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Transmission line

  1. Nov 27, 2013 #1

    i would like to know what is the different between 300km and 150km in transmission line..
  2. jcsd
  3. Nov 27, 2013 #2

    jim mcnamara

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    Staff: Mentor

    What kind of characteristics are you asking about? Line loss? There is a practical limit to the length of a transmission line, substations and ties affect transmission lines as well.

    Could you please be a lot more specific? example: How many Kv? What are you trying to learn about?
    This will help you to think about what you want to ask:

    As a side note: Rio Grande Electric Cooperative has the single longest transmission line in the US (As of 1995).
    It was nicknamed 'Old Leaky'. If I remember correctly, it had line losses on the order of 15%. Rio Grande, to my knowledge, has never done well financially. I think the line has something to do with it. With the measurement of customers per mile of line, it was also awful - about .5 customer meters per mile. Most meters were lumped in a few small developments in the Big Bend Park.
    Last edited: Nov 27, 2013
  4. Nov 27, 2013 #3

    I'm not asking for line loss, I'm asking like what is the main different between both of the lines..
  5. Nov 27, 2013 #4

    jim mcnamara

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    Staff: Mentor

    None, except increased line loss and side effects like cost of maintenance. Line loss is a function of distance, AC vs DC, conductor types, coronal loss, voltage, etc. Line length(resistance / impedance) is the primary factor after AC/DC and voltage.

    So, your question, as asked, makes little sense to me. Unless you are referring to impedance or resistance....

    Since you refuse to consider line loss (impedance/resistance, etc), the answer is: no difference.

    Is this a homework question of some sort?
    Last edited: Nov 27, 2013
  6. Nov 27, 2013 #5


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    Science Advisor
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    2017 Award

    since you don't want to consider the electrical differences

    the difference in this context is 150 km :tongue:

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