> you wrote: > > Hoagy, > > Looked at, > > "Wind Energy Systems" > http://www.eece.ksu.edu/~gjohnson/ > > Liked it as a basic text book, but it seems a bit old on newer development. > Well worth to read. > > Hakan
Thanks Hakan. The basics are what I need to understand. He does talk about the Darrieus VAWT quiet allot it seems. I was reading Chapter One - Introduction and he went through some historical highlights. One of them was about the Savonius Vertical Axis Wind Turbine regarding its Cp (power Coefficient) or efficiency. He writes in section 5 Innovative Wind Turbines page 1-17 -- "A chart of efficiency of five different turbine types is shown in Fig. 8. The efficiency or power coefficient varies with the ratio of blade tip speed to wind speed, with the peak value being the number quoted for a comparison of turbines. This will be discussed in more detail in Chapter 4. It may be noticed that the peak efficiencies of the two bladed propeller, the Darrieus, and the Savonius are all above 30%, while the American Multiblade and the Dutch windmills peak at about 15%. These efficiencies indicate that the American Multiblade is not competitive for generating electricity, even though it is almost ideally suited and very competitive for pumping water. The efficiency curves for the Savonius and the American Multiblade have been known for a long time [6, 10]. Unfortunately, the labels on the two curves were accidentally interchanged in some key publication in recent years, with the result that many authors have used an erroneous set of curves in their writing. This historical accident will probably take years to correct." It appears the DVAWT & the SVAWT or some variation could provide suitable options for the VW-turbine idea at least in terms of efficiency. > > Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Biofuels list archives: http://archive.nnytech.net/index.php?list=biofuel Please do NOT send Unsubscribe messages to the list address. To unsubscribe, send an email to: [EMAIL PROTECTED] Yahoo! Groups Links To visit your group on the web, go to: http://groups.yahoo.com/group/biofuel/ To unsubscribe from this group, send an email to: [EMAIL PROTECTED] Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
