> -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On > Behalf Of Alberto Monteiro > Sent: Wednesday, July 12, 2006 3:45 PM > To: Killer Bs Discussion > Subject: RE: An Inconvenient Truth > > Dan Minette wrote: > > > > You should still get great variation in power output. A 20 mph wind > > has 64x the power of a 5 mph wind, and 8x the power of a 10 mph > > wind. > > > Power = k v^3 ?
Yup. > I can't see this relation. Intuitively, I would imagine > that the RPM of the generator is proportional to the speed, > and the power to the square of the RPM, so it would be > Power = k v^2. Look at the power in the atmosphere. The power in each molecule is 1/2 mv^2. The number of molecules that flow past, the turbines goes as v. Thus, the total power goes as k v^3. This is akin to aerodynamic drag at k v^3. Yes, there are some complications with different flow regimes existing at different speed, but that's the basic physics. The power that is output from the turbine at various speeds, or even at the same speed, can be matched to the input power by varying the load. Dan M. _______________________________________________ http://www.mccmedia.com/mailman/listinfo/brin-l
