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new turbine design

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  • Michael Dewolf
    What about this turbine design. (I ve attached it) It s not really a turbine. But I thought that it would be useful in areas where more power is needed.
    Message 1 of 17 , Mar 1, 2001
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      What about this turbine design. (I've attached it)

      It's not really a turbine. But I thought that it would be useful in areas
      where more power is needed. Since it transfers the energy more directly, it
      has a higher efficiency.

      Maybe useful for high head, very low flow flows.

      What do you guys (and gals) think?

      Michael


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    • Lancie1@aol.com
      Michael Dewolf s new design would use very little kinetic energy, therefore wouldn t it be slow compared to a cross-flow or Pelton design? My first thoughts
      Message 2 of 17 , Mar 1, 2001
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        Michael Dewolf's new design would use very little kinetic energy,
        therefore wouldn't it be slow compared to a cross-flow or Pelton
        design? My first thoughts are that the two additional sets of
        bearings would create additional maintenance, especially the lower
        wheel. Aso, it might be difficult to obtain the materials for the
        flexible belt or chain to make the loop around the wheels. I would
        think that overall there would not be significant advantages over a
        traditional water wheel.
      • m_dewolf@engineer.com
        When I originally devised the turbine design, I was under the understanding that existing turbines weren t very efficient. I read somewhere that home water
        Message 3 of 17 , Mar 1, 2001
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          When I originally 'devised' the turbine design, I was under the
          understanding that existing turbines weren't very efficient. I read
          somewhere that home water power projects are about 18 percent
          efficient compared to the theoretical amount of energy. (mass times
          hight times g).

          I was just recently looking at another site that said that most
          turbines are 60 - 85 percent efficient.

          Any explaination?

          Michael
        • m_dewolf@engineer.com
          Thinking out loud here.. 60 -85 percent might be the efficiency measured by before and after water conditions. (ie. enthalpy) 18 % would be the overall
          Message 4 of 17 , Mar 1, 2001
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            Thinking out loud here..

            60 -85 percent might be the efficiency measured by before and after
            water conditions. (ie. enthalpy)

            18 % would be the overall efficiency
          • m_dewolf@engineer.com
            One other thing, the 60 - 80 percent would be the before and after water conditions like enthalpy, which includes presure and temperature, AND VELOCITY (not a
            Message 5 of 17 , Mar 1, 2001
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              One other thing,

              the 60 - 80 percent would be the before and after water conditions
              like enthalpy, which includes presure and temperature, AND VELOCITY
              (not a part of enthalpy)
            • hugh piggott
              I am not sure what enthalpy is actually but an impulse turbine such as a pelton or turgo should be 60-80% efficient. It removes the kinetic energy from the
              Message 6 of 17 , Mar 2, 2001
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                I am not sure what enthalpy is actually but an impulse turbine such
                as a pelton or turgo should be 60-80% efficient. It removes the
                kinetic energy from the water by stopping it. There are losses due
                to splashing and to windage.

                >
                >>
                >>You can access this file at the URL
                >>
                >>http://groups.yahoo.com/group/microhydro/files/new%20turbine.jpg

                that's if you can remember your password! heigh ho.
                --
                Hugh

                Scoraig, Scotland
                http://www.scoraigwind.co.uk
              • dirk vansintjan
                An overshot waterwheel has an efficiency of about 80 % and almost no problems with leaves and branches. See website of hydrowatt http://www.hydrowatt.de Dirk
                Message 7 of 17 , Mar 2, 2001
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                  An overshot waterwheel has an efficiency of about 80 % and almost no
                  problems with leaves and branches.
                  See website of hydrowatt
                  http://www.hydrowatt.de

                  Dirk Vansintjan

                  -----Original Message-----
                  From: m_dewolf@... <m_dewolf@...>
                  To: microhydro@yahoogroups.com <microhydro@yahoogroups.com>
                  Date: vrijdag 2 maart 2001 4:17
                  Subject: [microhydro] Re: new turbine design


                  >One other thing,
                  >
                  >the 60 - 80 percent would be the before and after water conditions
                  >like enthalpy, which includes presure and temperature, AND VELOCITY
                  >(not a part of enthalpy)
                  >
                  >
                  >NOTE: The advertisements in this email are added by Yahoogroups who
                  provides us with free email group services. The microhydro-group does not
                  endorse products or support the advertisements in any way.
                  >
                  >More information on micro hydropower at
                  http://geocities.com/wim_klunne/hydro
                  >
                  >To unsubscribe: send empty message to microhydro-unsubscribe@...
                  >
                  >Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
                  >
                  >
                • Denis Vincent
                  Small Pelton, as tested in our lab, allows a mechanical efficiency of 90%. A reasonable efficiency for the genrator or the alternator is 92 to 94 %. So is the
                  Message 8 of 17 , Mar 2, 2001
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                    Small Pelton, as tested in our lab, allows a mechanical efficiency of 90%. A
                    reasonable efficiency for the genrator or the alternator is 92 to 94 %. So
                    is the overall efficiency between 83% and 85%. A better overall efficiency
                    could be obtained with small kaplan and small francis (if developped in a
                    lab).

                    In order to be sure that we speak of the same thing, the overall efficiency
                    is the electrical power divided by the hydraulic power.

                    Regards,

                    Vincent DENIS

                    P.S. : I agree with Dirk v.S., an overshot waterwheel has a mechanical
                    efficiency of 80 % if well designed. So is the overall efficiency of about
                    74 %.

                    MHyLab - 1354 Montcherand - Switzerland
                    Tél : + 41 24 442 86 20 Fax : + 41 24 441 36 54
                    e-mail : denisv@...
                    http://www.ambios.ch/mhylab
                    http://www.smallhydro.ch
                  • m_dewolf@engineer.com
                    ... efficiency ... How do you define hydraulic power? Cheers, Michael
                    Message 9 of 17 , Mar 2, 2001
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                      Denis Vincent <denisv@m...> wrote:
                      > In order to be sure that we speak of the same thing, the overall
                      efficiency
                      > is the electrical power divided by the hydraulic power.

                      How do you define hydraulic power?

                      Cheers,

                      Michael
                    • Denis Vincent
                      Hydraulic power = Ro x Q x g x H = Specific weight x Flow x acceleration due to gravity x net head. If the penstock (in case we have a penstock) is well
                      Message 10 of 17 , Mar 2, 2001
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                        Hydraulic power = Ro x Q x g x H = Specific weight x Flow x acceleration due
                        to gravity x net head.

                        If the penstock (in case we have a penstock) is well designed, the net head
                        at maximum flow must not be lower than 0.9 Gross Head.

                        Best regards,

                        Vincent.

                        MHyLab - 1354 Montcherand - Switzerland
                        Tél : + 41 24 442 86 20 Fax : + 41 24 441 36 54
                        e-mail : denisv@...
                        http://www.ambios.ch/mhylab
                        http://www.smallhydro.ch



                        > -----Message d'origine-----
                        > De : m_dewolf@... [mailto:m_dewolf@...]
                        > Envoyé : vendredi, 2. mars 2001 13:40
                        > À : microhydro@yahoogroups.com
                        > Objet : [microhydro] Re: Overall efficiency
                        >
                        >
                        > Denis Vincent <denisv@m...> wrote:
                        > > In order to be sure that we speak of the same thing, the overall
                        > efficiency
                        > > is the electrical power divided by the hydraulic power.
                        >
                        > How do you define hydraulic power?
                        >
                        > Cheers,
                        >
                        > Michael
                        >
                        >
                        >
                        >
                        >
                        >
                        >
                        >
                        >
                        >
                        > NOTE: The advertisements in this email are added by
                        > Yahoogroups who provides us with free email group services.
                        > The microhydro-group does not endorse products or support the
                        > advertisements in any way.
                        >
                        > More information on micro hydropower at
                        > http://geocities.com/wim_klunne/hydro
                        >
                        > To unsubscribe: send empty message to
                        > microhydro-unsubscribe@...
                        >
                        > Your use of Yahoo! Groups is subject to
                        > http://docs.yahoo.com/info/terms/
                        >
                        >
                      • evansengineering@cs.com
                        Claiming 90% efficiency for a small pelton plant is unrealistic unless you are excluding jet losses, windage and bearing losses, which is misleading. As for
                        Message 11 of 17 , Mar 2, 2001
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                          Claiming 90% efficiency for a small pelton plant is unrealistic unless you
                          are excluding jet losses, windage and bearing losses, which is misleading. As
                          for generator efficiency being 92% to 94% you are working on larger three
                          phase units in the 50 plus kW size. Most small generators are in the range 85
                          to 88%. It makes me cross when non-manufacturers claim efficiencies that are
                          not realistic or economic to achieve with small plants. Polishing a runner to
                          get the last few % is worth it on a 100MW plant but not on a 5kW plant.
                          Rupert Evans
                        • Denis Vincent
                          If you don t trust me, please come to see us and you will have to admit that small peltons can have a mechanical efficiency of 89 to 90%. It s not a legend,
                          Message 12 of 17 , Mar 3, 2001
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                            If you don't trust me, please come to see us and you will have to admit that
                            small peltons can have a mechanical efficiency of 89 to 90%. It's not a
                            legend, just facts !!

                            This efficiency is measured as the efficiency at the coupling between the
                            turbine and the generator.

                            For small Peltons, you are right; it is unrealistic to polish the runner !!!
                            That's why you have to manufacture runner s with mounted buckets, made by
                            CNC machining.

                            Never forget that the efficiency IS NOT a pure unrealistic engineering
                            dream, but the witness of a good mechanical and hydraulic behaviour, what
                            means a reliable turbine.

                            Don't forget that it is not more expensive to build a bad turbine than a
                            good one !!

                            Once again, if you don't trust that it is possible to make small turbines
                            with such efficiency, please come to Switzerland and France and I will show
                            you units with 10 kW and top efficiency. If they where built, there was
                            certainly an economical reason !!

                            Small power does not mean poor design and inefficient material, as you may
                            think !!

                            I know that this mail will certainly not convince you that we are right, but
                            we cannot accept to be treated as liars.

                            We are not manufacturers, but we are small turbine designers and our
                            developments are made in a lab. Our clients are turbines manufacturers ! So
                            we think that we can say something on the efficiency and turbine design !

                            Sorry to send this e-mail to the whole group and to make you loose your
                            time, but it seems important to me to say that :

                            I don't agree with Mr.Evans mail,
                            Our Lab is open to anybody wishing to verify that we are right when claiming
                            90% efficiency for small Peltons.

                            Best regards to the whole group,

                            Vincent Denis
                            Hydraulic design engineer and Head of the laboratory.

                            P.S. 1 : MHyLab = Mini Hydraulic Laboratory !
                            P.S. 2 : We are now working on Kaplan turbine with the same range of
                            efficiency and for power between 7 kW and 800 kW.

                            MHyLab - 1354 Montcherand - Switzerland
                            Tél : + 41 24 442 86 20 Fax : + 41 24 441 36 54
                            e-mail : denisv@...
                            http://www.ambios.ch/mhylab
                            http://www.smallhydro.ch



                            > -----Message d'origine-----
                            > De : evansengineering@... [mailto:evansengineering@...]
                            > Envoyé : vendredi, 2. mars 2001 17:27
                            > À : microhydro@yahoogroups.com
                            > Objet : Re: [microhydro] Re: new turbine design
                            >
                            >
                            > Claiming 90% efficiency for a small pelton plant is
                            > unrealistic unless you
                            > are excluding jet losses, windage and bearing losses, which
                            > is misleading. As
                            > for generator efficiency being 92% to 94% you are working on
                            > larger three
                            > phase units in the 50 plus kW size. Most small generators are
                            > in the range 85
                            > to 88%. It makes me cross when non-manufacturers claim
                            > efficiencies that are
                            > not realistic or economic to achieve with small plants.
                            > Polishing a runner to
                            > get the last few % is worth it on a 100MW plant but not on a
                            > 5kW plant.
                            > Rupert Evans
                            >
                            > NOTE: The advertisements in this email are added by
                            > Yahoogroups who provides us with free email group services.
                            > The microhydro-group does not endorse products or support the
                            > advertisements in any way.
                            >
                            > More information on micro hydropower at
                            > http://geocities.com/wim_klunne/hydro
                            >
                            > To unsubscribe: send empty message to
                            > microhydro-unsubscribe@...
                            >
                            > Your use of Yahoo! Groups is subject to
                            > http://docs.yahoo.com/info/terms/
                            >
                            >
                          • evansengineering@cs.com
                            In reply to your e-mail. I agree with much of what you say but : 1. I have seen several of the largest and most prestigious turbine manufacturers in the world
                            Message 13 of 17 , Mar 3, 2001
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                              In reply to your e-mail. I agree with much of what you say but :
                              1. I have seen several of the largest and most prestigious turbine
                              manufacturers in the world make claims that are just not true.
                              2. You say that you measure the output power at the shaft coupling. Where do
                              you measure input head and flow ?
                              3. If you really are getting 90% overall turbine efficiency at these small
                              powers, you are the best in the business.
                              4. I would hardly be so rude as to call you a liar, I thought this was a
                              discussion group and if you claim 90% I don't think it is unreasonable for me
                              to ask how you measure it and also what you charge for a 10 kW turbine. If
                              your performance and your price are realistic, you win!
                              Regards Rupert Evans
                            • duyspvn
                              At last after all, efficiency of this new turbine? How to design this turbine? can anyone show for me? Thank ... admit that ... between the ... runner !!! ...
                              Message 14 of 17 , May 20 6:02 AM
                              • 0 Attachment
                                At last after all, efficiency of this new turbine?
                                How to design this turbine? can anyone show for me?
                                Thank


                                --- In microhydro@yahoogroups.com, Denis Vincent <denisv@...> wrote:
                                >
                                > If you don't trust me, please come to see us and you will have to
                                admit that
                                > small peltons can have a mechanical efficiency of 89 to 90%. It's not a
                                > legend, just facts !!
                                >
                                > This efficiency is measured as the efficiency at the coupling
                                between the
                                > turbine and the generator.
                                >
                                > For small Peltons, you are right; it is unrealistic to polish the
                                runner !!!
                                > That's why you have to manufacture runner s with mounted buckets,
                                made by
                                > CNC machining.
                                >
                                > Never forget that the efficiency IS NOT a pure unrealistic engineering
                                > dream, but the witness of a good mechanical and hydraulic behaviour,
                                what
                                > means a reliable turbine.
                                >
                                > Don't forget that it is not more expensive to build a bad turbine than a
                                > good one !!
                                >
                                > Once again, if you don't trust that it is possible to make small
                                turbines
                                > with such efficiency, please come to Switzerland and France and I
                                will show
                                > you units with 10 kW and top efficiency. If they where built, there was
                                > certainly an economical reason !!
                                >
                                > Small power does not mean poor design and inefficient material, as
                                you may
                                > think !!
                                >
                                > I know that this mail will certainly not convince you that we are
                                right, but
                                > we cannot accept to be treated as liars.
                                >
                                > We are not manufacturers, but we are small turbine designers and our
                                > developments are made in a lab. Our clients are turbines
                                manufacturers ! So
                                > we think that we can say something on the efficiency and turbine
                                design !
                                >
                                > Sorry to send this e-mail to the whole group and to make you loose your
                                > time, but it seems important to me to say that :
                                >
                                > I don't agree with Mr.Evans mail,
                                > Our Lab is open to anybody wishing to verify that we are right when
                                claiming
                                > 90% efficiency for small Peltons.
                                >
                                > Best regards to the whole group,
                                >
                                > Vincent Denis
                                > Hydraulic design engineer and Head of the laboratory.
                                >
                                > P.S. 1 : MHyLab = Mini Hydraulic Laboratory !
                                > P.S. 2 : We are now working on Kaplan turbine with the same range of
                                > efficiency and for power between 7 kW and 800 kW.
                                >
                                > MHyLab - 1354 Montcherand - Switzerland
                                > Tél : + 41 24 442 86 20 Fax : + 41 24 441 36 54
                                > e-mail : denisv@...
                                > http://www.ambios.ch/mhylab
                                > http://www.smallhydro.ch
                                >
                                >
                                >
                                > > -----Message d'origine-----
                                > > De : evansengineering@... [mailto:evansengineering@...]
                                > > Envoyé : vendredi, 2. mars 2001 17:27
                                > > À : microhydro@yahoogroups.com
                                > > Objet : Re: [microhydro] Re: new turbine design
                                > >
                                > >
                                > > Claiming 90% efficiency for a small pelton plant is
                                > > unrealistic unless you
                                > > are excluding jet losses, windage and bearing losses, which
                                > > is misleading. As
                                > > for generator efficiency being 92% to 94% you are working on
                                > > larger three
                                > > phase units in the 50 plus kW size. Most small generators are
                                > > in the range 85
                                > > to 88%. It makes me cross when non-manufacturers claim
                                > > efficiencies that are
                                > > not realistic or economic to achieve with small plants.
                                > > Polishing a runner to
                                > > get the last few % is worth it on a 100MW plant but not on a
                                > > 5kW plant.
                                > > Rupert Evans
                                > >
                                > > NOTE: The advertisements in this email are added by
                                > > Yahoogroups who provides us with free email group services.
                                > > The microhydro-group does not endorse products or support the
                                > > advertisements in any way.
                                > >
                                > > More information on micro hydropower at
                                > > http://geocities.com/wim_klunne/hydro
                                > >
                                > > To unsubscribe: send empty message to
                                > > microhydro-unsubscribe@...
                                > >
                                > > Your use of Yahoo! Groups is subject to
                                > > http://docs.yahoo.com/info/terms/
                                > >
                                > >
                                >
                              • Carlos Bonifetti
                                Vincent, Rupert and all, Both points of view are very important and interesting. The Vincent one is credible because I know the effort made in Switzeland por
                                Message 15 of 17 , May 22 9:06 AM
                                • 0 Attachment
                                  Vincent, Rupert and all,

                                  Both points of view are very important and interesting.
                                  The Vincent one is credible because I know the effort made in Switzeland por design and construction of very good an efficient turbines in range from micro to big machines, as I can see in september 1992 at the Microhydro Cours at SKAT. Many times it's the same labour and cost involved in a bad construction machine than a good one. Even, sometimes a bad construction can be more costly than a good one.
                                  The Rupert comment for less efficiency must be held as micro Pelton turbine construction with less technological aid, as CNC or other precision foundry methods, not easy and economical available in 3rd. world countries. That is the most general fact than are finded outside developed countries.
                                  The overall efficiency is governed at last by the size and generator efficiency as Rupert had said.


                                  Regards,
                                  Carlos Bonifetti
                                  -------------------------------------------------------------------------------------------------



                                  ----- Original Message -----
                                  From: duyspvn
                                  To: microhydro@yahoogroups.com
                                  Sent: Sunday, May 20, 2007 9:02 AM
                                  Subject: [microhydro] Re: new turbine design



                                  At last after all, efficiency of this new turbine?
                                  How to design this turbine? can anyone show for me?
                                  Thank

                                  --- In microhydro@yahoogroups.com, Denis Vincent <denisv@...> wrote:
                                  >
                                  > If you don't trust me, please come to see us and you will have to
                                  admit that
                                  > small peltons can have a mechanical efficiency of 89 to 90%. It's not a
                                  > legend, just facts !!
                                  >
                                  > This efficiency is measured as the efficiency at the coupling
                                  between the
                                  > turbine and the generator.
                                  >
                                  > For small Peltons, you are right; it is unrealistic to polish the
                                  runner !!!
                                  > That's why you have to manufacture runner s with mounted buckets,
                                  made by
                                  > CNC machining.
                                  >
                                  > Never forget that the efficiency IS NOT a pure unrealistic engineering
                                  > dream, but the witness of a good mechanical and hydraulic behaviour,
                                  what
                                  > means a reliable turbine.
                                  >
                                  > Don't forget that it is not more expensive to build a bad turbine than a
                                  > good one !!
                                  >
                                  > Once again, if you don't trust that it is possible to make small
                                  turbines
                                  > with such efficiency, please come to Switzerland and France and I
                                  will show
                                  > you units with 10 kW and top efficiency. If they where built, there was
                                  > certainly an economical reason !!
                                  >
                                  > Small power does not mean poor design and inefficient material, as
                                  you may
                                  > think !!
                                  >
                                  > I know that this mail will certainly not convince you that we are
                                  right, but
                                  > we cannot accept to be treated as liars.
                                  >
                                  > We are not manufacturers, but we are small turbine designers and our
                                  > developments are made in a lab. Our clients are turbines
                                  manufacturers ! So
                                  > we think that we can say something on the efficiency and turbine
                                  design !
                                  >
                                  > Sorry to send this e-mail to the whole group and to make you loose your
                                  > time, but it seems important to me to say that :
                                  >
                                  > I don't agree with Mr.Evans mail,
                                  > Our Lab is open to anybody wishing to verify that we are right when
                                  claiming
                                  > 90% efficiency for small Peltons.
                                  >
                                  > Best regards to the whole group,
                                  >
                                  > Vincent Denis
                                  > Hydraulic design engineer and Head of the laboratory.
                                  >
                                  > P.S. 1 : MHyLab = Mini Hydraulic Laboratory !
                                  > P.S. 2 : We are now working on Kaplan turbine with the same range of
                                  > efficiency and for power between 7 kW and 800 kW.
                                  >
                                  > MHyLab - 1354 Montcherand - Switzerland
                                  > Tél : + 41 24 442 86 20 Fax : + 41 24 441 36 54
                                  > e-mail : denisv@...
                                  > http://www.ambios.ch/mhylab
                                  > http://www.smallhydro.ch
                                  >
                                  >
                                  >
                                  > > -----Message d'origine-----
                                  > > De : evansengineering@... [mailto:evansengineering@...]
                                  > > Envoyé : vendredi, 2. mars 2001 17:27
                                  > > À : microhydro@yahoogroups.com
                                  > > Objet : Re: [microhydro] Re: new turbine design
                                  > >
                                  > >
                                  > > Claiming 90% efficiency for a small pelton plant is
                                  > > unrealistic unless you
                                  > > are excluding jet losses, windage and bearing losses, which
                                  > > is misleading. As
                                  > > for generator efficiency being 92% to 94% you are working on
                                  > > larger three
                                  > > phase units in the 50 plus kW size. Most small generators are
                                  > > in the range 85
                                  > > to 88%. It makes me cross when non-manufacturers claim
                                  > > efficiencies that are
                                  > > not realistic or economic to achieve with small plants.
                                  > > Polishing a runner to
                                  > > get the last few % is worth it on a 100MW plant but not on a
                                  > > 5kW plant.
                                  > > Rupert Evans
                                  > >
                                  > > NOTE: The advertisements in this email are added by
                                  > > Yahoogroups who provides us with free email group services.
                                  > > The microhydro-group does not endorse products or support the
                                  > > advertisements in any way.
                                  > >
                                  > > More information on micro hydropower at
                                  > > http://geocities.com/wim_klunne/hydro
                                  > >
                                  > > To unsubscribe: send empty message to
                                  > > microhydro-unsubscribe@...
                                  > >
                                  > > Your use of Yahoo! Groups is subject to
                                  > > http://docs.yahoo.com/info/terms/
                                  > >
                                  > >
                                  >





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                                  [Non-text portions of this message have been removed]
                                • duyspvn
                                  Dear all, This turbine is one of parts in my thesis. But now, I cannot find any thing about estimation of output and efficiency. Can you show me any
                                  Message 16 of 17 , May 23 12:14 AM
                                  • 0 Attachment
                                    Dear all,
                                    This turbine is one of parts in my thesis.
                                    But now, I cannot find any thing about estimation of output and
                                    efficiency.
                                    Can you show me any information about this new turbine?
                                    Thank you very much,
                                    Nguyen Duy



                                    --- In microhydro@yahoogroups.com, Carlos Bonifetti <cbonifetti@...>
                                    wrote:
                                    >
                                    > Vincent, Rupert and all,
                                    >
                                    > Both points of view are very important and interesting.
                                    > The Vincent one is credible because I know the effort made in
                                    Switzeland por design and construction of very good an efficient
                                    turbines in range from micro to big machines, as I can see in
                                    september 1992 at the Microhydro Cours at SKAT. Many times it's the
                                    same labour and cost involved in a bad construction machine than a
                                    good one. Even, sometimes a bad construction can be more costly than a
                                    good one.
                                    > The Rupert comment for less efficiency must be held as micro Pelton
                                    turbine construction with less technological aid, as CNC or other
                                    precision foundry methods, not easy and economical available in 3rd.
                                    world countries. That is the most general fact than are finded outside
                                    developed countries.
                                    > The overall efficiency is governed at last by the size and generator
                                    efficiency as Rupert had said.
                                    >
                                    >
                                    > Regards,
                                    > Carlos Bonifetti
                                    >
                                    -------------------------------------------------------------------------------------------------
                                    >
                                    >
                                    >
                                    > ----- Original Message -----
                                    > From: duyspvn
                                    > To: microhydro@yahoogroups.com
                                    > Sent: Sunday, May 20, 2007 9:02 AM
                                    > Subject: [microhydro] Re: new turbine design
                                    >
                                    >
                                    >
                                    > At last after all, efficiency of this new turbine?
                                    > How to design this turbine? can anyone show for me?
                                    > Thank
                                    >
                                    > --- In microhydro@yahoogroups.com, Denis Vincent <denisv@> wrote:
                                    > >
                                    > > If you don't trust me, please come to see us and you will have to
                                    > admit that
                                    > > small peltons can have a mechanical efficiency of 89 to 90%.
                                    It's not a
                                    > > legend, just facts !!
                                    > >
                                    > > This efficiency is measured as the efficiency at the coupling
                                    > between the
                                    > > turbine and the generator.
                                    > >
                                    > > For small Peltons, you are right; it is unrealistic to polish the
                                    > runner !!!
                                    > > That's why you have to manufacture runner s with mounted buckets,
                                    > made by
                                    > > CNC machining.
                                    > >
                                    > > Never forget that the efficiency IS NOT a pure unrealistic
                                    engineering
                                    > > dream, but the witness of a good mechanical and hydraulic behaviour,
                                    > what
                                    > > means a reliable turbine.
                                    > >
                                    > > Don't forget that it is not more expensive to build a bad
                                    turbine than a
                                    > > good one !!
                                    > >
                                    > > Once again, if you don't trust that it is possible to make small
                                    > turbines
                                    > > with such efficiency, please come to Switzerland and France and I
                                    > will show
                                    > > you units with 10 kW and top efficiency. If they where built,
                                    there was
                                    > > certainly an economical reason !!
                                    > >
                                    > > Small power does not mean poor design and inefficient material, as
                                    > you may
                                    > > think !!
                                    > >
                                    > > I know that this mail will certainly not convince you that we are
                                    > right, but
                                    > > we cannot accept to be treated as liars.
                                    > >
                                    > > We are not manufacturers, but we are small turbine designers and our
                                    > > developments are made in a lab. Our clients are turbines
                                    > manufacturers ! So
                                    > > we think that we can say something on the efficiency and turbine
                                    > design !
                                    > >
                                    > > Sorry to send this e-mail to the whole group and to make you
                                    loose your
                                    > > time, but it seems important to me to say that :
                                    > >
                                    > > I don't agree with Mr.Evans mail,
                                    > > Our Lab is open to anybody wishing to verify that we are right when
                                    > claiming
                                    > > 90% efficiency for small Peltons.
                                    > >
                                    > > Best regards to the whole group,
                                    > >
                                    > > Vincent Denis
                                    > > Hydraulic design engineer and Head of the laboratory.
                                    > >
                                    > > P.S. 1 : MHyLab = Mini Hydraulic Laboratory !
                                    > > P.S. 2 : We are now working on Kaplan turbine with the same range of
                                    > > efficiency and for power between 7 kW and 800 kW.
                                    > >
                                    > > MHyLab - 1354 Montcherand - Switzerland
                                    > > Tél : + 41 24 442 86 20 Fax : + 41 24 441 36 54
                                    > > e-mail : denisv@
                                    > > http://www.ambios.ch/mhylab
                                    > > http://www.smallhydro.ch
                                    > >
                                    > >
                                    > >
                                    > > > -----Message d'origine-----
                                    > > > De : evansengineering@ [mailto:evansengineering@]
                                    > > > Envoyé : vendredi, 2. mars 2001 17:27
                                    > > > À : microhydro@yahoogroups.com
                                    > > > Objet : Re: [microhydro] Re: new turbine design
                                    > > >
                                    > > >
                                    > > > Claiming 90% efficiency for a small pelton plant is
                                    > > > unrealistic unless you
                                    > > > are excluding jet losses, windage and bearing losses, which
                                    > > > is misleading. As
                                    > > > for generator efficiency being 92% to 94% you are working on
                                    > > > larger three
                                    > > > phase units in the 50 plus kW size. Most small generators are
                                    > > > in the range 85
                                    > > > to 88%. It makes me cross when non-manufacturers claim
                                    > > > efficiencies that are
                                    > > > not realistic or economic to achieve with small plants.
                                    > > > Polishing a runner to
                                    > > > get the last few % is worth it on a 100MW plant but not on a
                                    > > > 5kW plant.
                                    > > > Rupert Evans
                                    > > >
                                    > > > NOTE: The advertisements in this email are added by
                                    > > > Yahoogroups who provides us with free email group services.
                                    > > > The microhydro-group does not endorse products or support the
                                    > > > advertisements in any way.
                                    > > >
                                    > > > More information on micro hydropower at
                                    > > > http://geocities.com/wim_klunne/hydro
                                    > > >
                                    > > > To unsubscribe: send empty message to
                                    > > > microhydro-unsubscribe@
                                    > > >
                                    > > > Your use of Yahoo! Groups is subject to
                                    > > > http://docs.yahoo.com/info/terms/
                                    > > >
                                    > > >
                                    > >
                                    >
                                    >
                                    >
                                    >
                                    >
                                    > __________ Información de NOD32, revisión 2284 (20070522) __________
                                    >
                                    > Este mensaje ha sido analizado con NOD32 antivirus system
                                    > http://www.nod32.com
                                    >
                                    >
                                    > [Non-text portions of this message have been removed]
                                    >
                                  • ian benson
                                    As regards efficiancy figures, Once you start putting forward figures like 89-90% or 92-94% , you need to state how accurately you are measuring it -
                                    Message 17 of 17 , May 23 11:38 AM
                                    • 0 Attachment
                                      As regards efficiancy figures,
                                      Once you start putting forward figures like '89-90%' or '92-94%', you
                                      need to state how accurately you are measuring it - Getting a
                                      confidance interval around 1% in such efficiency measurements needs a
                                      quality test set-up, and that's what you have to convince people like
                                      Rupert and myself you have used to get these figures.

                                      And, again, are jet losses included in your efficiency figures? (I
                                      understand any jet with an efficiency over 0.97 is almost a
                                      miracle!).

                                      I think 90% for small peltons, including jet losses, ought to be
                                      possible - basically because theory says so. Interesting posting,
                                      thanks.
                                      Regards,
                                      Ian Benson.

                                      On 5/23/07, duyspvn <duyspar@...> wrote:
                                      > Dear all,
                                      > This turbine is one of parts in my thesis.
                                      > But now, I cannot find any thing about estimation of output and
                                      > efficiency.
                                      > Can you show me any information about this new turbine?
                                      > Thank you very much,
                                      > Nguyen Duy
                                      >
                                      >
                                      >
                                      > --- In microhydro@yahoogroups.com, Carlos Bonifetti <cbonifetti@...>
                                      > wrote:
                                      > >
                                      > > Vincent, Rupert and all,
                                      > >
                                      > > Both points of view are very important and interesting.
                                      > > The Vincent one is credible because I know the effort made in
                                      > Switzeland por design and construction of very good an efficient
                                      > turbines in range from micro to big machines, as I can see in
                                      > september 1992 at the Microhydro Cours at SKAT. Many times it's the
                                      > same labour and cost involved in a bad construction machine than a
                                      > good one. Even, sometimes a bad construction can be more costly than a
                                      > good one.
                                      > > The Rupert comment for less efficiency must be held as micro Pelton
                                      > turbine construction with less technological aid, as CNC or other
                                      > precision foundry methods, not easy and economical available in 3rd.
                                      > world countries. That is the most general fact than are finded outside
                                      > developed countries.
                                      > > The overall efficiency is governed at last by the size and generator
                                      > efficiency as Rupert had said.
                                      > >
                                      > >
                                      > > Regards,
                                      > > Carlos Bonifetti
                                      > >
                                      > -------------------------------------------------------------------------------------------------
                                      > >
                                      > >
                                      > >
                                      > > ----- Original Message -----
                                      > > From: duyspvn
                                      > > To: microhydro@yahoogroups.com
                                      > > Sent: Sunday, May 20, 2007 9:02 AM
                                      > > Subject: [microhydro] Re: new turbine design
                                      > >
                                      > >
                                      > >
                                      > > At last after all, efficiency of this new turbine?
                                      > > How to design this turbine? can anyone show for me?
                                      > > Thank
                                      > >
                                      > > --- In microhydro@yahoogroups.com, Denis Vincent <denisv@> wrote:
                                      > > >
                                      > > > If you don't trust me, please come to see us and you will have to
                                      > > admit that
                                      > > > small peltons can have a mechanical efficiency of 89 to 90%.
                                      > It's not a
                                      > > > legend, just facts !!
                                      > > >
                                      > > > This efficiency is measured as the efficiency at the coupling
                                      > > between the
                                      > > > turbine and the generator.
                                      > > >
                                      > > > For small Peltons, you are right; it is unrealistic to polish the
                                      > > runner !!!
                                      > > > That's why you have to manufacture runner s with mounted buckets,
                                      > > made by
                                      > > > CNC machining.
                                      > > >
                                      > > > Never forget that the efficiency IS NOT a pure unrealistic
                                      > engineering
                                      > > > dream, but the witness of a good mechanical and hydraulic behaviour,
                                      > > what
                                      > > > means a reliable turbine.
                                      > > >
                                      > > > Don't forget that it is not more expensive to build a bad
                                      > turbine than a
                                      > > > good one !!
                                      > > >
                                      > > > Once again, if you don't trust that it is possible to make small
                                      > > turbines
                                      > > > with such efficiency, please come to Switzerland and France and I
                                      > > will show
                                      > > > you units with 10 kW and top efficiency. If they where built,
                                      > there was
                                      > > > certainly an economical reason !!
                                      > > >
                                      > > > Small power does not mean poor design and inefficient material, as
                                      > > you may
                                      > > > think !!
                                      > > >
                                      > > > I know that this mail will certainly not convince you that we are
                                      > > right, but
                                      > > > we cannot accept to be treated as liars.
                                      > > >
                                      > > > We are not manufacturers, but we are small turbine designers and our
                                      > > > developments are made in a lab. Our clients are turbines
                                      > > manufacturers ! So
                                      > > > we think that we can say something on the efficiency and turbine
                                      > > design !
                                      > > >
                                      > > > Sorry to send this e-mail to the whole group and to make you
                                      > loose your
                                      > > > time, but it seems important to me to say that :
                                      > > >
                                      > > > I don't agree with Mr.Evans mail,
                                      > > > Our Lab is open to anybody wishing to verify that we are right when
                                      > > claiming
                                      > > > 90% efficiency for small Peltons.
                                      > > >
                                      > > > Best regards to the whole group,
                                      > > >
                                      > > > Vincent Denis
                                      > > > Hydraulic design engineer and Head of the laboratory.
                                      > > >
                                      > > > P.S. 1 : MHyLab = Mini Hydraulic Laboratory !
                                      > > > P.S. 2 : We are now working on Kaplan turbine with the same range of
                                      > > > efficiency and for power between 7 kW and 800 kW.
                                      > > >
                                      > > > MHyLab - 1354 Montcherand - Switzerland
                                      > > > Tél : + 41 24 442 86 20 Fax : + 41 24 441 36 54
                                      > > > e-mail : denisv@
                                      > > > http://www.ambios.ch/mhylab
                                      > > > http://www.smallhydro.ch
                                      > > >
                                      > > >
                                      > > >
                                      > > > > -----Message d'origine-----
                                      > > > > De : evansengineering@ [mailto:evansengineering@]
                                      > > > > Envoyé : vendredi, 2. mars 2001 17:27
                                      > > > > À : microhydro@yahoogroups.com
                                      > > > > Objet : Re: [microhydro] Re: new turbine design
                                      > > > >
                                      > > > >
                                      > > > > Claiming 90% efficiency for a small pelton plant is
                                      > > > > unrealistic unless you
                                      > > > > are excluding jet losses, windage and bearing losses, which
                                      > > > > is misleading. As
                                      > > > > for generator efficiency being 92% to 94% you are working on
                                      > > > > larger three
                                      > > > > phase units in the 50 plus kW size. Most small generators are
                                      > > > > in the range 85
                                      > > > > to 88%. It makes me cross when non-manufacturers claim
                                      > > > > efficiencies that are
                                      > > > > not realistic or economic to achieve with small plants.
                                      > > > > Polishing a runner to
                                      > > > > get the last few % is worth it on a 100MW plant but not on a
                                      > > > > 5kW plant.
                                      > > > > Rupert Evans
                                      > > > >
                                      > > > > NOTE: The advertisements in this email are added by
                                      > > > > Yahoogroups who provides us with free email group services.
                                      > > > > The microhydro-group does not endorse products or support the
                                      > > > > advertisements in any way.
                                      > > > >
                                      > > > > More information on micro hydropower at
                                      > > > > http://geocities.com/wim_klunne/hydro
                                      > > > >
                                      > > > > To unsubscribe: send empty message to
                                      > > > > microhydro-unsubscribe@
                                      > > > >
                                      > > > > Your use of Yahoo! Groups is subject to
                                      > > > > http://docs.yahoo.com/info/terms/
                                      > > > >
                                      > > > >
                                      > > >
                                      > >
                                      > >
                                      > >
                                      > >
                                      > >
                                      > > __________ Información de NOD32, revisión 2284 (20070522) __________
                                      > >
                                      > > Este mensaje ha sido analizado con NOD32 antivirus system
                                      > > http://www.nod32.com
                                      > >
                                      > >
                                      > > [Non-text portions of this message have been removed]
                                      > >
                                      >
                                      >
                                      >
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