Can you help my husband???? Alternative power

Discussion in 'Designing, building, making and powering your life' started by living simple, Jul 20, 2008.

  1. living simple

    living simple Junior Member

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    Hi all,

    Is there anyone out that who is a guru on converting large volumes of water with low pressure into power? i have an irrigation pump and was hoping to modify it to reverse flow to achieve some torque backwards out the input shaft?????? I have an Ajax irrigation pump with the dimensions 150 input, 80 output with a 400 diameter impeller.

    Can i call you to chat about this??? Any help would be much appreciated!

    Cheers
    Matt (and Lyn)
     
  2. dgriffith

    dgriffith Junior Member

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    Re: Can you help my husband???? Alternative power

    Well, I ain't no guru, but I'll stick my nose in anyway :lol:

    You really need a decent head to get any power back out of your irrigation pump, due to the relatively small 80mm inlet, and the fact that there's only one inlet (unlike typical pelton turbines, which fire three jets towards the impellor).

    What's the pump's rated flow on a low (eg, 2m) head? As a vague estimate (depends on the impellor, really) you'll need at least half that amount of water getting back into it to get out about 1/4 of the power that usually goes into driving it. It's kind of tricky cramming all that water into it without much pressure behind it. If you can run a relatively long length of outlet pipe (biggest dia. possible) from the pump back downstream a fair ways you can get a good suction effect from the weight of the water falling there and help draw the water through.

    How much drop have you got to work with?
     
  3. living simple

    living simple Junior Member

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    Re: Can you help my husband???? Alternative power

    Hi there, thanks for that reply. A few more questions for you then!!

    I'm guessing a bit, but I think it's 30litres per second, so i reckon that's about 15 litres per second to get 4 kw - would sound about right?? or not?? :)

    We can run a fairly large pipe in both inlet and oulet for a long way, as volume of water is not a problem - just head! Are you able to recommend something else (to ustilise this water for power?) if this irrigation pump isn't ideal??

    Thanks for your help!

    Cheers
     
  4. springtide

    springtide Junior Member

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    Re: Can you help my husband???? Alternative power

    Hi, looking at your post and you really need the head pressure to get an irrigation pump to generate power - eg at 2 meters head the water would be spitting out very fast and to get some power out of it the water has to go in at a similar speed, this means pressure. For something different try platypuspower.com.au :D .
     
  5. permasculptor

    permasculptor Junior Member

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    Re: Can you help my husband???? Alternative power

    What about a shallow water wheel or a series of them.You could perhaps convert industrial air blowers or whirly vents.Just a thought.
     
  6. SueinWA

    SueinWA Junior Member

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    Re: Can you help my husband???? Alternative power

    I'm sticking my nose in this, even though I don't know anything about mechanical stuff. I am a mechanical dummy. I can work a light switch, but that's it.

    But someone, somewhere, was telling about using a hydraulic ram pump for low-head to pump water higher than the the height you started with. I think.

    Look here and see if what I think they meant and what I think you want are the same thing: https://en.wikipedia.org/wiki/Hydraulic_ram

    If it's not applicable, please just ignore my ignorance and butting in.

    Sue
     
  7. the brutus

    the brutus Junior Member

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    Re: Can you help my husband???? Alternative power

    Hi!

    if you have a large volume of water without much pressure behind it, I would recommend a old-fashioned waterwheel, or some salvaged modern equivalent. Your irrigation pump was designed to operate at high RPM, attached to a motor or engine. Low head (pressure) water is not going to be moving fast, so whatever you pass it through must be able to extract useful energy at low speed. A Francis turbine would be nice, but very dear. I like to improvise, and its cheap! The idea posted earlier about an industrial air fan, the drum type, not the prop. type, is not bad at all.

    For a generator that works on very low RPM, i would recommend a permanent magnet DC motor, and avoid alternators, as their cut in speed is very high. If you can salvage the heater-fan motor out of an old truck that runs 24V you are on the right track, as his can allow you to get 12-14 volts at less than the motors rated speed. Most of these have brushes and simple commutators so they produce DC output directly. Stepper motors can also work well, but will need a rectifier. The output of such a dodgy homebrew system is only going to be a few amps, but operating around the clock this can amount to a useful supplement to a RAPS system. And it can be made cheap and recycled.

    You are very lucky to have such a supply of water, I have only a dam and rainfall. Always wanted to build a low budget micro hydro rig.

    best of luck,

    Brett
     
  8. Michaelangelica

    Michaelangelica Junior Member

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    Re: Can you help my husband???? Alternative power

    These pumps always seemed magical energy producers to me when I read about them in Earth Garden, Grass Roots etc

    Probably not what your looking for but an idea to ponder perhaps
    https://en.wikipedia.org/wiki/Hydraulic_ram

    https://www.freepatentsonline.com/7190088.html
    https://virtual.clemson.edu/groups/irrig/Equip/ram.htm

    i see someone else has already posted this SNAP.

    Somehow there should be away of generating or saving some power using a Hydralic ram- surely?
    Where are the inventors and tinkerers? :rolleyes:
     
  9. Michaelangelica

    Michaelangelica Junior Member

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    Re: Can you help my husband???? Alternative power

    I just came accross this article which might be of interest?
    https://discovermagazine.com/2008/oct/08 ... m=charcoal
     
  10. Ojo

    Ojo Junior Member

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    Re: Can you help my husband???? Alternative power

    vortex generator
    https://blog.hasslberger.com/2007/06/wat ... _plan.html
    which generates electricity from the spin, as distinct from the fall of water. The KCT
    harnesses the energy in a vortex. Drawing from the Coriolis force it promises to supplement
    conventional hydroelectricity to produce clean green renewable energy;
    excerpt
    https://www.aph.gov.au/house/committee/i ... /sub72.pdf

    a cheap DIY ram pump
    https://www.motherearthnews.com/Do-It-Yo ... -Pump.aspx
     

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