How Much Exhaust Heat Does a Nuclear Power Plant Discharge Per Hour?

AI Thread Summary
A nuclear power plant operating at 78% efficiency between temperatures of 540°C and 330°C produces electric energy at a rate of 1.3 GW. The calculations show that the total heat input (Qh) is approximately 3.87 x 10^11 J/h. The exhaust heat discharged (Qc) is calculated to be around 1.855 x 10^13 J/h. The discussion reveals a common confusion in the calculations, but the original values were ultimately confirmed as correct. Understanding the efficiency and heat transfer equations is crucial for accurate assessments of energy output and exhaust heat in nuclear power plants.
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[SOLVED] Nuclear Powerplant Efficiency

Homework Statement


A nuclear power plant operates at 78% of its maximum theoretical (Carnot) efficiency between temperatures of 540°C and 330°C. If the plant produces electric energy at the rate of 1.3 GW, how much exhaust heat is discharged per hour?

Homework Equations


1)e=(Qh-Qc)/Qh
2)e=W/Qh
3)e=1-(Tc/Th)

The Attempt at a Solution


e=(Qh-Qc)/Qh, so...
e=[(540+273)-(330+273)]/(540+273)
e=.258302583
e=.258302583(.78) since its operating at 78% efficiency
e=.2014760148
e=W/Qh, so...
.2014760148=(1.3*10^9)(60))/Qh
Qh=3.87*10^11
e=1-(Qc/Qh), so...
Qc/3.87*10^11=(1-.2014760148)
Qc=3.091*10^11
3.091*10^11*60
Qc=1.855*10^13 J/h

I don't know where I went wrong?
 
Last edited:
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nevermind i had it right all along doh!
 
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