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Energy Plant

  1. Mar 20, 2006 #1
    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.
  2. jcsd
  3. Mar 21, 2006 #2


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    And this:
    Are not the same. If your original number is correct, you are a factor of [itex]10^{-3}[/itex] out, which would make your answer $54.001

  4. Mar 21, 2006 #3
    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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