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Homework Help: Thermal Efficiency of a power plant

  1. Apr 27, 2010 #1
    1. The problem statement, all variables and given/known data
    The electric output of a power plant is 750 MW. Cooling water flows through the power plant at the rate 1.0*10^8 L/hr. The cooling water enters the plant at 16 degrees C and exits at 27 degrees C. What is the poer plant's thermal efficiency?


    2. Relevant equations
    W = Qh - Qc
    n=Wout/Qh


    3. The attempt at a solution
    w=Qh-Qc
    790MW=Qh-Qc
    tried to solve for Qc in order to find Qh but couldn't figur out how to get Qc from 1.0*10^8 L/hr to MW.
     
  2. jcsd
  3. Apr 27, 2010 #2

    Andrew Mason

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    Homework Helper

    What is the rate of heat flow to the cold reservoir (how much heat does it take to raise 10^8 L of water from 16 to 27 degrees C. ?)

    That will give you Qc which will then enable you to find Qh and the efficiency.

    AM
     
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