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Does electricty gain / lose power traveling up / down hill? [Not]

  1. Mar 9, 2017 #1
    (I Live in Michigan - no power at home since yesterday, and likely not until Sunday - 4 days, because of high winds.)

    My software genius boss (really, he's very smart,) is trying to tell me that the reason that the power companies do not bury power lines, is because it costs money to push it back uphill into the homes and businesses. He insists that gravity is such a big factor that it's cheaper for the power companies to repair lines every couple years around here, than bite the bullet, and bury them - one and done.

    Assuming, as he contends, that the power plants are situated in locations that allow a minimal "push" to get the power into the big high tension towers, and therefore have a leg up on the gravity part of the equation, I still think he's wrong.

    I have been "playing with" electricty, AC and DC for over 40 years, residential, commercial, even some factory work, and I have never heard this (what sounds like an) outrageous assertion, before.

    The fact that a cursory search of this forums doesn't even bring up a single result tends to make me even more "resistant" to accepting the idea.

    Still, I am humble enough to know that: "There are more things in heaven and earth, than are dreamt of in my philosophy..." (apologies to Shakespeare....) o:)

    So can any of you real scholarly types boil this down to a 30 second irrefutable case for me - either way? I will accept being wrong, if I can understand why. Of course, I'll be thrilled if I'm right, because I'm really hoping it's just more "Junk Science".

    I'm just not buying that electricity is more than marginally affected by an altitude shift of even a few hundred feet, if at all.

    Thanks a "watt".... :wink:
     
  2. jcsd
  3. Mar 9, 2017 #2

    phinds

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    Are you pulling our leg? Could be he's pulling YOUR leg. That is utter nonsense. In fact it is SO nonsensical that I think it falls into the category of stuff we don't even both to debunk.
     
  4. Mar 9, 2017 #3
    I've never heard of this before.
    Maybe you should ask him for a source of relevant information.
    Then again, if he is your boss, perhaps best to forget it.
     
  5. Mar 9, 2017 #4
    I never have either. He tells a story about a local resident selling power back to the electric utility, and selecting the pole that allows for the least rise from his photo-voltaic array, despite a further distance from the house, because he only has a tiny bit more to sell than he needs for personal use. He also claims that the guy is an electrical engineer.

    Phinds may well be right, in that there may be some leg-pulling going on...probably his, by the guy that told him this "scientific fact". Still, if I could throw some hard science at him, it would no longer be a bone of contention.

    As long as I am not an arrogant arse, I don't think I'll generate any hard feelings, by sharing the science with him. Problem is, I don't even know what to use as a search criteria on google.... Suggestions would be appreciated.







    OK, now I have go check my shed for my Smoke-bender, Rope-stretcher, and Snipe-traps.... I think I'll be making a few Craigslist Posts.... :oldlaugh:
     
  6. Mar 9, 2017 #5

    tech99

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    Be careful he doesn't send you out to buy a tin of striped paint!
    Best wishes
     
  7. Mar 9, 2017 #6
    The first thing I tried was "bury power lines"
     
  8. Mar 9, 2017 #7
    Good call. Top article quotes multiple reasons why burying power lines is often impractical - power loss is not mentioned.

    Gotta go load my cannon....

    "On average, EIA (U.S. Energy Information Administration) found, underground lines can cost five to ten times more to build, per mile, than overhead lines."

    Still love some good old science to load my other cannon....what scientific concept makes them immune to the pull of gravity?
     
  9. Mar 9, 2017 #8

    berkeman

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    My thought as well. :smile:
     
  10. Mar 9, 2017 #9
    Or is it that the pull is so infinitesimally small, that it isn't worth considering?

    I don't like the look and feel of this forum, but they recently has a lively discussion on this topic...
    https://www.thenakedscientists.com/forum/index.php?topic=11187.0

    I don't know, it seemed ridiculous at first, but there might be a tiny kernel of truth in his story...
     
  11. Mar 9, 2017 #10

    gneill

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    Consider that drift velocity for electrons in a typical current carrying wire is on the order of 10-5 m/s, and that for 60 Hz AC at least, the electrons simply move back and forth and move less than a micrometer in either direction over a cycle. There's no net movement of the charges over time.
     
  12. Mar 9, 2017 #11

    davenn

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    there is a lot of garbage in that thread ... so many personal views with little science to back it up

    there are tho, a couple of small gems
    An electron has mass and therefore will be affected by gravity ------- you are only likely to see this if the electron is isolated from other forces
    When in a conductor, the electromagnetic forces between electrons and protons ( within/between the atoms) will be so much stronger
    than any gravitational effect so as to render any force of gravity a null effect

    and on top of that you need to understand what @gneill posted above this post .... the electrons in the wire in your house, light, heater etc, etc, never leave that position they have, they just oscillate back and forward, not going anywhere


    Dave
     
  13. Mar 9, 2017 #12

    anorlunda

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    Only 23 days to go until April 1. Think of a good one to get back at your boss. Plan it well. Post here on April 2 how well it worked. :rolleyes:
     
  14. Mar 9, 2017 #13

    berkeman

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    Yeah, maybe do the old "See how the lamp gets dimmer as I carry it up flights of stairs using an extension cord" trick. Have your buddy with a rheostat at the bottom of the stairs adjusting it as you go up the stairs... LOL
     
  15. Mar 9, 2017 #14

    anorlunda

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    How about this one.

    Every day for 2 weeks, add a cup of gasoline to your boss' gas tank, 2 cups ther 2nd day, 3 cups the 3rd, and so on.. Let him brag around the office about his great mileage.

    Then start cutting back a cup a day until zero, then start removing gas, 1 cup the 1st day, 2 cups ... and so on. Make sure that everyone in the office asks him about his great mileage every day. See how long until he figures it out.
     
  16. Mar 9, 2017 #15

    berkeman

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    LOL.

    Did you see that episode of the old US TV series "M*A*S*H" where two of the doctors kept altering the pants waistband of the doctor "Charles" that they didn't like? Hilarious.
     
  17. Mar 9, 2017 #16

    Baluncore

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    I think you should play along with your boss. This is called “Lying for the Whetstone”, where you sharpen your wits by improving on another's lie.

    On 1st April, explain the mechanism to him a being “just like a water siphon”.

    In a circuit, the electrons are pulled uphill in one wire, then flow down in the other. That is a siphon, but height is limited by the vapour pressure of electrons. Luckily the VP of electrons in copper wire is very high so it can handle big height differences without too much energy loss.

    The electron siphon works best in oxygen free copper because the holes left where the oxygen was removed behave like the capillaries in a tree and so can suck electrons to a great height with much less loss. That is why OF speaker cables are so much better than ordinary copper.

    But the real reason why overhead power lines are now preferred is one of public health, due to the U-bend effect. By maintaining positive electron pressure in the U-bend, EMI viruses can be prevented from spreading over the power lines between houses. The insulation on the wires is really just a long thin condom. The first problems with underground power lines were found when the quality of analogue video tape began to deteriorate. That was in the 1980s when transferable noise viruses first developed and spread in residential housing estates that had many tall tower blocks. It was known at the time that the problem could be relieved by placing the power distribution boards on the top floor, but the advent of digital TV and recordings has largely relieved the problem, though some viruses are still present in old equipment.
     
  18. Mar 9, 2017 #17

    russ_watters

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    As was mentioned, with AC the electrons just wiggle back and forth. But even if it were DC, it still wouldn't matter because any loss from electrons moving uphill would be gained back by the electrons in the wire next to it going downhill. Exactly like a closed-loop piping system.
     
  19. Mar 9, 2017 #18

    rbelli1

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    There is also the issue with increased capacitance in underground cables and the resultant loss of efficiency. Some of the increase in cost is likely due to added or more expensive insulation to mitigate this somewhat.

    Worrying about the difference in gravitational potential of electrons is the same as worrying about the earth going the other way when your elevator goes up.

    BoB
     
  20. Mar 9, 2017 #19

    russ_watters

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    It doesn't; counterweight. :wink:
     
  21. Mar 9, 2017 #20

    rbelli1

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    How much does the job pay to add the exact amount of each passenger as they board? And do they get hazard pay when a football team arrives?

    BoB
     
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