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Rim Driven Wind Turbine (RDWT),drag-based and lift-based blades

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  • Pierre Benhaiem
    A question for Doug, Project TTU « Keuka Energy claims its RDWT with 16 drag-based blades gives a very
    Message 1 of 26 , Oct 11, 2012

      A question for Doug,

      Project TTU « Keuka Energy claims its RDWT with 16 drag-based blades gives a very high value of efficiency with wind speed = 10 m/s.Diameter being 7.62 m,swept area is 45 m²  and power is more than 14 kW on the blue curve on Wind Energy - University of New Mexico.The resulting  value seems very high:52% (Betz limit being 59%),so high as value of lift-based blades, comprising that of Barber Wind (another RDWT with lift-based five blades).

      Do you think such a high value is possible for drag-based blades?

      For my knowledge the higher value for drag-based blades concerns multiblade American pumping (about 30%).

      I do not think you like these sorts of designs and calculations from another Pr.Crackpot,but your answer can be useful, above all if the given value of these drag-based blades is too high and looks really impossible.

      Pierre B

      Airborne Seaborne Wind Energy System (another RDWT),yet another this time completely Airborne Flygen RDWT being that described on Dr. Beaujean' paper. 

       

    • Pierre BENHAIEM
      More complete datas (which diameter being 7.62 m,see page 28) on joined paper. PierreB ... More complete datas (which diameter being 7.62 m,see page 28) on
      Message 2 of 26 , Oct 11, 2012


      More complete datas (which diameter being 7.62 m,see page 28) on joined paper.

       

      PierreB



      > Message du 12/10/12 03:33
      > De : "Pierre Benhaiem"
      > A : AirborneWindEnergy@yahoogroups.com
      > Copie à :
      > Objet : [AWES] Rim Driven Wind Turbine (RDWT),drag-based and lift-based blades
      >
      >  

      >

      > A question for Doug,

      > Project TTU « Keuka Energy claims its RDWT with 16 drag-based blades gives a very high value of efficiency with wind speed = 10 m/s.Diameter being 7.62 m,swept area is 45 m²  and power is more than 14 kW on the blue curve on Wind Energy - University of New Mexico.The resulting  value seems very high:52% (Betz limit being 59%),so high as value of lift-based blades, comprising that of Barber Wind (another RDWT with lift-based five blades).

      > Do you think such a high value is possible for drag-based blades?

      > For my knowledge the higher value for drag-based blades concerns multiblade American pumping (about 30%).

      > I do not think you like these sorts of designs and calculations from another Pr.Crackpot,but your answer can be useful, above all if the given value of these drag-based blades is too high and looks really impossible.

      > Pierre B

      Airborne Seaborne Wind Energy System (another RDWT),yet another this time completely Airborne Flygen RDWT being that described on Dr. Beaujean' paper. 

      >  

    • dave santos
      Pierre, Your question to Doug somehow presupposed Keuka s blades are drag based . They are fully lift-based (force orthogonal to flow), they just have a lower
      Message 3 of 26 , Oct 11, 2012
        Pierre,

        Your question to Doug somehow presupposed Keuka's blades are "drag based".

        They are fully lift-based (force orthogonal to flow), they just have a lower L/D ~10 instead of ~100 for conventional designs. Even with this added drag it can still deliver high Betz efficiency at certain speeds. The rim-drive helps generator rpm be quite high, even with a very low TSR.

        Such a design can be roughly comparable in overall performance with hi L/D turbines, but market and operational factors count. It is advantaged in lower winds, but disadvantaged in high winds. Its easier to service and less of a risk to birds. Perhaps this old 70s "rim-drive" approach can evolve into a real contender, not just an also-ran,

        daveS
      • Doug
        ... *****Some might call that a drag machine because it has so many blades (high rotor solidity) but I think it still uses lift. You have to be careful
        Message 4 of 26 , Oct 11, 2012
          --- In AirborneWindEnergy@yahoogroups.com, "Pierre Benhaiem" <pierre.benhaiem@...> wrote: > A question for Doug,
          > Project TTU � Keuka Energy
          > <http://www.keukaenergy.com/case-studies/project-2/> claims its RDWT> with 16 drag-based blades gives a very high value of efficiency with> wind speed = 10 m/s.Diameter being 7.62 m,swept area is 45 m�
          *****Some might call that a drag machine because it has so many blades (high rotor solidity) but I think it still uses lift. You have to be careful believing such power output statistics. They may take one moment when it got a big gust and extrapolate. They never talk about the bad news. It's easy to get a turbine without overspeed protection to look like a rock star for a while, making ridiculously high amounts of power in big gusts, til eventually it burns out. These promotional statistics and probably way overestimated of the data was cherry-picked from a set that had in totality reflected lower performance - just a guess - "when it sounds too good..."

          University
          > of New Mexico <http://www.unm.edu/~poroseva/windenergy/> .The resulting
          > value seems very high:52% (Betz limit being 59%),so high as value of
          > lift-based blades, comprising that of Barber Wind
          > <http://barberwind.net/> (another RDWT with lift-based five blades).
          *******OK great Barber wind -5 blades is two blades too many - of course they are going to conquer the world.

          > Do you think such a high value is possible for drag-based blades?
          *****Not really. A good windmill gets a Cp of like 30% if you are lucky. And drag windmills usually do less.
          The farm pumper is marginally a drag machine - a matter of opinion to some extent I think, and I am really not sure of the efficiency but they never work out well for generating electricity and of course many have tried.
          Maybe drag could work for some kind of AWE since swept area is unlimited. In general though you want speed to generate electricity - nothing like fast blades to spin a generator and it is still never as fast as you would like and you need a special low speed generator even using lift - drag gets far worse.*********

          > For my knowledge the higher value for drag-based blades concerns
          > multiblade American pumping (about 30%).
          >
          > I do not think you like these sorts of designs and calculations from
          > another Pr.Crackpot,but your answer can be useful, above all if the
          > given value of these drag-based blades is too high and looks really
          > impossible
          ************Profethor Crackpot!?!?!?#%$*&$(%_%+#Y#)(*+@
          >
          > Pierre B
          >
          > Airborne Seaborne Wind Energy System <http://wheelwind.com/> (another
          > RDWT),yet another this time completely Airborne Flygen RDWT being that
          > described on Dr. Beaujean' paper.
          >
        • Pierre BENHAIEM
          DaveS, Thank for precisions.The paper CAPS 2010 Report: Celebrating Ten Years of Research precises in page 61 ...(RDWT) is a new concept in drag-based wind
          Message 5 of 26 , Oct 12, 2012


            DaveS,

             

            Thank for precisions.The paper CAPS 2010 Report: Celebrating Ten Years of Research precises in page 61 "...(RDWT) is a new concept in drag-based wind turbines...".Indeed blades look like old American drag (with a little lift component?)-based (TSR at better value being 1) multiblade pumping,and given efficiency seems very very high (identical or more than lifted-based).

             

            The following link ISBN 978-1-4507-9223-3 - ASME Global Communities goes to the precedent pdf attachment.

             

            PierreB

             





             

            > Message du 12/10/12 04:21
            > De : "dave santos"
            > A : "AirborneWindEnergy@yahoogroups.com"
            > Copie à :
            > Objet : Re: [AWES] Rim Driven Wind Turbine (RDWT),drag-based and lift-based blades
            >
            >  

            >

            Pierre,

            >
            Your question to Doug somehow presupposed Keuka's blades are "drag based".

            >
            They are fully lift-based (force orthogonal to flow), they just have a lower L/D ~10 instead of ~100 for conventional designs. Even with this added drag it can still deliver high Betz efficiency at certain speeds. The rim-drive helps generator rpm be quite high, even with a very low TSR.

            >
            Such a design can be roughly comparable in overall performance with hi L/D turbines, but market and operational factors count. It is advantaged in lower winds, but disadvantaged in high winds. Its easier to service and less of a risk to birds. Perhaps this old 70s "rim-drive" approach can evolve into a real contender, not just an also-ran,

            >
            daveS
          • Pierre BENHAIEM
            Doug, Thanks for indications.Concerning lift use your analysis joins DaveS analysis about multi blades.But blades from Barberwind look more as
            Message 6 of 26 , Oct 12, 2012


              Doug,

               

              Thanks for indications.Concerning lift use your analysis joins DaveS' analysis about multi blades.But blades from Barberwind look more as lifted-based.

              "The farm pumper is marginally a drag machine - a matter of opinion to some extent I think, and I am really not sure of the efficiency but they never work out well for generating electricity and of course many have tried."

              - Among other things in good conditions Tip Speed Ratio of farm pumper is only 1,too low for working by the axis a 1500 rpm conventional generator without a big gearbox.But with Rim Driven it can be different.

               

              "5 blades is two blades too many".

              - It is possible Barberwind and other firms use more blades for their RDWT for a structural reason,blades being also like spokes,being set on cross cables,but I am not sure of it.Another thing is that a too high Tip Speed would be a problem for wheel transmission and also for aerodynamic efficiency (losses by Rim),but I am aslo not sure of it.Profils of blades should be different with a rim (I put a ring (section 2 cm) arround a propeller (diameter 50 cm):alone the propeller turns fast,but with ring it does not turn;perhaps the tip speed should be larger,but I am not sure of it. 
               

              "Maybe drag could work for some kind of AWE since swept area is unlimited".I look again what author writes it and see the author is not DaveS but Doug!

               

              Note:the potential Pr.Crackpot could be the scientists which make calculations,in sense I supposed rightly or wrongly to be yours.

               

              PierreB

              > Message du 12/10/12 05:27
              > De : "Doug"
              > A : AirborneWindEnergy@yahoogroups.com
              > Copie à :
              > Objet : [AWES] Re: Rim Driven Wind Turbine (RDWT),drag-based and lift-based blades
              >
              >  

              >
              >
              > --- In AirborneWindEnergy@yahoogroups.com, "Pierre Benhaiem" wrote: > A question for Doug,
              > > Project TTU � Keuka Energy
              > > <http://www.keukaenergy.com/case-studies/project-2/> claims its RDWT> with 16 drag-based blades gives a very high value of efficiency with> wind speed = 10 m/s.Diameter being 7.62 m,swept area is 45 m�
              > *****Some might call that a drag machine because it has so many blades (high rotor solidity) but I think it still uses lift. You have to be careful believing such power output statistics. They may take one moment when it got a big gust and extrapolate. They never talk about the bad news. It's easy to get a turbine without overspeed protection to look like a rock star for a while, making ridiculously high amounts of power in big gusts, til eventually it burns out. These promotional statistics and probably way overestimated of the data was cherry-picked from a set that had in totality reflected lower performance - just a guess - "when it sounds too good..."
              >
              > University
              > > of New Mexico <http://www.unm.edu/~poroseva/windenergy/> .The resulting
              > > value seems very high:52% (Betz limit being 59%),so high as value of
              > > lift-based blades, comprising that of Barber Wind
              > > <http://barberwind.net/> (another RDWT with lift-based five blades).
              > *******OK great Barber wind -5 blades is two blades too many - of course they are going to conquer the world.
              >
              > > Do you think such a high value is possible for drag-based blades?
              > *****Not really. A good windmill gets a Cp of like 30% if you are lucky. And drag windmills usually do less.
              > The farm pumper is marginally a drag machine - a matter of opinion to some extent I think, and I am really not sure of the efficiency but they never work out well for generating electricity and of course many have tried.
              > Maybe drag could work for some kind of AWE since swept area is unlimited. In general though you want speed to generate electricity - nothing like fast blades to spin a generator and it is still never as fast as you would like and you need a special low speed generator even using lift - drag gets far worse.*********
              >
              > > For my knowledge the higher value for drag-based blades concerns
              > > multiblade American pumping (about 30%).
              > >
              > > I do not think you like these sorts of designs and calculations from
              > > another Pr.Crackpot,but your answer can be useful, above all if the
              > > given value of these drag-based blades is too high and looks really
              > > impossible
              > ************Profethor Crackpot!?!?!?#%$*&$(%_%+#Y#)(*+@
              > >
              > > Pierre B
              > >
              > > Airborne Seaborne Wind Energy System <http://wheelwind.com/> (another
              > > RDWT),yet another this time completely Airborne Flygen RDWT being that
              > > described on Dr. Beaujean' paper.
              > >
              >
              >

            • Pierre BENHAIEM
              Correction, the tip speed should be larger,but I am not sure of it. . The tip of the blade (not tip speed of course). PierreB ... Correction, the tip speed
              Message 7 of 26 , Oct 12, 2012


                Correction,

                 

                " the tip speed should be larger,but I am not sure of it.". The tip of the blade (not tip speed of course).

                 

                PierreB



                > Message du 12/10/12 10:43
                > De : "Pierre BENHAIEM"
                > A : AirborneWindEnergy@yahoogroups.com
                > Copie à :
                > Objet : re: [AWES] Re: Rim Driven Wind Turbine (RDWT),drag-based and lift-based blades
                >
                >  

                >

                >
                > Doug,

                >  

                > Thanks for indications.Concerning lift use your analysis joins DaveS' analysis about multi blades.But blades from Barberwind look more as lifted-based.

                > "The farm pumper is marginally a drag machine - a matter of opinion to some extent I think, and I am really not sure of the efficiency but they never work out well for generating electricity and of course many have tried."

                > - Among other things in good conditions Tip Speed Ratio of farm pumper is only 1,too low for working by the axis a 1500 rpm conventional generator without a big gearbox.But with Rim Driven it can be different.

                >  

                > "5 blades is two blades too many".

                > - It is possible Barberwind and other firms use more blades for their RDWT for a structural reason,blades being also like spokes,being set on cross cables,but I am not sure of it.Another thing is that a too high Tip Speed would be a problem for wheel transmission and also for aerodynamic efficiency (losses by Rim),but I am aslo not sure of it.Profils of blades should be different with a rim (I put a ring (section 2 cm) arround a propeller (diameter 50 cm):alone the propeller turns fast,but with ring it does not turn;perhaps the tip speed should be larger,but I am not sure of it. 
                >  

                > "Maybe drag could work for some kind of AWE since swept area is unlimited".I look again what author writes it and see the author is not DaveS but Doug!

                >  

                > Note:the potential Pr.Crackpot could be the scientists which make calculations,in sense I supposed rightly or wrongly to be yours.

                >  

                > PierreB

                > Message du 12/10/12 05:27
                > > De : "Doug"
                > > A : AirborneWindEnergy@yahoogroups.com
                > > Copie à :
                > > Objet : [AWES] Re: Rim Driven Wind Turbine (RDWT),drag-based and lift-based blades
                > >
                > >  

                > >
                > >
                > > --- In AirborneWindEnergy@yahoogroups.com, "Pierre Benhaiem" wrote: > A question for Doug,
                > > > Project TTU � Keuka Energy
                > > > <http://www.keukaenergy.com/case-studies/project-2/> claims its RDWT> with 16 drag-based blades gives a very high value of efficiency with> wind speed = 10 m/s.Diameter being 7.62 m,swept area is 45 m�
                > > *****Some might call that a drag machine because it has so many blades (high rotor solidity) but I think it still uses lift. You have to be careful believing such power output statistics. They may take one moment when it got a big gust and extrapolate. They never talk about the bad news. It's easy to get a turbine without overspeed protection to look like a rock star for a while, making ridiculously high amounts of power in big gusts, til eventually it burns out. These promotional statistics and probably way overestimated of the data was cherry-picked from a set that had in totality reflected lower performance - just a guess - "when it sounds too good..."
                > >
                > > University
                > > > of New Mexico <http://www.unm.edu/~poroseva/windenergy/> .The resulting
                > > > value seems very high:52% (Betz limit being 59%),so high as value of
                > > > lift-based blades, comprising that of Barber Wind
                > > > <http://barberwind.net/> (another RDWT with lift-based five blades).
                > > *******OK great Barber wind -5 blades is two blades too many - of course they are going to conquer the world.
                > >
                > > > Do you think such a high value is possible for drag-based blades?
                > > *****Not really. A good windmill gets a Cp of like 30% if you are lucky. And drag windmills usually do less.
                > > The farm pumper is marginally a drag machine - a matter of opinion to some extent I think, and I am really not sure of the efficiency but they never work out well for generating electricity and of course many have tried.
                > > Maybe drag could work for some kind of AWE since swept area is unlimited. In general though you want speed to generate electricity - nothing like fast blades to spin a generator and it is still never as fast as you would like and you need a special low speed generator even using lift - drag gets far worse.*********
                > >
                > > > For my knowledge the higher value for drag-based blades concerns
                > > > multiblade American pumping (about 30%).
                > > >
                > > > I do not think you like these sorts of designs and calculations from
                > > > another Pr.Crackpot,but your answer can be useful, above all if the
                > > > given value of these drag-based blades is too high and looks really
                > > > impossible
                > > ************Profethor Crackpot!?!?!?#%$*&$(%_%+#Y#)(*+@
                > > >
                > > > Pierre B
                > > >
                > > > Airborne Seaborne Wind Energy System <http://wheelwind.com/> (another
                > > > RDWT),yet another this time completely Airborne Flygen RDWT being that
                > > > described on Dr. Beaujean' paper.
                > > >
                > >
                > >

              • Doug
                Guys: OK I hate to sound like a broken record but... Rim-driven turbine with too many blades verging on drag... 5 blades instead of 3... Hello? Why are we back
                Message 8 of 26 , Oct 12, 2012
                  Guys:
                  OK I hate to sound like a broken record but...
                  Rim-driven turbine with too many blades verging on drag...
                  5 blades instead of 3...
                  Hello?
                  Why are we back here?
                  Just because we are in AWE do we have to always talk like we are ignorant newbies?

                  Honeywell adopted a Professor Crackpot design a few years back.
                  Their "highly-educated" (no doubt PhD) staff looked at:
                  1) Rotor solidity too high
                  2) cloth blades
                  3) rim drive
                  4) recommended for rooftop mounting
                  (hey might as well have ALL the newbie factors right? I mean if you are that STUPID, you might as well completely fulfill your role as a newbie idiot and recommend it for a rooftop too, right?
                  I mean let's make ALL the newbie mistakes combined right? The only typical newbie idiot feature they missed was vertical axis, but I'll bet they were tempted...

                  Guess what happened?
                  Honeywell is a LAUGHINGSTOCK.
                  NOBODY is using this hunk of garbage that
                  a) weighs hundreds of pounds versus say 30 lbs for a competing, superior unit)
                  b) costs way too much for the output
                  Guess what they eliminated?
                  The cloth blades - they decided to use real blades - the cloth ones didn't work out - gee ya think?
                  Can we just be a bit blunt here?
                  If anyone wants to do wind energy, get a book on it and look this stuff up.
                  NO you don't want to use cloth blades, M'Kay?
                  NO there is NO advantage to more than 3 blades, M'Kay? And nobody needs to keep asking that over and over every year or every decade - it was worked out LONG AGO.

                  Why do you see rotors with too many blades? Because of cogging - people make a turbine, realize it has too much cogging to start in light winds, so they add blades to get it spinning. Startup torque. Then they imagine it "needs" or "uses" these extra blades in normal operation.
                  NO they don't "use" the extra blades. What do the extra blades do? They cause drag - they are just along for the ride. Like if you added two more wheels to your car - 4 is all you want!
                  So rather than treat these questions like they are brand new, why not get up to speed on the art by cracking open a book on turbine design?
                  Why act like simple questions with simple answers are some impenetrable mystery?

                  The problem with this group, to me, is this:
                  Imagine a group purporting to be studying advanced mathematics. But the people in the group are asking questions like "I was trying to add a column of numbers and two digits added up to more than 9 and I didn't know what to do with the extra digit!", and someone had to explain how to "carry the remainder" (or however we said it in second grade) and you don't even know how to do simple addition using a pencil, yet you talk about advanced mathematical theory.
                  This sounds like an exaggeration, but it's really an understatement: witness one member whom I will not mention who promotes ALL the disproven newbie ideas combined, and tries to rationalize it by citing buzzwords from advanced quantum physics. You can't make this stuff up!

                  One cannot meaningfully discuss an art without at least a limited introductory background to that art.

                  Why did the "smart" people at Honeywell make this mistake? They just made all the typical idiot newbie mistakes because their PhD's assumed they were SO SMART they didn't need to read the beginning textbook on the actual subject, and the bean-counters and executive decision-makers believed them. Result? Not.
                  :)
                  Doug Selsam



                  --- In AirborneWindEnergy@yahoogroups.com, Pierre BENHAIEM <pierre.benhaiem@...> wrote:
                  >
                  >
                  > Doug, Thanks for indications.Concerning lift use your analysis joins DaveS' analysis about multi blades.But blades from Barberwind look more as lifted-based."The farm pumper is marginally a drag machine - a matter of opinion to some extent I think, and I am really not sure of the efficiency but they never work out well for generating electricity and of course many have tried."- Among other things in good conditions Tip Speed Ratio of farm pumper is only 1,too low for working by the axis a 1500 rpm conventional generator without a big gearbox.But with Rim Driven it can be different. "5 blades is two blades too many".- It is possible Barberwind and other firms use more blades for their RDWT for a structural reason,blades being also like spokes,being set on cross cables,but I am not sure of it.Another thing is that a too high Tip Speed would be a problem for wheel transmission and also for aerodynamic efficiency (losses by Rim),but I am aslo not sure of it.Profils of blades should be different with a rim (I put a ring (section 2 cm) arround a propeller (diameter 50 cm):alone the propeller turns fast,but with ring it does not turn;perhaps the tip speed should be larger,but I am not sure of it.
                  > "Maybe drag could work for some kind of AWE since swept area is unlimited".I look again what author writes it and see the author is not DaveS but Doug! Note:the potential Pr.Crackpot could be the scientists which make calculations,in sense I supposed rightly or wrongly to be yours. PierreB> Message du 12/10/12 05:27
                  > > De : "Doug"
                  > > A : AirborneWindEnergy@yahoogroups.com
                  > > Copie à :
                  > > Objet : [AWES] Re: Rim Driven Wind Turbine (RDWT),drag-based and lift-based blades
                  > >
                  > > >
                  > >
                  > > --- In AirborneWindEnergy@yahoogroups.com, "Pierre Benhaiem" wrote: > A question for Doug,
                  > > > Project TTU � Keuka Energy
                  > > > claims its RDWT> with 16 drag-based blades gives a very high value of efficiency with> wind speed = 10 m/s.Diameter being 7.62 m,swept area is 45 m�
                  > > *****Some might call that a drag machine because it has so many blades (high rotor solidity) but I think it still uses lift. You have to be careful believing such power output statistics. They may take one moment when it got a big gust and extrapolate. They never talk about the bad news. It's easy to get a turbine without overspeed protection to look like a rock star for a while, making ridiculously high amounts of power in big gusts, til eventually it burns out. These promotional statistics and probably way overestimated of the data was cherry-picked from a set that had in totality reflected lower performance - just a guess - "when it sounds too good..."
                  > >
                  > > University
                  > > > of New Mexico .The resulting
                  > > > value seems very high:52% (Betz limit being 59%),so high as value of
                  > > > lift-based blades, comprising that of Barber Wind
                  > > > (another RDWT with lift-based five blades).
                  > > *******OK great Barber wind -5 blades is two blades too many - of course they are going to conquer the world.
                  > >
                  > > > Do you think such a high value is possible for drag-based blades?
                  > > *****Not really. A good windmill gets a Cp of like 30% if you are lucky. And drag windmills usually do less.
                  > > The farm pumper is marginally a drag machine - a matter of opinion to some extent I think, and I am really not sure of the efficiency but they never work out well for generating electricity and of course many have tried.
                  > > Maybe drag could work for some kind of AWE since swept area is unlimited. In general though you want speed to generate electricity - nothing like fast blades to spin a generator and it is still never as fast as you would like and you need a special low speed generator even using lift - drag gets far worse.*********
                  > >
                  > > > For my knowledge the higher value for drag-based blades concerns
                  > > > multiblade American pumping (about 30%).
                  > > >
                  > > > I do not think you like these sorts of designs and calculations from
                  > > > another Pr.Crackpot,but your answer can be useful, above all if the
                  > > > given value of these drag-based blades is too high and looks really
                  > > > impossible
                  > > ************Profethor Crackpot!?!?!?#%$*&$(%_%+#Y#)(*+@
                  > > >
                  > > > Pierre B
                  > > >
                  > > > Airborne Seaborne Wind Energy System (another
                  > > > RDWT),yet another this time completely Airborne Flygen RDWT being that
                  > > > described on Dr. Beaujean' paper.
                  > > >
                  > >
                  > >
                  >
                • Pierre BENHAIEM
                  Can his design http://www.gual-industrie.com/ improve the record in Proof-of-Crackpotness? PierreB ... Can his design http://www.gual-industrie.com/ improve
                  Message 9 of 26 , Oct 12, 2012


                    Can his design http://www.gual-industrie.com/ improve the record in Proof-of-Crackpotness?

                     

                    PierreB


                     


                    > Message du 12/10/12 15:41
                    > De : "Doug"
                    > A : AirborneWindEnergy@yahoogroups.com
                    > Copie à :
                    > Objet : [AWES] Re: Rim Driven Wind Turbine: Honeywell's laughingstock
                    >
                    >  

                    > Guys:
                    > OK I hate to sound like a broken record but...
                    > Rim-driven turbine with too many blades verging on drag...
                    > 5 blades instead of 3...
                    > Hello?
                    > Why are we back here?
                    > Just because we are in AWE do we have to always talk like we are ignorant newbies?
                    >
                    > Honeywell adopted a Professor Crackpot design a few years back.
                    > Their "highly-educated" (no doubt PhD) staff looked at:
                    > 1) Rotor solidity too high
                    > 2) cloth blades
                    > 3) rim drive
                    > 4) recommended for rooftop mounting
                    > (hey might as well have ALL the newbie factors right? I mean if you are that STUPID, you might as well completely fulfill your role as a newbie idiot and recommend it for a rooftop too, right?
                    > I mean let's make ALL the newbie mistakes combined right? The only typical newbie idiot feature they missed was vertical axis, but I'll bet they were tempted...
                    >
                    > Guess what happened?
                    > Honeywell is a LAUGHINGSTOCK.
                    > NOBODY is using this hunk of garbage that
                    > a) weighs hundreds of pounds versus say 30 lbs for a competing, superior unit)
                    > b) costs way too much for the output
                    > Guess what they eliminated?
                    > The cloth blades - they decided to use real blades - the cloth ones didn't work out - gee ya think?
                    > Can we just be a bit blunt here?
                    > If anyone wants to do wind energy, get a book on it and look this stuff up.
                    > NO you don't want to use cloth blades, M'Kay?
                    > NO there is NO advantage to more than 3 blades, M'Kay? And nobody needs to keep asking that over and over every year or every decade - it was worked out LONG AGO.
                    >
                    > Why do you see rotors with too many blades? Because of cogging - people make a turbine, realize it has too much cogging to start in light winds, so they add blades to get it spinning. Startup torque. Then they imagine it "needs" or "uses" these extra blades in normal operation.
                    > NO they don't "use" the extra blades. What do the extra blades do? They cause drag - they are just along for the ride. Like if you added two more wheels to your car - 4 is all you want!
                    > So rather than treat these questions like they are brand new, why not get up to speed on the art by cracking open a book on turbine design?
                    > Why act like simple questions with simple answers are some impenetrable mystery?
                    >
                    > The problem with this group, to me, is this:
                    > Imagine a group purporting to be studying advanced mathematics. But the people in the group are asking questions like "I was trying to add a column of numbers and two digits added up to more than 9 and I didn't know what to do with the extra digit!", and someone had to explain how to "carry the remainder" (or however we said it in second grade) and you don't even know how to do simple addition using a pencil, yet you talk about advanced mathematical theory.
                    > This sounds like an exaggeration, but it's really an understatement: witness one member whom I will not mention who promotes ALL the disproven newbie ideas combined, and tries to rationalize it by citing buzzwords from advanced quantum physics. You can't make this stuff up!
                    >
                    > One cannot meaningfully discuss an art without at least a limited introductory background to that art.
                    >
                    > Why did the "smart" people at Honeywell make this mistake? They just made all the typical idiot newbie mistakes because their PhD's assumed they were SO SMART they didn't need to read the beginning textbook on the actual subject, and the bean-counters and executive decision-makers believed them. Result? Not.
                    > :)
                    > Doug Selsam
                    >
                    > --- In AirborneWindEnergy@yahoogroups.com, Pierre BENHAIEM wrote:
                    > >
                    > >
                    > > Doug, Thanks for indications.Concerning lift use your analysis joins DaveS' analysis about multi blades.But blades from Barberwind look more as lifted-based."The farm pumper is marginally a drag machine - a matter of opinion to some extent I think, and I am really not sure of the efficiency but they never work out well for generating electricity and of course many have tried."- Among other things in good conditions Tip Speed Ratio of farm pumper is only 1,too low for working by the axis a 1500 rpm conventional generator without a big gearbox.But with Rim Driven it can be different. "5 blades is two blades too many".- It is possible Barberwind and other firms use more blades for their RDWT for a structural reason,blades being also like spokes,being set on cross cables,but I am not sure of it.Another thing is that a too high Tip Speed would be a problem for wheel transmission and also for aerodynamic efficiency (losses by Rim),but I am aslo not sure of it.Profils of blades should be different with a rim (I put a ring (section 2 cm) arround a propeller (diameter 50 cm):alone the propeller turns fast,but with ring it does not turn;perhaps the tip speed should be larger,but I am not sure of it.
                    > > "Maybe drag could work for some kind of AWE since swept area is unlimited".I look again what author writes it and see the author is not DaveS but Doug! Note:the potential Pr.Crackpot could be the scientists which make calculations,in sense I supposed rightly or wrongly to be yours. PierreB> Message du 12/10/12 05:27
                    > > > De : "Doug"
                    > > > A : AirborneWindEnergy@yahoogroups.com
                    > > > Copie à :
                    > > > Objet : [AWES] Re: Rim Driven Wind Turbine (RDWT),drag-based and lift-based blades
                    > > >
                    > > > >
                    > > >
                    > > > --- In AirborneWindEnergy@yahoogroups.com, "Pierre Benhaiem" wrote: > A question for Doug,
                    > > > > Project TTU � Keuka Energy
                    > > > > claims its RDWT> with 16 drag-based blades gives a very high value of efficiency with> wind speed = 10 m/s.Diameter being 7.62 m,swept area is 45 m�
                    > > > *****Some might call that a drag machine because it has so many blades (high rotor solidity) but I think it still uses lift. You have to be careful believing such power output statistics. They may take one moment when it got a big gust and extrapolate. They never talk about the bad news. It's easy to get a turbine without overspeed protection to look like a rock star for a while, making ridiculously high amounts of power in big gusts, til eventually it burns out. These promotional statistics and probably way overestimated of the data was cherry-picked from a set that had in totality reflected lower performance - just a guess - "when it sounds too good..."
                    > > >
                    > > > University
                    > > > > of New Mexico .The resulting
                    > > > > value seems very high:52% (Betz limit being 59%),so high as value of
                    > > > > lift-based blades, comprising that of Barber Wind
                    > > > > (another RDWT with lift-based five blades).
                    > > > *******OK great Barber wind -5 blades is two blades too many - of course they are going to conquer the world.
                    > > >
                    > > > > Do you think such a high value is possible for drag-based blades?
                    > > > *****Not really. A good windmill gets a Cp of like 30% if you are lucky. And drag windmills usually do less.
                    > > > The farm pumper is marginally a drag machine - a matter of opinion to some extent I think, and I am really not sure of the efficiency but they never work out well for generating electricity and of course many have tried.
                    > > > Maybe drag could work for some kind of AWE since swept area is unlimited. In general though you want speed to generate electricity - nothing like fast blades to spin a generator and it is still never as fast as you would like and you need a special low speed generator even using lift - drag gets far worse.*********
                    > > >
                    > > > > For my knowledge the higher value for drag-based blades concerns
                    > > > > multiblade American pumping (about 30%).
                    > > > >
                    > > > > I do not think you like these sorts of designs and calculations from
                    > > > > another Pr.Crackpot,but your answer can be useful, above all if the
                    > > > > given value of these drag-based blades is too high and looks really
                    > > > > impossible
                    > > > ************Profethor Crackpot!?!?!?#%$*&$(%_%+#Y#)(*+@
                    > > > >
                    > > > > Pierre B
                    > > > >
                    > > > > Airborne Seaborne Wind Energy System (another
                    > > > > RDWT),yet another this time completely Airborne Flygen RDWT being that
                    > > > > described on Dr. Beaujean' paper.
                    > > > >
                    > > >
                    > > >
                    > >
                    >
                    >

                  • dave santos
                    Doug, You never did explain the impressive independent ratings the HW Trubine somehow earned. I recently asked Coy Harris of the Americam Windpower Museum
                    Message 10 of 26 , Oct 12, 2012
                      Doug,

                      You never did explain the impressive independent ratings the HW Trubine somehow earned.

                      I recently asked Coy Harris of the Americam Windpower Museum about Honeywell's turbine, since they had one installed a couple of years ago. He said it has performed very well for them; they were so pleased, they were upgrading the install electrics. He monitors a busy wind farm of every sort of turbine side-by-side, beyond even NREL in diversity-

                      Coy Harris as Executive Director has supervised all of this construction as well as the continued development of the museum’s collection of rare mills. On August 28, 2001, the museum’s 100th windmill was erected and new monies were secured with plans calling for an additional 100 windmills on the grounds over the next several years. 

                      Please lay the basis for your minority Conventional Wind opinions in better technical terms, with less spouting,

                      daveS
                    • dave santos
                      Pierre, Whoever mistakenly called these turbines (RDWT and Aeromotor style) drag-based ignored how formal aerodynamics defines lift and drag.
                      Message 11 of 26 , Oct 12, 2012
                        Pierre,

                        Whoever mistakenly called these turbines (RDWT and Aeromotor style) "drag-based" ignored how formal aerodynamics defines lift and drag.

                        The StatoEolien is truly drag-based (savonius) and seems to represent the worst possible aerodynamic thinking. One way to spot the problem is to divide wattage into the capital cost for installed energy unit cost- One always finds a very poor result for savonius. This cluster idea just makes it worse. This looks like the poorest design i have ever seen. Doug probably agrees

                        Savonius power is sapped by its return side moving upwind at near 2x. Savonius is also worst in power-to-weight, so its worst for flying high.

                        As AWE expert pioneers, we should not lose much time with known conventional turbine dead-ends,

                        daveS

                        PS Rim-drive is a sound power transmission idea- All cars use (reverse) rim-drive for traction.
                      • Joe Faust
                        The 7.62 m diameter RDWT at the Lubbock site contains 16 blades. The turbine has a metallic casing around the edge which has space for a drive rope to rest.
                        Message 12 of 26 , Oct 12, 2012
                          "The 7.62 m diameter RDWT at the Lubbock site contains
                          16 blades. The turbine has a metallic casing around the edge
                          which has space for a drive rope to rest. This drive rope is
                          threaded around the entire circumference of the turbine and
                          then around two direct drive variable high speed generators, the
                          master and the slave. Each generator contains a pulley with
                          five grooves resulting in the drive rope being wrapped around
                          each generator five times"
                          From the document you linked, Pierre:
                          http://districts.asme.org/districtF/ectc/I_2-1-12_Corrected_ECTC_2011_JOURNAL_VOL._10_-_Final_Part_1_-_Cover-Paper_06.pdf

                          [[[??: AWEified: fan-belt method to ground-stationed generator]]]
                        • Pierre BENHAIEM
                          Honeywell s turbine,as well as turbines from Keuka or BarberWind,is a rim driven turbine,but its generator is settled within the rotor and stator,a little like
                          Message 13 of 26 , Oct 12, 2012


                            Honeywell's turbine,as well as turbines from Keuka or BarberWind,is a rim driven turbine,but its generator is settled within the rotor and stator,a little like for flygen Beaujean's scheme.In the other hand generators from Keuka's or BarberWind are independant from the rotor which is a wheel not having a stator and being able to be lighter.

                             

                            PierreB


                             

                            > Message du 12/10/12 18:26
                            > De : "dave santos"
                            > A : "AirborneWindEnergy@yahoogroups.com"
                            > Copie à :
                            > Objet : [AWES] Coy Harris about "Honeywell's laughingstock" (confirms third-party rated performance)
                            >
                            >  

                            >

                            Doug,

                            >
                            You never did explain the impressive independent ratings the HW Trubine somehow earned.

                            >
                            I recently asked Coy Harris of the Americam Windpower Museum about Honeywell's turbine, since they had one installed a couple of years ago. He said it has performed very well for them; they were so pleased, they were upgrading the install electrics. He monitors a busy wind farm of every sort of turbine side-by-side, beyond even NREL in diversity-

                            >
                            Coy Harris as Executive Director has supervised all of this construction as well as the continued development of the museum’s collection of rare mills. On August 28, 2001, the museum’s 100th windmill was erected and new monies were secured with plans calling for an additional 100 windmills on the grounds over the next several years. 

                            >
                            Please lay the basis for your minority Conventional Wind opinions in better technical terms, with less spouting,

                            >
                            daveS
                          • Pierre BENHAIEM
                            DaveS, The paper CAPS 2010 Report: Celebrating Ten Years of Research precises in page 61 ...(RDWT) is a new concept in drag-based wind turbines... . So
                            Message 14 of 26 , Oct 12, 2012

                              DaveS,

                               

                              The paper CAPS 2010 Report: Celebrating Ten Years of Research precises in page 61 "...(RDWT) is a new concept in drag-based wind turbines...".

                               

                              So paper's definition is at least different,mentioning a drag-based HAWT _ in spite of lift component Doug and yourself mention.Is it because a confusion between the shape of the whole rotor and the shape (here as drag-based) of each blade?

                              For Airborne Seaborne Wind Energy System  this point is important since to obtain a lift from autogiro use Tips Speed Ratio must be high enough without inducing too much aerodynamic loss.So few (3 or 4) lift-based blades are expected.

                               

                              PierreB  



                              > Message du 12/10/12 19:09
                              > De : "dave santos"
                              > A : "AirborneWindEnergy@yahoogroups.com"
                              > Copie à :
                              > Objet : Re: [AWES] Rim Driven Wind Turbine (RDWT),drag-based and lift-based blades
                              >
                              >  

                              > Pierre,
                              >
                              > Whoever mistakenly called these turbines (RDWT and Aeromotor style) "drag-based" ignored how formal aerodynamics defines lift and drag.
                              >
                              > The StatoEolien is truly drag-based (savonius) and seems to represent the worst possible aerodynamic thinking. One way to spot the problem is to divide wattage into the capital cost for installed energy unit cost- One always finds a very poor result for savonius. This cluster idea just makes it worse. This looks like the poorest design i have ever seen. Doug probably agrees
                              >
                              > Savonius power is sapped by its return side moving upwind at near 2x. Savonius is also worst in power-to-weight, so its worst for flying high.
                              >
                              > As AWE expert pioneers, we should not lose much time with known conventional turbine dead-ends,
                              >
                              > daveS
                              >
                              > PS Rim-drive is a sound power transmission idea- All cars use (reverse) rim-drive for traction.
                              >

                            • Doug
                              Yes it is just another Savonius, weighing thousands of pounds to equal the output of a regular small turbine weighing perhaps 70 lbs. It uses about 20 times
                              Message 15 of 26 , Oct 12, 2012
                                Yes it is just another Savonius, weighing thousands of pounds to equal the output of a regular small turbine weighing perhaps 70 lbs. It uses about 20 times the material needed. Even their modest power estimates may be overestimates. Anyone can put renderings on the web and make claims regarding the renderings.

                                --- In AirborneWindEnergy@yahoogroups.com, Pierre BENHAIEM <pierre.benhaiem@...> wrote:> Can his design
                                http://www.gual-industrie.com/
                                improve the record in Proof-of-Crackpotness? PierreB
                                >
                                >
                                >
                              • Doug
                                Hmmm, sounds to me like they re still working out the details if they need to upgrade the electronics . They ve gotten rid of a lot of the features they
                                Message 16 of 26 , Oct 12, 2012
                                  Hmmm, sounds to me like they're still working out the details if they need to "upgrade the electronics". They've gotten rid of a lot of the features they originally said made it so great, like the cloth blades on bicycle spokes, so it's more like a regular turbine now, just using 7 times the required material. At a 6-foot diameter I seriously doubt if it makes 1500 Watts. A 6-foot diameter turbine is a 500-Watt turbine, not a 1500-Watt turbine. It weighs about 7 times too much for a 6-foot diameter turbine, and probably costs 7 times too much. I'd like to see it survive one of my ultra-punishing test sites that tear turbines to shreds. I'd give it less than one hour to total destruction. Why do turbines like this win awards? because magazines are always looking for a story, and if PhD "experts" get things this wrong, why would you expect journalists to second-guess them. Usually if an owner buys a turbine they are happy if it puts out any power at all, doesn't make too much noise, and doesn't break or burn out. See if it can pay for itself, and see if it can survive ridiculously strong winds that it will probably have to at some point.

                                  --- In AirborneWindEnergy@yahoogroups.com, dave santos <santos137@...> wrote:
                                  >
                                  > Doug,
                                  >
                                  > You never did explain the impressive independent ratings the HW Trubine somehow earned.
                                  >
                                  > I recently asked Coy Harris of the Americam Windpower Museum about Honeywell's turbine, since they had one installed a couple of years ago. He said it has performed very well for them; they were so pleased, they were upgrading the install electrics. He monitors a busy wind farm of every sort of turbine side-by-side, beyond even NREL in diversity-
                                  >
                                  > Coy Harris as Executive Director has supervised all of this construction as well as the continued development of the museum’s collection of rare mills. On August 28, 2001, the museum’s 100th windmill was erected and new monies were secured with plans calling for an additional 100 windmills on the grounds over the next several years. 
                                  >
                                  > Please lay the basis for your minority Conventional Wind opinions in better technical terms, with less spouting,
                                  >
                                  > daveS
                                  >
                                • Doug
                                  The rule of thumb is if your TSR is less than 1, it s a drag machine and if your TSR is more than one, it s a lift machine. If the TSR is exactly one, people
                                  Message 17 of 26 , Oct 12, 2012
                                    The rule of thumb is if your TSR is less than 1, it's a drag machine and if your TSR is more than one, it's a lift machine. If the TSR is exactly one, people will endlessly argue about whether it is a lift machine or a drag machine or a transsexual.

                                    --- In AirborneWindEnergy@yahoogroups.com, Pierre BENHAIEM <pierre.benhaiem@...> wrote:
                                    >
                                    >
                                    > DaveS, The paper CAPS 2010 Report: Celebrating Ten Years of Research precises in page 61 "...(RDWT) is a new concept in drag-based wind turbines...". So paper's definition is at least different,mentioning a drag-based HAWT _ in spite of lift component Doug and yourself mention.Is it because a confusion between the shape of the whole rotor and the shape (here as drag-based) of each blade?For Airborne Seaborne Wind Energy System this point is important since to obtain a lift from autogiro use Tips Speed Ratio must be high enough without inducing too much aerodynamic loss.So few (3 or 4) lift-based blades are expected. PierreB
                                    >
                                    >
                                    >
                                    > > Message du 12/10/12 19:09
                                    > > De : "dave santos"
                                    > > A : "AirborneWindEnergy@yahoogroups.com"
                                    > > Copie à :
                                    > > Objet : Re: [AWES] Rim Driven Wind Turbine (RDWT),drag-based and lift-based blades
                                    > >
                                    > > > Pierre,
                                    > >
                                    > > Whoever mistakenly called these turbines (RDWT and Aeromotor style) "drag-based" ignored how formal aerodynamics defines lift and drag.
                                    > >
                                    > > The StatoEolien is truly drag-based (savonius) and seems to represent the worst possible aerodynamic thinking. One way to spot the problem is to divide wattage into the capital cost for installed energy unit cost- One always finds a very poor result for savonius. This cluster idea just makes it worse. This looks like the poorest design i have ever seen. Doug probably agrees
                                    > >
                                    > > Savonius power is sapped by its return side moving upwind at near 2x. Savonius is also worst in power-to-weight, so its worst for flying high.
                                    > >
                                    > > As AWE expert pioneers, we should not lose much time with known conventional turbine dead-ends,
                                    > >
                                    > > daveS
                                    > >
                                    > > PS Rim-drive is a sound power transmission idea- All cars use (reverse) rim-drive for traction.
                                    > >
                                    >
                                  • dave santos
                                    Doug, The electrical upgrade was not the Honeywell product, but the farm grid side. You also managed to comepletly tune-out Coy s expert opinion in your hope
                                    Message 18 of 26 , Oct 12, 2012
                                      Doug,

                                      The electrical upgrade was not the Honeywell product, but the farm grid side.

                                      You also managed to comepletly tune-out Coy's expert opinion in your hope of knocking the Honeywell. Coy clearly has far more experience with turbines that you do (and he is more optimistic about AWE). He has installed and maintained everything from big GEs to an old "Dutch" poldermill.

                                      Don't forget your diode blew on Gipe, as if this sort of part failure is really how to judge a bad turbine,

                                      daveS

                                    • dave santos
                                      Doug wrote- The rule of thumb is if your TSR is less than 1, it s a drag machine and if your TSR is more than one, it s a lift machine. This is a misleading
                                      Message 19 of 26 , Oct 12, 2012
                                        Doug wrote- "The rule of thumb is if your TSR is less than 1, it's a drag machine and if your TSR is more than one, it's a lift machine. "

                                        This is a misleading folk notion of aerodynamics, of how Lift and Drag really are defined-

                                        Wikipedia-

                                        Lift is the component of aerodynamic force that is perpendicular to the oncoming flow direction.[1] It contrasts with the drag force, which is the component of the surface force parallel to the flow direction.

                                        http://en.wikipedia.org/wiki/Lift_(force)


                                        HAWT and Darrieus are lift-based*. Savonious is drag-based.

                                        * "-based" defined as the principle-of-operation


                                      • Doug
                                        Dave S. Why make yourself look endlessly silly? Consumer Reports:
                                        Message 20 of 26 , Oct 13, 2012
                                          Dave S. Why make yourself look endlessly silly? Consumer Reports:

                                          http://news.consumerreports.org/home/2012/08/results-of-consumer-reports-wind-turbine-tests.html

                                          Why does the Honeywell turbines not still use cloth blades on bicycle spokes? Why did they ever? How much does it cost? What about the excess weight? Does it really put out 1500 Watts?

                                          You don't know the answer to any of those questions, just like you don't know antything about wind energy, period.

                                          Honeywell STARTS with LIES:
                                          1) They compare their turbine to "turbines with a gearbox". Only the uninformed imagine there is a competing 6-foot diameter turbine with a gearbox - there are NONE.
                                          2) They claim to start producing electricity in a 2 mph wind or whatever - I watch turbines and anemometers for hours every day - the wind can't even power up an inverter til you have 5 or 6 mph, even if your turbine was 100% efficient!.

                                          Dave S., I took 2 seconds to google "cost of a honeywell wind turbine" and the first article I clicked on was Consumer Reports".
                                          Consumer Reports found the turbine put out 4 kWH in 15 Months versus about 1500 kWh promised for the site. That is ONE QUARTER OF ONE PERCENT of the claimed results from this turbine. You might as well admit it produces essentially NOTHING. I think most experts just say whatever it takes to get rid of you quickly - "sure it works great"...

                                          Consumer Reports states that their Honeywell turbine would take SEVERAL MILLENIA to pay for itself, yet it has a predicted 20-year lifetime. I can show you a decent competing turbine for about $500 versus $11,000 for this hunk-o-junk.

                                          http://news.consumerreports.org/home/2012/08/results-of-consumer-reports-wind-turbine-tests.html

                                          Here's a cut-and-paste for those online without internet access (huh?)
                                          Energy
                                          Recouping cost of wind turbine may take more than a lifetime
                                          Aug 6, 2012 12:00 PM

                                          Wind power has been the fastest growing source of new electric power, according to the U.S. Energy Information Administration. But if you're considering a wind turbine to supplement your home's power, consider our experience with one product, the Honeywell WT6500 Wind Turbine, a cautionary tale.

                                          Among the few wind turbines that can be mounted on a roof, the WT6500 is similar to traditional wind turbines: Any unused energy it generates can be sent or sold to a utility for credit off your power bill. But it's quieter than traditional turbines, and according to the manufacturer WindTronics, starts generating power at lower wind speeds. The company claims the unit starts spinning from winds of a mere 0.5 mphâ€"with electricity generated from only 3 mph. Traditional gearbox wind turbines, said the company, require at least 7.5-mph winds to start generating power.

                                          A tool on Windtronics' website had calculated we'd get 1,155 kWh per year at the 12-mph average it predicted for our area of Yonkers, New York. And the authorized installer, during his initial visit, didn't say the roof of our headquarters might generate any less, but that rating is at a height of 164 feet, not the 33 feet WindTronics requires for rooftop installations.

                                          In the 15 months since the turbine was installed, though, it has delivered less than 4 kWhâ€"enough only to power a 12,000 btu window air conditioner for one afternoon. A company representative in charge of installations worldwide recently visited our offices and confirmed that our test model was correctly installed. What's more, he told us that while the WT6500 should start generating power at about 3 mph, the initial juice goes just to power the system's inverter, which must be running before it supplies any AC power elsewhere. The true wind speed needed to start producing AC while the inverter is on is 6 mph, not far from the 7.5 mph needed by a traditional gearbox wind turbine.

                                          The Honeywell costs $11,000 installed, comes with a five-year warranty and has a 20-year expected product life. But having a thorough site analysis by a manufacturer-authorized installer, backed by your own research on websites such as the National Renewable Energy Laboratory, is vital.

                                          At the rate the WT6500 is delivering power at our test site, it would take several millennia for the product to pay for itself in savingsâ€"not the 56 years it would take even with the 1,155 kWh quote we received.

                                          â€"Ed Perratore


                                          --- In AirborneWindEnergy@yahoogroups.com, dave santos <santos137@...> wrote:
                                          >
                                          > Doug,
                                          >
                                          > The electrical upgrade was not the Honeywell product, but the farm grid side.
                                          >
                                          > You also managed to comepletly tune-out Coy's expert opinion in your hope of knocking the Honeywell. Coy clearly has far more experience with turbines that you do (and he is more optimistic about AWE). He has installed and maintained everything from big GEs to an old "Dutch" poldermill.
                                          >
                                          > Don't forget your diode blew on Gipe, as if this sort of part failure is really how to judge a bad turbine,
                                          >
                                          > daveS
                                          >
                                        • Doug
                                          Dave: I GAVE YOU the RULE OF THUMB. PERIOD. You are an uninformed NEWBIE who knows nothing, PERIOD.
                                          Message 21 of 26 , Oct 13, 2012
                                            Dave:
                                            I GAVE YOU the RULE OF THUMB. PERIOD. You are an uninformed NEWBIE who knows nothing, PERIOD.

                                            --- In AirborneWindEnergy@yahoogroups.com, dave santos <santos137@...> wrote:
                                            >
                                            > Doug wrote- "The rule of thumb is if your TSR is less than 1, it's a drag machine and if your TSR is more than one, it's a lift machine. "
                                            >
                                            > This is a misleading folk notion of aerodynamics, of how Lift and Drag really are defined-
                                            >
                                            > Wikipedia-
                                            >
                                            > Lift�is the�component of aerodynamic force that is�perpendicular�to the�oncoming�flow direction.[1]�It contrasts with the�drag�force, which is the component of the surface force�parallel�to the flow direction.
                                            >
                                            > http://en.wikipedia.org/wiki/Lift_(force)
                                            >
                                            >
                                            >
                                            > HAWT and Darrieus are lift-based*. Savonious is drag-based.
                                            >
                                            >
                                            > * "-based" defined as the principle-of-operation
                                            >
                                          • dave santos
                                            Doug, Thanks for the opinion of Senior Editor Ed Perratore to add to that of Wind Power Expert Coy Harris. Coy never opined to me about the economics of the
                                            Message 22 of 26 , Oct 13, 2012
                                              Doug,

                                              Thanks for the opinion of Senior Editor Ed Perratore to add to that of Wind Power Expert Coy Harris. Coy never opined to me about the economics of the turbine, and Ed did not seem technically able to troubleshoot the anomalous output. Coy may have had a better install in a better wind location. Buildings can have serious dead spots in their wind field. There is also the independent rating

                                              I am still collecting information here. Why must you call me names for reporting Coy's opinion? We still need to explain how these two reports can be so divergent. I have not yet rendered my final judgement on this turbine, but hope it will be a model of excellence for you to aspire to,

                                              daveS
                                            • Doug
                                              Dave: You don t need to render a final judgement on this turbine, since you know nothing of wind energy and your opinion reflects complete ignorance. You
                                              Message 23 of 26 , Oct 14, 2012
                                                Dave:
                                                You don't need to render a final judgement on this turbine, since you know nothing of wind energy and your opinion reflects complete ignorance. You already have given your opinion, and there is no doubt about it: You know everything, I know nothing, everything I say is wrong, and every crappy joke of a turbine is great.

                                                When I said Professor Crackpot is like a wheelbarrow at a Formula-1 race I was not exaggerating: Consumer Reports agrees: half of one percent of the performance is a similar ratio to 200 mph vs 1 mph. You think what I say is hype - you have no idea.

                                                I called Coy in Lubbock, Texas yesterday. He told me the real story:
                                                The Honeywell turbine experienced a 50-60 mph wind soon after being installed, which immediately burned out its "controller".
                                                The Honeywell turbine system is not operational until they can replace this critical component. What do you think is gonna happen next time they get 50-60 mph winds?

                                                Like I have said, overspeed protection is not the main thing, it's the only thing. Why? Otherwise you will have a turbine that is not operational, which can therefore produce no power. We figured out long ago that you are better off with a turbine that produces a tenth of the power if it survives. In the case of Honeywell, it produces less than 1% of the advertised energy, AND it cannot survive even the first real storm.

                                                I asked Coy how much power it had made. He told me he had no information on power at all. They were just getting their collection of wind turbines all set up, and had no way to measure output yet.

                                                Coy related that their site has the same setup as two of my test sites: 48-Volt battery systems with Xantrex grid-tie inverters. He's planning on putting about 4 turbines through the same inverter. "Funny," I told him, "we are also just about to start trying to put more than one turbine through the same exact system".

                                                I've been a fan of this wind museum in Lubbock, Texas since I first saw it on the web several years ago, noting they had a side-by-side dual-rotor farm water-pumper windmill...

                                                Thanks for the intro.
                                                Just for the record, I have a SuperTwin(TM) mounted at 14 feet height on my van in the backyard that produced 4 kWh every afternoon using a couple of 2x4's as blades. So $5 of lumber produces as much energy in an afternoon as the Honeywell produced in a year and 3 months. Yes I'm sure having a bit of wind helps...

                                                I once took a 6-bladed Hornet wind turbine (5-foot diam, 20 lbs, $500) and carefully took a power curve, measuring 50 Watts at 20 mph. I replaced the six (6) factory blades with a single wooden 2-blade straight-thru rotor (a 5-foot 1x4 from Home Depot) and measured 100 Watts at 20 mph - I got twice the power just by mounting decent blades, and far fewer of them!

                                                I guess I could have tried cloth blades too, right?
                                                K gotta go.
                                                I hope I have shown that everything you have said abou everything I say being wrong is simply wrong.

                                                Keep up the fight for ignorance!


                                                --- In AirborneWindEnergy@yahoogroups.com, dave santos <santos137@...> wrote:
                                                >
                                                > Doug,
                                                >
                                                > Thanks for the opinion of Senior Editor Ed Perratore to add to that of Wind Power Expert Coy Harris. Coy never opined to me about the economics of the turbine, and Ed did not seem technically able to troubleshoot the anomalous output. Coy may have had a better install in a better wind location. Buildings can have serious dead spots in their wind field. There is also the independent rating
                                                >
                                                > I am still collecting information here. Why must you call me names for reporting Coy's opinion? We still need to explain how these two reports can be so divergent. I have not yet rendered my final judgement on this turbine, but hope it will be a model of excellence for you to aspire to,
                                                >
                                                > daveS
                                                >
                                              • dave santos
                                                Doug, When i askd Coy about the Honeyell he seemed to like it. He strangely did not blame the HW controller at that time, but we did not spend a lot a time
                                                Message 24 of 26 , Oct 14, 2012
                                                  Doug,

                                                  When i askd Coy about the Honeyell he seemed to like it. He strangely did not blame the HW controller at that time, but we did not spend a lot a time going into it.

                                                  Thanks for digging deeper than your two-minute search for Consumer Reports. We now know both Honeywell and your turbines are subject to similar failure, but your emotional reaction is different depending on whose failure is considered.

                                                  The wind tunnel error you mention is well known. That is why i am still wanting to run down that lead; to see what really went down with that test. This is not a "fight for ignorance", but a patient gathering of facts.

                                                  Its still an open question if there is a performance intersection of ducted turbines and modern turbofan engines. We could reach high speeds with our turbines by sweeping them in fast wind, and the duct is favored operationally due to lower snagging risk, even though cost and weight seem to go the other way.

                                                  Why don't you donate a Selsam machine to the mueseum?

                                                  daveS

                                                • Doug
                                                  Hey Dave S. Wrong wrong wrong. I have turbines at the most punishing sites possible, where big-name heavy-duty turbines lasted only months. You have stated
                                                  Message 25 of 26 , Oct 15, 2012
                                                    Hey Dave S.
                                                    Wrong wrong wrong. I have turbines at the most punishing sites possible, where big-name heavy-duty turbines lasted only months.
                                                    You have stated unequivocally that the Honeywell Turbine is a good turbine. It is YOU who are wrong. You who make reckless statements based on knowing nothing of wind energy and being unwilling to learn.
                                                    Only idiots defend the Honeywell turbine. The real wind energy groups have been making fun of it for years. So, have at it, my good professor!

                                                    It is one more example of you knowing absolutely nothing about wind energy. There's only one reason you try to say the Honeywell turbine is good - because I tried to warn you it is bad, and you think it's your duty to refute every fact introduced to this group in your continued fight for ignorance.

                                                    It is only an ignorant person who could compare the Honeywell at hundreds of pounds, over ten thousand of dollars, with high-level corporate backing, that has been shown to be useless in the only two cases we've seen so far:
                                                    1) not enough wind
                                                    2) too much wind
                                                    Notice the pattern there? The turbine is still "perfect" even though it is shown to always fail, it is now "the wind's fault!"
                                                    Too much wind, too little wind - maybe all it needs is a "Little REd Riding Hood site where the wind is always "juuuuust right" Ya think? Then maybe it could make the 500 Watts or so a turbie of its size can be expected to produce. But of course the owner has still paid twenty times too much for a 500-Watt turbine.
                                                    You can't make this stuff up!

                                                    And you want to cite a corporate-sponsored, in-production turbine, with millions of dollars in PhD "work" behind it, millions of dollars in development and tooling, as "the same" as my prototype that, using two 2x4's from Home Deopt as blades, lasted a year in a windfarm, and which simply blew a $1 diode that was not even part of the turbine at all, just a randomly-chosen and disposable automotive rectifier that could be replaced anytime for ten bucks and a drive to Autozone.

                                                    Dave S., real wind energy systems can be forgiven for needing a small, easily replaced electronic part after a year of torture, but if you remember, it was just a prototype anyway.

                                                    You are comparing a machine that ran for a year, producing great power the whole time, in all wind regimes, to a machine that IMMEDIATELY shows it makes no power in light winds and cannot handle strong winds.

                                                    The Honeywell turbine is not alone - ALL professor Crackpot turbines are like that. You just don't know about it because all this is new to you, and you are seeing it for the fist time. Obviously you are naturally drawn to each losing idea, rather than seeing what works and going with it.

                                                    I need to stop wasting my time telling you anything since your fight for ignorance proves you do not like facts.

                                                    --- In AirborneWindEnergy@yahoogroups.com, dave santos <santos137@...> wrote:
                                                    >
                                                    > Doug,
                                                    >
                                                    > When i askd Coy about the Honeyell he seemed to like it. He strangely did not blame the HW controller at that time, but we did not spend a lot a time going into it.
                                                    >
                                                    > Thanks for digging deeper than your two-minute search for Consumer Reports. We now know both Honeywell and your turbines are subject to similar failure, but your emotional reaction is different depending on whose failure is considered.
                                                    >
                                                    > The wind tunnel error you mention is well known. That is why i am still wanting to run down that lead; to see what really went down with that test. This is not a "fight for ignorance", but a patient gathering of facts.
                                                    >
                                                    > Its still an open question if there is a performance intersection of ducted turbines and modern turbofan engines. We could reach high speeds with our turbines by sweeping them in fast wind, and the duct is favored operationally due to lower snagging risk, even though cost and weight seem to go the other way.
                                                    >
                                                    > Why don't you donate a Selsam machine to the mueseum?
                                                    >
                                                    > daveS
                                                    >
                                                  • dave santos
                                                    In summary, my personal finding is the Honeywell turbine is over-claimed, over-engineered, and vastly over-priced. Its very unsuited for average sites where
                                                    Message 26 of 26 , Oct 15, 2012

                                                      In summary, my personal finding is the Honeywell turbine is over-claimed, over-engineered, and vastly over-priced. Its very unsuited for average sites where the most-probable-windspeed is well below its "ideal" wind.

                                                      Its low power-to-weight makes it unattractive for AWE, but the shrouded rotor format suggests a possible future direction for AWTs that operate in smooth strong high-altitude winds with caged rotors that prevent snagging on kite lines.

                                                      It no real mystery why Coy Harris, the top conventional windpower master of our circle, can still like a turbine like this, and share the fun with those like him. The Honeywell is like the infamous Edsel automobile, a sort of interesting odd-duck appreciated as a collectable. Doug and Paul Gipe are no less correct to point out the defects as they relate to the small windpower consumer. 

                                                      Doug is badly mistaken on one point- It seems no one besides promoters ever "stated unequivocally that the Honeywell Turbine is a good turbine."




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