The cost to transmit the energy to the city each hour is $534.944.

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The discussion centers on calculating the potential provided to a city from a power plant located 121 km away, with a high-voltage transmission line carrying 1530 A. The effective resistance of the line is determined to be 2.05 Ω/km, leading to a potential of 3720.484 kV at the city. Additionally, the power dissipated due to resistive losses in the transmission line is calculated at 5.8 x 10^8 W. There is confusion regarding the cost of transmitting energy, with a participant incorrectly calculating the hourly cost based on power units, leading to discrepancies in the expected results. The correct understanding of power units and their conversion is crucial for accurate cost estimation.
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A) An energy plant produces an output potential of 4100 kV and serves a city 121 km away. A high-voltage transmission line carries 1530 A to the city. The effective resistance of a transmission line [wire(s)] is 2.05 Ω/km times the distance from the plant to the city. What is the potential provided to the city, i.e., at the end of the transmission line?

Answer: 3720.484 kV

B) How much power is dissipated due to resistive losses in the transmission line?

Answer: 5.8 x 10^8 W

C) Assume the plant charges $0.093 / kW x hr for electric energy. At this rate, how much does it cost to transmit the energy to the city (by the transmission line heating the atmosphere) each hour? Answer in units of dollars/hr.

This is the one I'm stuck on. I thought that I was supposed to mutliply 5.8 x 10^5 kW with $.093 but then I get $54001 per hour and that just does not seem reasonable.
 
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This:
AdnamaLeigh said:
Answer: 5.8 x 10^8 W
And this:
AdnamaLeigh said:
Answer: 5.8 x 10^8 kW
Are not the same. If your original number is correct, you are a factor of 10^{-3} out, which would make your answer $54.001

-Hoot:smile:
 
I don't quite understand what you mean. I know that those two numbers are not the same. When I changed it to kW, I subtracted 3 powers from the exponent.

Either way, $54.001 isn't the answer, I checked and it failed.
 
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