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Re: Selsam's Myth- "nobody knows how to generate any power with kites"

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  • Doug
    I should clarify my statement: YES people have showed that energy CAN be made using kites. Obviously, you can start with hanging a windmill from a kite and it
    Message 1 of 7 , Nov 4, 2010
      I should clarify my statement:
      YES people have showed that energy CAN be made using kites.
      Obviously, you can start with hanging a windmill from a kite and it will make power.
      Of course that would be too simple for most anyway.

      But what has NOT been developed is:
      a reliable flying wind energy system
      a flying wind energy system that can be left unattended
      a flying wind energy system that works every day when it is windy, i.e. is self-deploying
      a flying wind energy system that produces a useful amount of power at an economical price
      a wind energy system that can work in any mode besides a human-attended, brief demo
      The essence of what I'm trying to get across here to this beginner, asking for "instructions" is that he already knows as much as anyone else.

      BUT
      I have an alternative:
      Dave Santos can explain to this newbie how it is done.
      Dave S., please explain to our new friend, living in Mexico, how airborne wind energy is best done - send him some instructions on how to use a kite to get a reliable and useful amount of energy from the wind, on a consistent basis, and I will bow out and leave it alone.
      Later you can explain the longevity of the system and the economics.

      Meanwhile, to our new member I say this:
      You have built and run several turbines.
      You understand that the power comes from hard blades with airfoils at a flat pitch, traveling at over 100 mph.
      You already know that the "making power" part is the easy part.
      You already know that protection from high winds is the real challenge for any wind energy system.
      You already know that reliable daily operation without human attention is the only workable result.
      That is what nobody has achieved in this field.

      If you want to have someone explain to you that a kite pulls on its line, that the line could therefore drive a winch in pull-out mode, that the kite could then be adjusted to have less pull, that the winch could then use some of the power to pull the line back in, then the cycle repeats - if that is what you want to hear, then you are in the right place.

      On the other hand, if you want to use propellers, even a propeller mounted on a kite, then you will find a few people here who do that, but that is mostly being done by the well-financed players such as Makani and Joby, who do not participate on this list.

      Even Honeywell had an entry in the airborne wind energy conference, but it turned out to be a rendering, and nobody from Honeywell participates in this list either.

      After Dave S. Explains to you how to do airborne wind energy, using reels and winches and kites, imagine the system he explains NOT airborne, but mounted above the ground on support(s). Ask yourself if it seems like a workable system. Ask yourself if such a system could provide a useful amount of power for the cost, and if the intermittent nature of the operation and a portion of the cycle that USES power instead of making power is acceptable, compared to all working systems that provide continuous power.

      Anyway my main message, and one I've said before, is that airborne wind energy is a subset of wind energy and to ignore all that has come before is to start over, making all the mistakes made over 3000 years of wind energy development. Most of the kite-flyers are at the stage of development wind energy reached 2000 years ago, when rectangular sails traveling downwind were replaced by triangular sails traveling across the wind.

      Most of these folks here just figured out within the last YEAR that travel ACROSS the wind has advantages.
      I don't think most still even appreciate that reality. Imagine if your wind turbine used paddles traveling downwind then upwind instead of blades spinning - how much more material would be used to gather how much less power?

      Most do not appreciate the amount of power lost when traveling downwind. Most would like to gloss over the power-draining uptake cycle as though it hardly matters if your system is not working half the time, using power rather than making power.

      In short, without any economic standards of performance to meet, it is easy to say you have the makings of a working system, however at this time there is no system you can buy and run day after day unattended, despite millions and millions of dollars thrown at it.

      And with all those millions thrown at it, there is no system that produces an economically useful amount of power for any use, from any system. Hey all I'm saying is apply the normal standards that you apply to any other wind energy system, and you don't HAVE what would normally be considered a working system.

      Yes of course a kite pulling on its string can be demonstrated to produce some energy, since E=force x distance - that could be accomplished by a simple thought experiment. The question is, how to make it consistent and useful, and nobody has yet achieved that.

      :)
      Doug Selsam
      Doug@...



      --- In AirborneWindEnergy@yahoogroups.com, dave santos <santos137@...> wrote:
      >
      >
      > �
      > Doug is clearly mistaken that "nobody knows how to generate any power with kites". The evidence�is compelling-
      > �
      > KiteGen's record of 40kw�out is several years old.
      > >�
      > >Several teams have shown successful�10kw class experiments (TUDelft, Ampx, Makani, Windlift, etc.)
      > >�
      > >KiteShip & SkySails are able to pull ships with kites. Oceans & continents have been criss-crossed�by kite vehicles.
      > >�
      > >KiteLab has made power by most of the known methods in self-flying versions since 2007.
      > >�
      > >Many small developers are showing power production�is�simple�with hobby kites (Ortho, Skymill, school teams).
      > >�
      > One could go on....
      > �
      > �
      > The back-story is Doug's history of this�particular red-herring claim. If moderated�for�the willful inaccuracy he claims�to be�"censored". The moderators of this list have�resolved Doug will not be able to accuse this particular�list of censorship, but instead face�consistent principled rebuttal like this.
      > �
      > Doug�will continue to be�asked to�properly critique claims of "generating power with kites", & also to follow his own advice of "less talk" without actual results of tapping upper winds.
      > �
      > ===============
      > �
      > Of course, what the BEST ways to make kite power are is still an open study.
      > �
      > A toy-scale demo of just one of the many ways known to generate kite power-
      > �http://www.energykitesystems.net/DaveSantos/tripodtether.mpg
      >
    • Joe Faust
      Several years ago Kitemotor by DaveS working making power. In the photo, is a lifter kite with its tail on the right. A different kite s tail is intruding
      Message 2 of 7 , Nov 4, 2010

        Several years ago Kitemotor by DaveS working making power.  In the photo, 
        is a lifter kite with its tail on the right.    A different kite's tail is intruding from 
        the left of the image.   The turbine is a skygen demonstrator. Scalable.
         

      • Theo Schmidt
        dave santos schrieb: ... This is perhaps the easiest and most practical method so far, but it is a specialist use. I have used kite boats myself; for example
        Message 3 of 7 , Nov 4, 2010
          dave santos schrieb:
          ...
          > KiteShip & SkySails are able to pull ships with kites. Oceans &
          > continents have been criss-crossed by kite vehicles.

          This is perhaps the easiest and most practical method so far, but it is a
          specialist use. I have used kite boats myself; for example pulled a 30 ft.
          sailing yacht with a single Flexifoil with 4 m span (and I have a stack of six),
          and my friends and I have buit a number of solar-powered electric boats of
          similar size, but lighter.

          Now the electric boats could also use the water propeller and motor to generate
          a few kW in favorable winds, using the kites, thus charging the batteries even
          with no sun or solar panels. The propeller is the wrong way around, but will
          still work. I never did this, but there is no reason why it wouldn't work.

          Theo Schmidt
        • Doug
          Theo: Yeah and you could also add a long cable so the boat pulls a car, and have the car pull a donkey, have the Donkey pull a cart, and have the cart pulled
          Message 4 of 7 , Nov 5, 2010
            Theo:
            Yeah and you could also add a long cable so the boat pulls a car, and have the car pull a donkey, have the Donkey pull a cart, and have the cart pulled up a hill, and have Dave Santos get in the cart at the top of the hill and then ride it down with a generator attached to the wheels and charge a cel phone.
            How 'bout that? The Rube Goldberg high-flying cel-phone charger - most expensive/unreliable method yet developed to charge your phone.
            Could we add some aprings? magnets? a feather boa?
            Is there one working anywhere in the world today?
            :)
            Doug S.

            --- In AirborneWindEnergy@yahoogroups.com, Theo Schmidt <theosch06@...> wrote:
            >
            > dave santos schrieb:
            > ...
            > > KiteShip & SkySails are able to pull ships with kites. Oceans &
            > > continents have been criss-crossed by kite vehicles.
            >
            > This is perhaps the easiest and most practical method so far, but it is a
            > specialist use. I have used kite boats myself; for example pulled a 30 ft.
            > sailing yacht with a single Flexifoil with 4 m span (and I have a stack of six),
            > and my friends and I have buit a number of solar-powered electric boats of
            > similar size, but lighter.
            >
            > Now the electric boats could also use the water propeller and motor to generate
            > a few kW in favorable winds, using the kites, thus charging the batteries even
            > with no sun or solar panels. The propeller is the wrong way around, but will
            > still work. I never did this, but there is no reason why it wouldn't work.
            >
            > Theo Schmidt
            >
          • Theo Schmidt
            ... You don t seem to get it! ;-) In the environment of a boat with *no* cable going ashore, every little bit of energy is valuable so it commands a far higher
            Message 5 of 7 , Nov 5, 2010
              Doug schrieb:
              > Theo: Yeah and you could also add a long cable so the boat pulls a
              > car, and have the car pull a donkey,...

              You don't seem to get it! ;-) In the environment of a boat with *no*
              cable going ashore, every little bit of energy is valuable so it
              commands a far higher price than ashore. People spend large sums of
              money for relatively weak and heavy marine engines, generators and even
              combined-heat-and-power Stirling generator/heaters. Or solar panels or
              wind generators, both of which are limited in size with the rigging of
              most sailing yachts.

              Now with kites you are much less limited in size. While not practical in
              a marina or a tight mooring, there is no problem flying a kite at anchor
              or when under way.

              Sailing yachts are quite heavy so carrying lead storage batteries is not
              a big deal, they can even double as ballast. If you have a wind
              generator *and* some solar cells *and* a water generator (some
              windgenerators have a conversion kit, basically a towed screw), and an
              electric inboard or outboard motor, you don't need any combustion
              engines and can still keep going in any direction in most conditions
              while at the same time powering your onboard electric stuff. You can fly
              kites on sailing yachts in spite of the rigging, but it is only fun on
              those with unstayed masts like junk-rigged boats.

              I've done all the above, just not at the same time. No donkeys needed.

              Cheers, Theo

              PS Kiteboarding has become quite popular these days. Now if you think
              that the sort of person who kiteboards or windsurfs might be prone to
              using those dreadful jetski things or waterski behind powerboats, if
              kiteboards or sailboards didn't exist. Thus the kites are indirectly
              generating power by *saving* this power (concept of Negawatts).
            • Doug
              Theo: Clearly what you say is so compelling, with the amount of energy you can generate, and the high price it will command offshore , why waste one more
              Message 6 of 7 , Nov 6, 2010
                Theo:
                Clearly what you say is so compelling, with the amount of energy you can generate, and the high price it will command "offshore", why waste one more second talking about it on this list when you could be raking in all those dollars?
                :)
                Doug S.

                --- In AirborneWindEnergy@yahoogroups.com, Theo Schmidt <theosch06@...> wrote:
                >
                > Doug schrieb:
                > > Theo: Yeah and you could also add a long cable so the boat pulls a
                > > car, and have the car pull a donkey,...
                >
                > You don't seem to get it! ;-) In the environment of a boat with *no*
                > cable going ashore, every little bit of energy is valuable so it
                > commands a far higher price than ashore. People spend large sums of
                > money for relatively weak and heavy marine engines, generators and even
                > combined-heat-and-power Stirling generator/heaters. Or solar panels or
                > wind generators, both of which are limited in size with the rigging of
                > most sailing yachts.
                >
                > Now with kites you are much less limited in size. While not practical in
                > a marina or a tight mooring, there is no problem flying a kite at anchor
                > or when under way.
                >
                > Sailing yachts are quite heavy so carrying lead storage batteries is not
                > a big deal, they can even double as ballast. If you have a wind
                > generator *and* some solar cells *and* a water generator (some
                > windgenerators have a conversion kit, basically a towed screw), and an
                > electric inboard or outboard motor, you don't need any combustion
                > engines and can still keep going in any direction in most conditions
                > while at the same time powering your onboard electric stuff. You can fly
                > kites on sailing yachts in spite of the rigging, but it is only fun on
                > those with unstayed masts like junk-rigged boats.
                >
                > I've done all the above, just not at the same time. No donkeys needed.
                >
                > Cheers, Theo
                >
                > PS Kiteboarding has become quite popular these days. Now if you think
                > that the sort of person who kiteboards or windsurfs might be prone to
                > using those dreadful jetski things or waterski behind powerboats, if
                > kiteboards or sailboards didn't exist. Thus the kites are indirectly
                > generating power by *saving* this power (concept of Negawatts).
                >
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