.

        • Most large dams are there also for water storage and flood control, to even the supply out over the year, and we really don't have much in the way of alternatives for that.

          At this point, it's very hard to get away from using dams, but there is no need whatsoever to build any more of them. In most places you can get a meaningful amount of water by collecting roof rainfall in a cistern. Distributed water storage is more durable than unified, anyway; further, there is no particular reason the state should be involved.

    • by MobyDisk ( 75490 )

      Sounds like a very green bunch: A combination of astroturf + money.

      I suspect that the energy lobby is somewhere behind these bizarre anti-sustainability movements. Maybe even convincing poor fools that they are really helping things out.

      • That's why I use only fuel obtained from 100% organic crude oil, flowing the goodness of Mother Earth . I'm confident Exxon fuel comes from free-ranging, happy dinosaurs.

        I wouldn't even think of filling my Prius with fuel that was from living matter trapped and enslaved on some industrial agri-business and force-fed chemical fertilizers.

    • Nuke em.. its the only way to be sure....
  • I'm interested in this topic partly because of its connection to "seasteading" or sea-surface colonization.

    As with other forms of "alternative" energy, though, the problem is cost. Generating energy from renewable sources certainly sounds nifty. But does it make sense for the kind of low-budget settlement that could plausibly exist anytime soon, or even for conventional markets on land? The article summary is about making an energy generator that will work, period, not making something that can compete wi
    • Rather than a big, durable system, why not some kind of cheap low-energy system?

      The problem becomes one that, thus far the economies of scale work such that the huge, big, durable system ultimately has a lower cost per kwh delivered than the small system.

      I've worked the math several times. I just can't make the make work out for a tower, and I live in an area where I'd have a good chance of being able to set one up, in an area that's good for wind. Still, once you have the grid connect...

      I keep coming up with it'd be better to take the money(even considering subsidies), and put it in

  • Google already did this and patend it
  • by Spy Handler ( 822350 ) on Saturday July 04, 2009 @03:34AM (#28578461) Homepage Journal

    "If you tapped into 1% of the power in high-altitude winds, that would be enough to continuously power all civilization."

    And if you tapped into 1% of the power in the heat of the earth's core, that would be enough to power all of civilization on Zeti Reticuli, and if you tapped into 1% of the solar output by building a tiny Dyson sphere that would be enough to power all of Known Space. But let's first ask ourselves, is it practical and cost-effective?

    • by sumdumass ( 711423 ) on Saturday July 04, 2009 @05:08AM (#28578807) Journal

      But let's first ask ourselves, is it practical and cost-effective?

      I'm sure we can cap and trade it into being practical and cost-effective. That's the power of the free market when some people are in charge.

      • So we can *fake* it by artificially raising the prices of better, cheaper, more power-dense energy sources?
        • well, yea,

          that's the point of their "free market". When only the rich can afford energy, the massive amounts or poor will demand something to be done.

          • When only the rich can afford energy, the massive amounts or poor will demand something to be done.

            They'll create an energy-welfare system to ensure that doesn't happen. It's worked for housing and food so far.

    • by Renraku ( 518261 )

      Practical and cost effective?


      Most of earth's problems could be solved by having plentiful, cheap, easy, nearly-free energy. Not enough food? Grow-lights and mineral plants could fix that. Not enough fresh water? Purifiers would be easy to build as-needed along the coast. Not enough diamonds? Plenty of robots to mine them for you.

      • by Mikkeles ( 698461 ) on Saturday July 04, 2009 @07:31AM (#28579205)

        Except the major problem: too many people.

        • by ae1294 ( 1547521 )

          Except the major problem: too many people.

          kill all humans.. I've been saying it for years....

        • That again comes back to energy. In the extreme case, put them on the Moon, Mars, and every inhabitable rock within reach.
      • Presumably to harvest 1% of the wind energy in the upper atmosphere, you'd need to have around 1% of the wind there pass through your turbine. (Probably more, because your turbine isn't going to harvest all the energy in the wind.)

        Is it "nearly free" to have 1% of the stratosphere full of turbine kites? That's a lot of kites...

        • Re: (Score:3, Insightful)

          by WalksOnDirt ( 704461 )

          Probably much less than 1%. The upper altitude wind energy is highly concentrated in the jet streams, so you would get most of your energy from there. The harvesting is greatly complicated by the jet streams wandering around, though.

  • Old news (Score:1, Offtopic)

    by justinlee37 ( 993373 )

    I spent a year at Oregon State University back in 2006-2007. They were talking about the ocean wave generators back then; it seems to be the darling of the engineering department there.

    Don't ever go there by the way. It's in a really small town with an annoying football culture and an annoying number of frat houses, filled with small-time criminals, bored cops, and very few permanent residents.

  • Boondoggle bait (Score:3, Insightful)

    by dontmakemethink ( 1186169 ) on Saturday July 04, 2009 @04:21AM (#28578657)

    Boondoggle: n. work of little or no value done merely to keep or look busy.

    Political favor is unfortunately a far more dominant motivation to develop sustainable energy technology than sustainability itself. I've seen too many boondoggle projects get huge grants because they are the most visible, like big wind farms within sight of a large population, in favor of more suitable locations. If we can't implement a centuries-old technology effectively today at ground level, what good is a new technology in one of the most foreign environments known to mankind? Ignorant energy harvesting is what got us in this mess in the first place!

    I have a strong respect for academic studies, but minds aimed at sustainable living are wasted on these implausible contrivances. There's enough dorks on Star Trek forums trying to prove useless theories. Don't waste our taxes on them.

    • Re: (Score:3, Interesting)

      by Anonymous Coward

      Well, perhaps a nation of 300 million can afford to research more than one thing at a time.

      Both these technologies are sound ideas for research because they both seek to use some of the highest power densities that also are widespread.

      The motion of the waves typically has a higher power density than the wind that created them, which is perhaps not entirely intuitive.

  • Various ideas are tacking center thought of producing green energy here are books about producing []" target="_blank"> alternative energy many guys trying to produce electricity or power for personal useâ¦.
  • I strikes me that in both these solutions, they are using a lot of vulnerable wiring to either transmit the current somewhere it can be used or to actually generate the current. Why not stick to the same principle as hydro-electric ? If you build 2 tall chimneys, one shorter than the other, and join them at the base via a turbine, the pressure difference between the two will turn the turbine. The higher the taller chimney, the greater the pressure difference. This works with or without a jet stream type phe
  • In addition to half-submerged loose containers, which infest navigable waters nowadays, we will have these generators, drifting around after a storm.

    Damage to boats, caused by these extremely dangerous items in the oceans, will cancel environmental gains thousand times over.
  • So ridiculous (Score:4, Interesting)

    by Ancient_Hacker ( 751168 ) on Saturday July 04, 2009 @09:02AM (#28579531)

    These well-meaning schemes still founder on the basic problems of working in a salt-water environment and the issue of a very dilute energy source.
    You can't make a generator that works directly off ocean-swells-- the swells come by so slowly you'd need a coil inductance of about ten thousand Henries.

      A simple loop of wire, as postulated, has about a millionth of that.

    Plus you need considerable iron to channel the magnetic flux. No way around it.

    Regarding the kites, figure out what the very lightest generator weighs, per watt. Hint: not under 30 kilos per KW. Now assume you want to power 100 houses, say 50 KW.
      Figure out the size of the kite needed to lift than many tons. Now at a 30 degree kitestring angle, the pull on the string will be twice the weight of the kite. Figure out how
    much 60,000 feet of kite string that will take that kind of stress weighs. Now you need another large kite just to hold up the kite string.

    And BTW, the "high speed" winds up there are not a panacea. They're high speed but low in density. The energy is, again, very dilute. You need to at least double the size of the kite to get the same amount of lift and pull as you can get at low altitudes.

    • by Weh ( 219305 )

      I'm not an expert on electro-magnetism but I know a bit about ocean waves. The swell typically has a period in the range of 5-15 seconds depending on location and depth, taking into consideration the wave height you can easily work out that there will be a fair bit of variation/acceleration at the buoy. Also, keep in mind that the waves generally aren't regular waves but part of a seastate that consists of various components with different periods, heights and directions. Personally I don't expect much from

  • Fuck it (Score:5, Insightful)

    by ae1294 ( 1547521 ) on Saturday July 04, 2009 @09:08AM (#28579559) Journal

    I say we just keep burning old tires to heat our homes and be done with it...

    I'm sick of all the bogus reasons people come up with why something isn't going to work when they have no fucking idea what the are talking about.

    It's not cost effective - No shit because no one is making 50 million of them yet.
    It's going to change the weather - Ahh yeah and so does standing outside on a windy day jackass.
    It's going to hurt the sea life - Ahh yeah and so does all the trash we dump in the ocean every day and don't forget about all the dead zones from algae overgrowth caused by fertilizer and raw sewage.

    Get some fucking prospective people.. We already are killing the planet.

    Step 1 is to learn to kill it sloooower.
    Step 2 is improve step on step 1.
    Step 3 is to get the fuck out of here.
    Step 4 ????
    Step 5 Profit FOREVER.

  • I think the idea of lifting a generator on a kite is absurd, however, the Ladder mill concept, or any other scheme involving a reciprocating airfoil or flight path can be utilized by a generator on the ground to take advantage of variations on the tension of the tether to generate electricity. []
  • I'm surprised this was brought up publicly because everyone knows the CIA is hell bent to make sure any carbon neutral energy source never takes hold. It's oil and war forever for us, baby.
  • With a 1MW trial set for next year.


  • Ya know the old trick of putting a square of paper on a kite string so it rides up the string to the top?
    (Also done more elaborately so it drops a parachute toy once it hits a trigger at the top, or carries a candle up at night, and many other variations).

    I'd love to see huge "flying wing" kites tethered at 30K feet -- that'd mean tether material strong enough to handle the forces involved (or else when the string breaks it drags across Oregon from Portland to Pocatello tearing up everything in between, bef

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