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Potato batteries.

Discussion in 'Alternative Energy' started by Nigel Goodwin, Feb 25, 2009.

  1. Nigel Goodwin

    Nigel Goodwin Super Moderator Most Helpful Member

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    There's been various talk about using lemons and such to produce electricity (actually from the dissimilar metals).

    There's just been a kids TV show on here, and they used a potato to work a clock - as you would expect, it worked fine, due to the miniscule current requirement.

    They then wired 1700 potatoes and managed to run a small portable radio off of them - but it wasn't clear if they were just in parallel, or in series parallel to give an acceptable voltage.

    There was a multimeter there, next to the radio, but it wasn't connected :(
     
  2. duffy

    duffy New Member

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    Let's see...
    say 1 potato = 500µW, enough for an LCD clock...

    1,700 potatoes = 0.85W, enough for a small radio...

    74,568,000 potatoes = 50 hp, but if each potato weighs 3oz then it's almost seven-thousand tons of potatos...

    Nope. The potato-powered car just isn't going to work this way.
     
  3. Andy1845c

    Andy1845c Active Member

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    Damn, guess its all up to HHO to solve our energy crisis now.... not the humble potato farmer.....:D

    This thread made me smile:)
     
  4. dave

    Dave New Member

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  5. picbits

    picbits Well-Known Member

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    Who's been watching gastronaughts ? :p
     
  6. Hero999

    Hero999 Banned

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    Did they explain how it works (in simple terms) and that the energy isn't coming from the potato but from the metals?

    If not, I hope you write in to complain. I don't think they should put misleading things like this on children't TV.
     
  7. Nigel Goodwin

    Nigel Goodwin Super Moderator Most Helpful Member

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    I only saw a small part of it, but they mentioned it was a chemical reaction from the acid in the potato working on the copper and zinc nails used as electrodes, and that the electrodes are consumed in the operation.
     
  8. Mikebits

    Mikebits Well-Known Member

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    I think the potato acts as an electrolyte.
     
  9. Hero999

    Hero999 Banned

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    That's it, all the energy comes from a chemical reaction between the dissimilar metals which comes from the huge amount of energy required to extract and purify them - no free lunch.
     
  10. MADI31

    MADI31 New Member

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    this is an old concept
    i seen a model of this in my school function
    but there is a failure of this concept this cant generate enough electricity not even to charge a3 volt battery
     
  11. Nigel Goodwin

    Nigel Goodwin Super Moderator Most Helpful Member

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    Yes, we all know that.

    Not at all - perhaps you should read this thread, which is about a TV programme which ran a portable radio from it - just to show it could be done.
     
  12. HarveyH42

    HarveyH42 Banned

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    Could you get more energy out of the potatoes, if you converted them to vodka? If you don't sample too much, for huhm, alcohol content... :)
     
  13. mneary

    mneary New Member

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    Since the electrolytic energy comes from the electrodes and not from the potato, when the electrodes have been consumed the potato should still be good for fermentation (unless the electrode material poisons the yeast). You win twice!
     
    Last edited: Mar 6, 2009
  14. Sceadwian

    Sceadwian Banned

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    Copper and Zinc are both EPA regulated metals in water, in an ionic (disolved+active) state they're not so good for you, particularly copper. I'd like to see someone come up with a sane method for making high surface area electrodes for these things though, because the amount of current you can pull off them is limited primarily by the surface area of the electrodes used.
     
  15. Mikebits

    Mikebits Well-Known Member

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    Maybe you could use bigger electrodes with a watermelon :D
     
  16. HarveyH42

    HarveyH42 Banned

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    Are you sure about the copper? My hot water heater is installed with copper pipe, soldered as well, hopefully lead-free...
     
  17. Nigel Goodwin

    Nigel Goodwin Super Moderator Most Helpful Member

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    I imagine it's definately NOT lead free, why would you want it to be?.
     
  18. steveB

    steveB Well-Known Member Most Helpful Member

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    Another way to get the energy out of potatoes is to eat them, and do some work. :D

    The human body consumes about 100 W power on average. One potato keeps you going for about an hour. Not bad!
     
    Last edited: Mar 7, 2009
  19. Sceadwian

    Sceadwian Banned

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    Very sure Harvey, it destroys the liver, it used to be a problem with copper cookware cooking acidic foods, I guess sterilizing milk in copper kettles may be a problem as well.
     
  20. Jules_Theone

    Jules_Theone Member

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    I have lead pipes from my hot water tank in the loft, but I only drink from the cold water tap, and boil water from cold in a kettle (I don't make a coffee from the hot water in the loft)
     
  21. magickaldan

    magickaldan New Member

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    They probably are not lead pipes, lead is to soft to be used as a pipe material, the pipes are probably galvanized steel, is that what you meant? Now it's possible that it has lead joints since many old houses have them; but nowadays it is illegal to use lead in any domestic piping system.



    Heres any idea if anyone wants to try it or has some scrap material to try it with.

    Materials:

    1. Potato
    2. Zinc coated nails, (the thicker the nail the better to increase surface area.)
    3. 1/2 inch copper pipe. (about the same length of the zinc nail)

    If you can scuff up the inside of the 1/2 in pipe first.
    Then take your short piece of 1/2 inch pipe and ram it into a potato so it is completely filled with the potato; Then take your nail and put it directly in the center of the pipe. Simple but effective. I have not tried it yet but I would imagine it would be a whole lot more efficient then just putting two nails or two strips of metal in the potato, distance and surface area are two of the main things in one of these Galvanic cells. The closer the anode and cathode are to each other of course the less resistance there will be thus allowing more current. Some other cells that are interesting are the Daniel Cell, a Voltaic Pile, Lemon Battery. Try them out if you havn't there pretty awesome. :)
     
    Last edited: Mar 13, 2009

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