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Ok where does the energy come from?

  1. Aug 25, 2009 #1
    http://www.statkraft.com/pro/press/Press_releases/2007/Statkraft_to_build_world_s_first_osmotic_power_plant.asp [Broken]

    Just heard about this on a UK T.V programme. It described an osmotic pressure power station described in the link above. It works by alternating chambers of "pure" and salt water, seperated by a semi-permeable membrane. As water moves into the salt water chambers the pressure build until water is expelled driving a turbine. Great but where does all this energy come from?
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Aug 25, 2009 #2


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  4. Aug 25, 2009 #3
    The article goes over what I already know and does not address where the energy comes from. The ouput K.E of the tubine comes from somewhere. To say is comes from the pressure difference between the saline and pure water is not enough for me.

    Can anyone eleaborate. Maybe I am asking the wrong question.
  5. Aug 25, 2009 #4


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    Of course it does:
    Usually energy from the sun separates water from salt and can be retrieved by this technology.
    Last edited by a moderator: May 4, 2017
  6. Aug 25, 2009 #5


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    Ultimately the energy came from the sun evaporating sea water and dropping it on land as rain.
    It's basically the same as hydroelectric power but instead of using the difference in height it uses the difference in salinity.
  7. Aug 26, 2009 #6
    OK, I just did not read it well enough.
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