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Homework Help: Heat engines

  1. Oct 9, 2004 #1
    Hi, I am stuck on the question, I don't require the solution, just how to get started.

    A power plant's electrical output is 750MW. Cooling water at 15oC flows through the plant at 2.8x10^4 litres/sec and its temperature by 8.5oC. Assuming the plants only energy loss is to the cooling water and that the cooling water is effectively the low temperature reservoir, determine:

    1. the rate of energy extraction from the fuel
    2. the plant's efficiency.

    Cheers
    Greg
     
  2. jcsd
  3. Oct 10, 2004 #2

    Clausius2

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    Science Advisor
    Gold Member

    What do you mean?. IF you're meaning [tex]\Delta T=8.5ÂșC[/tex] is the increasing of temperature of that water, then:

    Power extracted of the fuel: [tex] W=W_{electric}+W_{losses}[/tex]

    The losses to the environment can be calculated:

    [tex] W_{losses}=\rho Q c\Delta T[/tex]

    as a function of the volumetric flux Q, density and heat capacity.

    Go ahead!!.
     
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