Thanks eric, Yes you are confirming my thinking. I knew about the waterturbine site and they look like best bet so far. Those Nautilus look really good. I can probably build the required structure you suggest. Working on top is WAY easier than down the hole! On channelling I had a couple of ideas. One is to recess a slanted panel through which I could install one or more of those LH1000 tube style generators. THe slant would focus low flow through the lowest of the set and if I had more than one and flow was high, the slanted pan would fill and divert excess flow to second one. I'd put a final overflow for excess at highest end.
--- Eric Youngren <[EMAIL PROTECTED]> wrote: > > Steinaman, > > Interesting site. Thanks for posting the pictures. I don't have any > direct experience with this type of low-head, high-flow microhydro, but I > have a few thoughts... > > First, you might as well forget about a pelton turbine, you don't have the > head for it and even if you had a bit more, the runner would need to be huge > to handle the flow you have. What you need is a reaction turbine, like a > Kaplan or propeller type. Check out www.waterturbine.com for some > "micro" scale commercially available reaction turbines. > > Could you build a small building on top of the "weir tower" to house the > turbine and generator, with a draft tube extending down 10'? You'd have > to build up the weir on 3 sides (or knock out one side a bit) to channel all > the flow into the intake. I'm not sure how you'd design the intake and > screening arrangement , but perhaps Bob at Hydroscreen could help.: > www.hydroscreen.com > > The water diversion idea you mention might turn out to be an easier way to > go if you can channel the flow into a penstock that drops steeply over the > edge of the bank or dam. I think the reaction turbine could be mounted > either above or below the drop. > > Good luck, and keep us posted! > > Eric > > > > > ----- Original Message ----- > From: "steinaman" [EMAIL PROTECTED] > To: <[email protected]> > Sent: Monday, April 04, 2005 9:08 AM > Subject: [microhydro] Site evaluation - advice wanted > > > > > > > > > > Site evaluation - help wanted > > (a folder by that name has been created for reference) > > Given this site, whats easist design to install and maintain? > > > > An Engineering problem: > > (I had posted this previously but got minimal response. > > I hope I simplified the description enough for more feedback.) > > I have a good site, but not enough knowledge/experience to use it. > > My concerns are less to do with the electronics than with the site > > 'engineering'. > > How best to select the proper turbine, place it and channel flow to > > it. > > How to do it in a low impact, low cost and best ROI way with long life > > and low maintenance. > > Once that's more clear to me I can focus on the wiring issues. > > This would serve a rural/suburban home about 100 yards away which > > currently uses about 1000 KWH per month. Would prefer to 'offset or > > feed the grid' at first and consider batteries at a later date. > > > > DESCRIPTION: (in Northern Ct., USA) > > A one acre manmade (1960s) pond, 17 ft at deepest, fed by two > > streams, > > which outlets through a vertical concrete wier on the dam side. > > The dam is earthen, the wier is built like a fireplace/chimney > > structure standing about 14 feet into pond from the dam base, > > which is about 12' deep water at that point. (pics in folder) > > Water flows in at the top through trash rack and exits from the base > > thorugh a 24" concrete pipe running out of the dam base. > > > > The 30"x24" trash grate at the top has a perimieter of 108". > > All flow goes through that , nearly year round. > > Flow over this varies from zero(some, not all Augusts) to 3" most > > winters. > > I have used wier calculations and the 108" pereimeter to find the > > flow varies from 0 to 1700 GPM. > > Lets say it averages 600 over a year. > > There is a 10' drop inside the concrete structure. > > This is the maximum head I can achieve on my property. > > > > Here are my primary questions: > > - is my math right? I am not sure the standard 'wier' calculations I > > see, all illustrated as a board in a stream, apply here. > > I.e. do I calculate flow potential correctly? > > (see folder's excel file 'Hydrocalc.xls') > > In that file I calculate between 600 to 3200 watts/sec (gross) > > at low (300 GPM) to maximum(1700 GPM) flows. > > > > - which turbine type and placement gains most from this setup? > > Optimum solutions avoid draining the pond for installation, > > but that's not out of the question. > > -do I construct a flow diversion to concentrate woter flow over > > a pelton turbine installed in bottom of wier to gain the most > > available head, or > > -do I mount a flow through turbine at top, or > > -do I adapt the outlet pipe to take power from the concentrated > > flow there. > > -do I drill a pipe through base of wier to feed nozzle(s) against > > a pelton wheel installed down there with the force applied by > > 1 acre of pond surface 10 ' above. > > -do I increase pressure and gained energy output by channeling > > the 108" of flow through a pipe or sluice to the turbine? > > or does channeling only help me attain the maximum potential of > > the calculations? > > > > Besides obvious differences in installation logistics are there > > major tradeoffs in achieved output? > > > > I think those are the most important issues for me to begin with. > > thanks to all in advance. > > Feel free to send directed reply ([EMAIL PROTECTED]) if you dont wish > > to do broadcast posting. > > > > > > > > > > > > > > > > > > > > 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 > > > > > > > > > > > > > > > > > > > > > > Email: [EMAIL PROTECTED] phone: 860-693-1673 (Home office) __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com ------------------------ 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/
