The PATs do require a "speed governor" or a Electronic Level Controller ( ELC) and sometimes with other names.
Some control the frequency and some control the output level and even some may do control both at different times. The PATs are quite specific with their requirements and it may be necessary to have more than one to be able to attain the maximum power harvesting available due to the seasonal variable power availability. The cost savings sometimes are low that many times is best not to use them. Unhappily, the manufacturers of pumps do not produce them as a STOCK Item -- they could produce the Pump and on the side offer the impeller for the PAT and the buyer/user to change them --but not such thing is available. Regards Nando ----- Original Message ----- From: "Activism98201" <[EMAIL PROTECTED]> To: <[email protected]> Sent: Saturday, January 22, 2005 12:57 PM Subject: RE: [microhydro] High Specific Speed Impulse Turbines? > > > Thanks for the clarification. This is more closely what I was thinking that > the information that I had read implied. As stated, I'm not very polished > at all this stuff, just learning it (no practical experience, nor no real > background in electrical systems/theory). > > So I guess why question (for subsequent clarification) would be: > > Can speed governors help rectify/level out the sensitivity problems with > these high specific speed impulse turbines? Or does/would the addition of > this extra component negate the cost savings of this PAT(?) > > Ugh, I feel that I've gotten in way over my head. I appreciate people's > patience in helping educate me on this stuff. > > > -Mark Nagel > Everett, WA > -----Original Message----- > From: H2MJD [mailto:[EMAIL PROTECTED] > Sent: Friday, January 21, 2005 8:31 AM > To: [email protected] > Subject: Re: [microhydro] High Specific Speed Impulse Turbines? > > > > Perhaps Mr. Nagel meant Electronic SPEED governor.....I've always wondered > if speed controllers could be used as power point trackers when doing a > utility interfaced system. My understanding is that some speed controllers > allow for backfeeding the grid......am i wrong? > ----- Original Message ----- > From: Max Enfield > To: [email protected] > Sent: Friday, January 21, 2005 2:07 AM > Subject: Re: [microhydro] High Specific Speed Impulse Turbines? > > > > [EMAIL PROTECTED] wrote: > > > > While trying to track down information on Pump As Turbine (PAT) I ran > across "High Specific Speed Impulse Turbines." > > > > NOTE: I'm just a novice with all this stuff, but isn't the issue that > these folks are looking to overcome addressed for PAT by using electronic > load controllers? > > > > BTW - PAT looks really great for small installations (and for > long-term viability [pumps being ubiquitous]). > > > > -Mark Nagel > > Everett, WA > > A detailed discussion of "specific speed" can be found in any textbook > on > hydro-power. Briefly, it is a number dependent on the geometry of a > turbine. > If head, rpm and output efficiency are held constant, then the higher > the flow > rate a turbine can handle, the higher will be its specific speed. So, > for > example adding more jets to a Pelton wheel will increase its specific > speed. > > It has nothing to do with electronic load governors. > > Regards, > > Max Enfield > Planetary Power > > > > [Non-text portions of this message have been removed] > > > > > > > > Does your company feature in the microhydro business directory at http://microhydropower.net/directory ? If not, please register free of charge and be exposed to the microhydro community world wide! > > 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://microhydropower.net > > To unsubscribe: send empty message to [EMAIL PROTECTED] > Yahoo! Groups Links > > > > > > > ------------------------ Yahoo! Groups Sponsor --------------------~--> In low income neighborhoods, 84% do not own computers. At Network for Good, help bridge the Digital Divide! http://us.click.yahoo.com/EA3HyD/3MnJAA/79vVAA/FGYolB/TM --------------------------------------------------------------------~-> Does your company feature in the microhydro business directory at http://microhydropower.net/directory ? If not, please register free of charge and be exposed to the microhydro community world wide! 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://microhydropower.net To unsubscribe: send empty message to [EMAIL PROTECTED] Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/microhydro/ <*> 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/
