Thermal Efficiency of a power plant

AI Thread Summary
The discussion focuses on calculating the thermal efficiency of a power plant with an electric output of 750 MW and a cooling water flow rate of 1.0*10^8 L/hr, entering at 16°C and exiting at 27°C. The key equations used are W = Qh - Qc and n = Wout/Qh. Participants are attempting to determine Qc, the heat flow to the cold reservoir, to find Qh and ultimately the thermal efficiency. The conversion of the cooling water flow rate from liters per hour to megawatts is a critical step in the calculations. Understanding these relationships is essential for accurately determining the power plant's thermal efficiency.
jalamb90
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Homework Statement


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?


Homework Equations


W = Qh - Qc
n=Wout/Qh


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.
 
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jalamb90 said:
...
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?
...
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.
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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