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Ways to generate clean electricity?

  1. Jan 18, 2007 #1
    Ways to generate clean electricity?
    I’ve been working long on this one, I’m working on a project to generate electricity from every but fossil fuels, don’t want to pollute our world any more with Carbon dioxide //CO2

    What about using water to convert to hydrogen and oxygen and then use that to fuel my combustion engine.
    Will that work or will it only make things run in loops and get no where

    I’ve tried a test with water it takes up 10 sec @28v //0.30A to generate hydrogen and oxygen and then one spark to pop of the lid from the small container, will that be possible to generate electricity from that.
  2. jcsd
  3. Jan 18, 2007 #2


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    So, you propose to use electrolysis to convert water into hydrogen and oxygen, then ignite this mixture to produce water again?
  4. Jan 18, 2007 #3
    Yip, your 100% correct and in the process I’ll probably could capture some energy, will it work
  5. Jan 18, 2007 #4


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    No unfortunately not, electrolysis is only around 40% efficient (if memory serves); you would use more energy obtaining the hydrogen and oxygen than would be produced when you ignite it. Sorry to burst your bubble :frown:
  6. Jan 18, 2007 #5
    The easiest, allmost clean fuel to use in cars would probably be ethanol.
    Allmost all petrol cars can use it with very small modification.

    But if you want stationary power generation there are other clean ways like sun power, wind power, water power or combinations of those.
    Last edited: Jan 18, 2007
  7. Jan 18, 2007 #6
    Jac, there is a question you should ask yourself: Where did you obtain the electrical energy to separate the water? Was it from a coal power plant?
  8. Jan 18, 2007 #7


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    Clearly, Jac believes that you don't need a coal power plant to make the hydrogen (except perhaps for startup), you just use the electricity from your generator.

    Jac, the chemical process goes like this:

    2H2O + E -> 2H2 + O2 (electrolysis)
    2H2 + O2 -> 2H2O + E (combustion)

    Notice that the equations are exactly the same, but reversed. So even if all of your various devices were 100% efficient (and they aren't anywhere near 100% efficient), you'd only ever get out of this what you put into it.

    There is no free lunch. That's the first law of thermodynamics.

    Variations of this quesiton are so common, so simple (you learned this in 8th grade), and so useless (people often spin their wheels for lifetimes trying to beat the first law of thermo), we don't discuss it here. It is a waste of your time and ours.
    Last edited: Jan 18, 2007
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