1)About maintainig the AC voltage and frequency, yes you have to make sure they are maintained. Changes in the frequency affects the stability of the whole system. The frequency can be stabilised by good load management. This means that if the load is greater than what you can supply you have to shed some loads and if the load is smaller than what your power station can supply you can turn of some turbines if you have a number of them. this can be a good time for maintaining the turbines ie greasing serving worn out parts, checking safety devices. 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. This might make you go for the lowest flow rate in the creek so as to have a consistent flow rate to the turbines. This might be abit of wastage. The other alternative is to adjust the flow rate for particular seasons so that the amount of power produced varies with the time of the year. Lower power in the drier seasons and more power in the lower seasons. I hope this can be of some help 2) Yes it matters if the power is not consistent due to lower flow rates in a particular week. the dc produced by the inverter wil also be varying 3) Yes the power loses are there but 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.
danieldykim <[EMAIL PROTECTED]> wrote: Hello, I'm kind of new to this microhydro subject, but I've been trying to learn, after finding out that our newly acquired property has a year- round stream... any help and info on this topic would be greatly appreciated.. For our stream, the approx head is 120ft, flow is probably 70-80GPM (what we can get out of the creek). With that configuration, we're probably looking at a 500w system... but the problem is this: The creek is about 800ft away from the residence. That's too far for any DC current to travel on a reasonably-sized wire. So some people have pointed me toward AC hydrogenerators.. To have the AC come up from the creek, and then convert it to DC (using the inverter/charger) at the residence to charge the batteries. (we definitely want to go with the batteries instead of using the power directly, since this is a weekend-high-usage situation) Now the questions (if any of you could even answer just one or two, that would be very helpful in getting me up to speed with this topic): 1) I heard that AC hydrogenerators need to have some way of making consistent AC voltage / frequency.. So does that mean I need to hit the "lowest common denominator" by tuning the generator to produce 60Hz at the lowest flow time of the season? Would that result in wasting power? 2) How does the inverter handle the AC current from the hydrogenerator, if it's not very consistent? (like if there's lower flow one week). Does it matter? 3) Is it better & simpler to just get a DC generator (which is cheaper), convert it to AC at the creek, and then move it up to the residence, and then convert it back to DC? Is there much power loss during those conversions? 4) I'm thinking of getting a 4-nozzle pelton wheel system, but I also heard of some other systems like "stream engine" which works better at low flow situations. Would my stream (120 ft head, 60 gpm flow) work well with the pelton wheel? Thank you very much for reading. Any help would be greatly appreciated. --Daniel 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 SponsorADVERTISEMENT document.write(''); --------------------------------- 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 the Yahoo! Terms of Service. --------------------------------- Do you Yahoo!? Yahoo! Search presents - Jib Jab's 'Second Term' [Non-text portions of this message have been removed] ------------------------ 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/
