Loading ...
Sorry, an error occurred while loading the content.
 

Re: [AWES] Re: Forging ahead despite ignorance, lack of help

Expand Messages
  • dave santos
    Phil,   The Kingfisher aerostat, as well as blimps generally, are far more expensive, for a given amount of lift, than simple kites. The proposed 1000sqft
    Message 1 of 13 , Mar 14, 2012
      Phil,
       
      The Kingfisher aerostat, as well as blimps generally, are far more expensive, for a given amount of lift, than simple kites. The proposed 1000sqft lifter-kite* to raise Doug's next HAWT is a rope-loadpath multi-tarp design that can be quickly rigged with about $100 of materials, and can lift around 500lbs (depending on windspeed). So the Kingfisher is about 100 times more expensive by capital cost to lift ratio, and far higher operational cost as well. I worked with helium LTA for many years, and consider it a dead-end for major AWE applications, for a long list of reasons already covered on the Forum (storm survival; helium conservation, leakage, and availability, etc.).
       
      Classifying AWES defies any simple ontology. I find that multi-kite/multi-anchor systems are the most scalable, with an open choice of power-harvesting units (many viable options like traction rotors, wingmills, varidrogues are overlooked). These architectural realms are absent from simplistic AWES classifications.
       
      Don't get discouraged though, all of the "cold water" above is actually good news; of more design options, for more power, at lower cost, than commonly supposed,
       
      daveS
       
      * It need not be quite this big, but the low-wind capability can be totally superior to the same turbine stuck idly in surface calm. One does need to launch thru surface calm, perhaps by pilot-kite stages or step-towing; the prize of upper-wind clearly requires greater effort to master.
          
    • Phils
      Hi Dave, Yes I agree. My thoughs were The Inital Lift to Height for reaching wind speed to sustain kite lift for the payload, then Decouple the King
      Message 2 of 13 , Mar 14, 2012
        Hi Dave, Yes I agree.
        My thoughs were The Inital Lift to Height for reaching wind speed to sustain kite lift for the payload, then Decouple the King Fisher, for reuse.
        The king Fisher as you may know likes to maintain a near vertical lift profile in winds, instead of listing down range which eats up realestate. Consider it a reuseable launch vehical
        The lift gas would be Hydrogen for this application. That could be made on site at the down drop for the substations.


        --- In AirborneWindEnergy@yahoogroups.com, dave santos <santos137@...> wrote:
        >
        > Phil,
        >  
        > The Kingfisher aerostat, as well as blimps generally, are far more expensive, for a given amount of lift, than simple kites. The proposed 1000sqft lifter-kite* to raise Doug's next HAWT is a rope-loadpath multi-tarp design that can be quickly rigged with about $100 of materials, and can lift around 500lbs (depending on windspeed). So the Kingfisher is about 100 times more expensive by capital cost to lift ratio, and far higher operational cost as well. I worked with helium LTA for many years, and consider it a dead-end for major AWE applications, for a long list of reasons already covered on the Forum (storm survival; helium conservation, leakage, and availability, etc.).
        >  
        > Classifying AWES defies any simple ontology. I find that multi-kite/multi-anchor systems are the most scalable, with an open choice of power-harvesting units (many viable options like traction rotors, wingmills, varidrogues are overlooked). These architectural realms are absent from simplistic AWES classifications.
        >  
        > Don't get discouraged though, all of the "cold water" above is actually good news; of more design options, for more power, at lower cost, than commonly supposed,
        >  
        > daveS
        >  
        > * It need not be quite this big, but the low-wind capability can be totally superior to the same turbine stuck idly in surface calm. One does need to launch thru surface calm, perhaps by pilot-kite stages or step-towing; the prize of upper-wind clearly requires greater effort to master.    
        >
      • Phils
        Sorry , forgot to scrub the replyed message. I m learning. 8)
        Message 3 of 13 , Mar 14, 2012
          Sorry , forgot to scrub the replyed message.
          I'm learning. 8)
        • Phils
          The second prospect of using the king fisher could be as a assist lift. Say if the winds at height are forcast to die out enough that the kite could not
          Message 4 of 13 , Mar 14, 2012
            The second prospect of using the king fisher could be as a assist lift. Say if the winds at height are forcast to die out enough that the kite could not support the payload. The king Fisher could be ran up the tether, coupled, and remain aloft supporting the kite and payload until the winds pick back up . Or,It is ran up, coupled, and the whole system is brought down in a near vertical fashion.
            Where as the kite alone could crash down if it got low enough to not generate any lift any more .
          • dave santos
            Phil,   Nobody has solved hydrogen problems (explosivity with even small amounts of air contamination, highest leakage rate with ozone layer depletion, high
            Message 5 of 13 , Mar 14, 2012
              Phil,
               
              Nobody has solved hydrogen problems (explosivity with even small amounts of air contamination, highest leakage rate with ozone layer depletion, high chemical reactivity, etc). No one has solved LTA storm survival, except by a hangar or deflation requirement. No one has beaten the standard streamlined blimp design for general performance (static and dynamic Lift v. Drag) although some kytoons have desirable capability.
               
              We also know how to keep kites up in calm by pumping the line, especially by phased circular or step-tow tugs, and we can land them reliably in no wind by reeling them in under control. LTA for holding up idle AWES equipment during calm periods does not contribute much value.
               
              Of course hundreds of such issues were well explored in the prior 5000 Forum messages, not to mention Joe Faust's volumes of AWE content, but data-mining a mountain is not easy   :)
               
              daveS
               
              PS You have added a corollary observation to the LTA topic- that the cheapest maximal-volume round balloon is good enough for assisted launch in low wind, even if very unsuited for any high-wind role.  KiteLab has used single party balloons as the initial pilot-lift basis for staged launch of kite arrays: In principle no more LTA than that is really needed for vast kite farm operations.

               
                  
            • Phils
              It s Ground already covered. Ok, I ll dabble in another direction. It s windy today here ,Think I ll go fly my kites 8)
              Message 6 of 13 , Mar 14, 2012
                It's Ground already covered. Ok, I'll dabble in another direction. It's windy today here ,Think I'll go fly my kites 8)
              • Doug
                Don t you have something a little better than blue tarps at the world kite museum? (affordable though...) We re not talking about lifting several tons here.
                Message 7 of 13 , Mar 15, 2012
                  Don't you have something a little better than blue tarps at the world kite museum? (affordable though...) We're not talking about lifting several tons here. I can take steps to make a lightweight generator. Often in wind energy you try to make certain components heavier, rather than lighter, on the principle of "The 3 Little Pigs" which is a scientific theory only taught at the highest levels of academia, but I think I have some room to lighten a generator significantly and it should last days, months or more.
                  What kite options do we have to lift something between, say 50 and 100 lbs, that will stay up when the wind gets a bit light? What about lifting say 20 or 30 lbs?
                  :)
                  Doug S.

                  --- In AirborneWindEnergy@yahoogroups.com, dave santos <santos137@...> wrote:
                  >
                  > Phil,
                  > �
                  > The Kingfisher aerostat, as well as blimps generally, are far�more expensive, for a given amount of lift, than simple kites.�The proposed�1000sqft lifter-kite* to raise Doug's next HAWT is a rope-loadpath multi-tarp design that can be quickly rigged�with about $100 of materials, and can lift around 500lbs (depending on windspeed). So the Kingfisher is about 100 times more expensive by capital cost to lift ratio, and far higher operational cost as well. I worked with helium LTA for many years, and consider it a dead-end for major AWE applications, for a long list of reasons already covered on the Forum (storm survival; helium conservation, leakage, and availability, etc.).
                  > �
                  > Classifying AWES defies any simple ontology. I find that multi-kite/multi-anchor systems are the most scalable,�with an open�choice of power-harvesting units (many viable options�like traction rotors, wingmills, varidrogues are overlooked). These architectural realms are�absent from simplistic AWES�classifications.
                  > �
                  > Don't get discouraged though, all of the "cold water"�above is actually good news; of more design options, for more power,�at lower cost, than commonly supposed,
                  > �
                  > daveS
                  > �
                  > * It need not be quite this big, but the low-wind capability�can�be totally superior to�the same�turbine�stuck idly�in�surface calm. One does need to�launch thru surface calm, perhaps by�pilot-kite stages or�step-towing;�the prize of upper-wind clearly requires greater effort to master.����
                  >
                Your message has been successfully submitted and would be delivered to recipients shortly.