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Clean energy and more drinking water.

  1. Apr 7, 2008 #1
    Ok, as usual I might have gotten a concept wrong here, I usually do. If that is the case then please point it out to me.

    The "natural" state of hydrogen and oxygen is to combine to H2O. That is, if you put them in proximity they react together to form said molecules. Now, we can use energy to separate the two, and thus have created "potential chemical" energy. (I don't know if this is the term, but I compare it to separating two magnets. You use energy to pry them apart, and then it is released when you let them snap back together).

    One way to separate Hydrogen from Oxygen is to use electrolysis. As far as I can understand, this effect will work regardless of impurities, so you can perform this on saltwater?

    So, I gather that something like this would work:

    You put a turbine on a river, close to an ocean. You use the electricity from said river/turbine to perform electrolysis on the saltwater, and store the Hydrogen / Oxygen in separate tanks. You now have a very portable source of energy which can be used to power small devices that are either mobile (cars) or otherwise unable to connect directly to a riverside turbine.

    The kicker is that in addition to 100% pollution-free energy, you are actually creating drinking-water from salt-water! The exhaust from the devices run on hydrogen could be used to provide fresh water where it is currently too little. And I understand that salt can somehow be used for clean energy as well? (someone please tell me what this is called or give me a link if you have one). If this is true then electrolysis of salt-water would solve a whole wide range of problems.

    You can even go one step further and say that nothing can connect directly to the turbine. IE, even a plant generating power to a city needs to go via the Hydrogen. This is less efficient of course, but it generates a lot of fresh water.

    Then comes the question. If what I have said so far is true, what is indeed stopping us? Is it simply a matter of economics? Is it cheaper to use the turbine to do things like extract/refine oil? If that is the case, could not the governments in rich countries simply ban the use of fossil fuels? If the net energy of current turbines are not enough to generate the hydrogen that we need, can we not simply build more? (substitute turbine for solar cell where there is much sun and few rivers.. we all have salt-water).

    Any and all input on this is appreciated.

    Last edited: Apr 7, 2008
  2. jcsd
  3. Apr 7, 2008 #2


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    Staff: Mentor

    There are two things stopping us from using the concept you describe:

    -We already are utilizing the available hydroelectric power to about it's limit.
    -It is cheaper and more efficient to just use the electricity from hydro power as electricity.
  4. Apr 7, 2008 #3
    Can you elaborate on that? I'm not sure I understand what you mean. ..that we have depleted most of the efficient sites for dams? The turbine could be replaced by a solar cell, or a wind mill or a tide-turbine and so on.

    Aye, I see this one. I was about to object that this does not take mobile devices into account, but then I realized it is just a matter of making electric cars instead. Good point indeed, why go through any storage medium other than a rechargable battery.

  5. Apr 7, 2008 #4


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    Staff: Mentor

    That's exactly what I mean.
    Yes, there are other ways to produce electricity. Nuclear power comes to mind as well. But in order to be a good idea, it needs to provide some advantages over current methods, such as cost and/or cleanliness. As about half of our electricity currently comes from coal, any pollution benefit of a clean energy source should first be used to offset that pollution. And since coal is cheap, it will take a relatively cheap replacement to avoid a huge hit to the economy. Only nuclear power can provide both of those. So in my opinion, we should consider using our nuclear plants to produce hydrogen only after we've tripled the number we currently have and replaced all of our coal burning plants with them.
    Hydrogen does have some advantages over batteries, but efficiency isn't among them. And similar to what I say above, any advantage only realy starts to kick in after our existing electrical infrastructure is fixed.

    We may one day use hydrogen to power our cars. I personally do not forsee it being viable for at least another 30-50 years, which is about how long it could take to ramp up our nuclear power industry if we put a reasonable effort into it.
  6. Apr 7, 2008 #5


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    Gold Member

    The electrolysis idea is a good one for providing a drinking supply. On the other hand, if you have a river there to provide the power, it's already fresh water. It might be more practical to just purify that by established water-treatment protocols.
    If there's no river, then something like wave-power would be a reasonable way to produce electricity.
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