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Making society independent of fossil fuels.

  1. May 5, 2006 #1
    Original here : http://www.everything-science.com/content/view/155/2/

    After reading this , a question sprung into my head : "Where are they going to get that much Hydrogen , to replace all the fossil fuels that are used today ?"

    Any ideas ?
  2. jcsd
  3. May 6, 2006 #2
    Hydrogen can be produced very simply via electrolysis.

    You could even try this yourself. Just take a battery, a couple of wires and a cup of water.... & hey presto, hydrogen and oxygen.
  4. May 6, 2006 #3


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    If that's all it took we'd be winning. You forgot about the energy input needed.
  5. May 6, 2006 #4
    Nuclear power.
  6. May 6, 2006 #5
    That's not a very good idea , since it would make fuel prices go up ALOT , becouse electricity is the most expensive form of energy.

    After looking at some figures , it seems to me that you'd waste more energy producing hydrogen , then you'd get from burning it.So electrolysis definatly isn't a good method.
  7. May 6, 2006 #6
    Firstly, in order to get hydrogen from ammonia you need to put in energy, which rather defeats the point. I would say that hydrogen is just a buzzword here, the real reaction is

    ammonia + oxygen -> nitrogen +water

    As to where you get the ammonia from, well yes you have to manufacture it and that takes more energy that you'll get out. Such technologies are really a method of energy storage, not production. The idea is to use an environmentally friendly source of energy in the manufacture.
  8. May 7, 2006 #7


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    Although mass-production of hydrogen (via electrolysis from seawater, for example) is not 100% efficient, neither is the mass-production of fossil fuels. Besides, the increase in efficiency of fuel-cell vehicles offsets the efficiency hit incurred by electrolysis.

    Keep in mind that the purpose of the hydrogen economy is not to boost overall system efficiency -- it's mainly just to wean us off fossil fuels and rampant pollution. You can generate energy much more cleanly at a centralized plant (even if it's still burning coal) than in a lightweight automobile burning gasoline. That's the point: push the pollution up the supply chain so that it can be better controlled.

    - Warren
  9. May 10, 2006 #8
    wouldnt alcohol be a good alternative source, i dont know the potential evergy of it, but i think ethanol has enough, not sure, tell me if im wrong, but it burns cleanly, and we can produce it rather easily.

    and i dont think getting hydrogen from water will ever be worth it.

    how about nuclear power automobiles? i think that sounds safe...
  10. May 10, 2006 #9


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    No. Nuclear power would have to be limited to RTG's.

    Making a small nuclear reactor requires high enrichment and the smaller the reactor the more difficult the control system. In addition to safety, there would be proliferation issues - cars would likely be stolen for the nuclear material. Plus the infrastructure to support a fleet of nuclear powered cars would be expensive. And most likley a nuclear power car would cost much more than an ordinary consumer could afford.
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