Hydro powered generator

Discussion in 'Power Electronics' started by shezza, Aug 19, 2016.

  1. shezza

    Thread Starter Member

    Mar 19, 2014
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    Hi all,

    I recently moved into a place with a creek running through it. I am wanted to install a mini water wheel to create electricity and am open to buying something ready or possibly building it myself. The creek is pretty tiny with a not so great flow rate, so I am talking about a wheel around about 6 or so inches large. I only dabble in electronics, so I am a bit nervous about starting from scratch. Any leads would be appreciated!

    Thanks!
     
  2. BR-549

    Well-Known Member

    Sep 22, 2013
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    I have no experience. I would start with a bicycle wheel rim. I would mount small paddles of some kind, sideways, all around the rim, were the tire would normally go.

    I would mount a belt pulley, where a normal bike sprocket would go. Use a fan belt to drive another pulley on a car alternator.

    Mount a debris diverter upstream of wheel. You will have to experiment with wheel depth and pulley ratios, to see what kind of power you can get. Also different diameter wheels.

    If it looks feasible, you might consider some type of water leveling structure or device in the wheel area. Or mounted on a float, if you have room. Or the drop from a small dam or culvert (pipe) could turn the wheel.

    I'm sure there are better ideas with experience and your particular stream. Good luck.
     
    Last edited: Aug 19, 2016
  3. hp1729

    Well-Known Member

    Nov 23, 2015
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    Speed is important. Starting small? A bicycle generator puts out about 9 Volts at 660 mA or so.
    Larger? A car generator requires a few thousand RPM to put out full power.
     
  4. #12

    Expert

    Nov 30, 2010
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    Good point. 5 to 10 watts might not even begin to turn a car alternator designed for a kilowatt.
    I'm sure there is math to estimate the power available from the water flow, but it is beyond my skills.:(
    Answers to hydraulic problems might be found on a different website.

    http://www.borstengineeringconstruction.com/Undershot_Water_Wheel_Design_Calculator.html
     
  5. Alec_t

    AAC Fanatic!

    Sep 17, 2013
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    1 kg metre/sec = 9.8W. So 1kg/s of water falling 1m would potentially produce 9.8W in a 100% efficient system..
     
    #12 likes this.
  6. hp1729

    Well-Known Member

    Nov 23, 2015
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    Thanks.
     
  7. shortbus

    AAC Fanatic!

    Sep 30, 2009
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    As I pointed out in another thread recently, people are forgetting the gearing in a bicycle generator. the small knurled hub on a bike generator is being driven by the tire, at many times the speed of the tire.
     
  8. tcmtech

    Well-Known Member

    Nov 4, 2013
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    We need to know the approximate flow rate of the stream and the elevation drop you have to be able to do any degree of calculations in order to give you any workable suggestions.
     
  9. shezza

    Thread Starter Member

    Mar 19, 2014
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    Thanks for all the replies!

    The drop and flow rate is nothing exciting. On its best day, it wouldn't drive anything great, but constant power output is a higher priority than maximum gains. Being it is still technically winter, it is not at its worst state yet, so probably not the most useful time to measure.
    Ultimately though, I am really more after plans, existing generators and the sort? Building one from scratch... Sure I would like to, but projects much smaller than this wear me out mentally sadly.
     
  10. blocco a spirale

    AAC Fanatic!

    Jun 18, 2008
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    Since you're the only person here with access to the creek you need to carry out your own experiments to find out what might work. From your description, the creek is too small to provide any useful energy (except perhaps to power some LEDs) so whatever you build will have little more than novelty value. A bicycle wheel with a dynohub may get you something but at this stage the challenge is of a mechanical nature rather than electrical/ electronic.
     
    Last edited: Aug 23, 2016
  11. tcmtech

    Well-Known Member

    Nov 4, 2013
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    And that defines gallons/liters per minute and elevation drop how? o_O
     
  12. crutschow

    Expert

    Mar 14, 2008
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    The OP said "The creek is pretty tiny with a not so great flow rate" so I think it's safe to assume that the elevation drop is also small and an estimate that it can't generate much power is a reasonable one. :rolleyes:
     
  13. tcmtech

    Well-Known Member

    Nov 4, 2013
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    Around here a creek could be anywhere from less than a garden hose flow rate to several hundred GPM or more.

    It's what I have ~50 feet from the front of my house.
     
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