At 5:30 AM -0800 12/2/05, mujabi mycal wrote: > Since the flow at the creek is not constant i think the flow rate >is supposed to be made constant by the sluice gates which are >supposed to automatically regulate the amount of water going to the >turbines.
You can control the flow in the turbine by the size and number of nozzles used. I have never heard of using sluice gates for this purpose. Maybe I am missing something here? Surplus water just goes over the weir and is not used. > it is better to transfer ac power because they are less losses in >transmission of ac power than of dc power. Overall i think you will >loose more power by taking dc power all the way to the residence, >convert it to dc power at the creek and transmit it to the residence >the use an inverter to change it back to dc. I have to disagree with this statement. AC is used for power transmission mainly because it is easy to transform the voltage up and down as required. Higher voltage is better for efficient transmission. But if you are feeding a rectifier with no transformer, then it is better to have the transmission after the rectifier (using DC) than before (using AC). DC current is smoother than AC. With AC the rms current is higher than the mean current, and so the loss is higher, for a given mean current into the battery. At 12:31 PM -0300 14/2/05, Carlos Bonifetti wrote: >Hello Daniel. > >Your site is good for generating with some 400 - 500 W power with a 4 nozzle >pico-Pelton or Turgo 2 jets runner. (Total efficiency is no more than 30 - >40% for picohydro.) That is interesting. 120ft head, and probably 70-80GPM, means gross power 1600-1800 watts. I would normally achieve close to 50% overall after pipe loss, turbine loss and alternator loss. I use C-2C with induction motors for AC and I use PM alternators for DC. These alternators are a little expensive compared to car alternators, but give much better efficiency and longer life. At present PM alternators from Harris or Stream Engine are very costly but it would not be hard to build them in a low tech way similar to the way I build small wind turbines, and get very high efficiency still. Magnets are getting cheaper. The high rpm makes the job easy. >If it is possible, you can put the batteries inside a small house aside a >turbine- DC generator assembly togheter the inverter and go the 800 ft down >to your house in AC current. That's another good suggestion we have not had yet on this thread. -- Hugh Scoraig Wind Electric http://www.scoraigwind.co.uk/ ------------------------ Yahoo! Groups Sponsor --------------------~--> Has someone you know been affected by illness or disease? Network for Good is THE place to support health awareness efforts! http://us.click.yahoo.com/RzSHvD/UOnJAA/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/
