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After Hurricane Sandy A Question about Electricity

  1. Nov 1, 2012 #1
    Ok, I"m from New Jersey, and as you may have heard we've been hit pretty bad. ...After spending 3 days in the dark and cold... I've had some time to ponder. My question is a very basic one. I know that many phone lines and wires are put underground. That's why you see the Bell logo on many manholes. This protects against any damage. So my question is..after storm many storms, why not put electrical lines underground? Wouldn't this prevent like 90% of the outtages?

    And also, what really causes outtages? Is it downed tree's that fall on cables? I thought this as well, but just today, the power in my house, my friends out the next town over, and my girlfriend's house, which is miles away, all got power back at the same time? So what happened here? Clearing they didn't move one tree and miraculously we all got power again. So is there an electrical plant somewhere that was damaged? When power goes out in wide spread area's like what we had here, is it usually the electrical plant that is out?
  2. jcsd
  3. Nov 1, 2012 #2


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    Not if manholes and basements fill with floodwater (as in New York).

    Another issue (in a country like the USA with strong feelings about individual freedom and liberty) could be that underground lnes put more restrictions on what landowners can do with their "own" land than overground lines.

    It could be the high voltage line that supplied a few square miles of country that was damaged. Or if there were many incidents with "small" local danage, it might be quicker to turn the power off to the whole area to let the repair teams work without having to keep checking each separate line was powered off, and then restore power to the whole area when they were done.
  4. Nov 1, 2012 #3
    I'm wondering the same thing :D I'm from Denmark and all our powerlines are dug down :P No problems with water here :D

    There was actually discussion on one of our engineering sites about this. Some people pointed out that whenever anything goes bad or has to be changed, it takes longer time here than in america, since we have to dig it up and such.
  5. Nov 2, 2012 #4
    Really it is all about cost. Underground cables have to be a fully insulated cable - cost much more which may be surprising when you look at poles, standoff insulators - etc. Once installed maintenance costs (if properly installed) are less for underground - and far more reliable in bad weather. Underground cables - do suffer from aging historically, but I think modern materials have generally eliminated that from being a major factor. However if there is a problem repair cost is higher ( per incident).
  6. Nov 2, 2012 #5

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    It's also about fences and driveways, phone companies and cable companies, and, at least in the south, fire ants. People don't like their fences or driveways torn up just so the power companies can put their power cables underground. The problem with phone companies and cable companies is that if they've already gone through that trouble of dealing with fences and driveways, they own the underground easement that the power companies would like to take advantage of.

    Finally, there's fire ants. They have a penchant for committing mass suicide while shorting out underground power cables. There's something about that 60 Hz frequency that just drives them nuts.
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