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Why not turn off power grid one hour before hurricane sandy ?

Discussion in 'Electronic Design' started by Skybuck Flying, Oct 31, 2012.

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  1. Hello,

    I was wondering to myself before Sandy hit if the power grid in New York
    should be turned off, to prevent casualties/deaths and ofcourse damage.

    (Wow this message got interrupted by a red heli flying above my appartment
    complex twice, it was quite close, fortunately I am still alive lol.)

    This could have prevented the power transformer from blowing up.

    Bye,
    Skybuck.
     
  2. Uwe Hercksen

    Uwe Hercksen Guest

    Hello,

    if you want to restore power after the hurricane as quickly as possible,
    you have to test a lot of high voltage components for damages, water and
    ground faults. If you don't test all components, may be some parts will
    blow up when power is restored again. It is difficult to find a strategy
    that both saves time to restore power and keeps the number of destroyed
    components low. Customers will protest if power is turned off long
    before the hurricane hits the city.

    Bye
     
  3. Guest

    Life Support applications. You just forced a transfer to a short lived back up source. Not to mention the massive startup surge needed when dumping power into rotary loads.

    Steve
     
  4. hamilton

    hamilton Guest

    You would think that they (power companies) would have thought of that.

    This is not the first time power has gone out on a massive scale.

    How did it come up the last time ?

    h
     
  5. miso

    miso Guest

    Actually they did shut down the generators that they expected to get
    flooded. The idea was they didn't want the cold water to hit the steam.
    However, this storm produced water levels that exceeded predictions. As
    you know, there is 4% more water vapor in the atmosphere now as compared
    to 40 years ago. So your once in a century storms are now much more common.
     
  6. rickman

    rickman Guest

    Power companies think about this a lot. The trouble is that no matter
    how much you think about it, the physics don't change.

    My understanding is that they bring power up in smaller pieces to
    prevent overloading the generation capabilities. As to shutting down
    the power before? Well, I think the damage caused by leaving the power
    on may be less than the damage done by turning it off.

    Rick
     
  7. Jamie

    Jamie Guest

    Too bad they missed!
    Jamie
     
  8. Guest

    If your state network is down every few years due to hurricane winds
    or icing, why not build some kind of underground HVDC cable network ?

    This would be cost effective in the long run.

    If I understand correctly, the US electric network is so unreliable,
    that a lot of private people actually have their own diesel
    generators.

    In more technically advanced countries, small diesel generators are
    mainly used in hospitals and as emergency cooling systems in nuclear
    power plants, but not much more than that :)
     
  9. tm

    tm Guest

    Most power outages are caused by tree huggers.
     
  10. Back in my college days in the 1970s (Rochester, NY), the college had
    undergrounded all of the power feeders to the dorms and to large parts
    of the academic quarter. They knew about the bad winters there... and
    I can't recall our ever having a significant electrical power outage
    during the winter storms.

    On the other hand... every second year, during the spring rains, I
    could figure that there would be at least one substantial outage in
    the dorms, when the main power line running underground around the
    back side of the dorm complex would suffer from water ingress and
    would short out. RIT is built on barely-reclaimed swampland :)

    A significant outage, for a similar reason, would hit the computer
    center on roughly the same schedule. Every two or three years, it
    would be "Roll the back-hoes out, boys!" time.

    Yes, underground wiring is less vulnerable to wind, trees, and ice.
    On the average, though (from what I've read recently) it doesn't last
    as long as above-ground wiring, and thus requires more frequent
    maintenance. It's also significantly more expensive per mile than
    pole wiring.

    I think it's a tradeoff with no clear winner. Above-ground wiring
    lasts longer on average, is less expensive, but when bad-weather
    outages occur they tend to occur in bunches (trees down due to wind,
    etc.) and a larger fraction of the power distribution grid in the
    affected area goes down. Underground wiring may be less prone to
    these mass-damage incidents, but has more outages over time due to
    cable corrosion and water ingress.[/QUOTE]

    Interesting story:-

    http://articles.baltimoresun.com/20...nd-wires-20120712_1_wires-poles-baltimore-gas





    Best regards,
    Spehro Pefhany
     
  11. R.I.P.:

    "Neighbors Recall Horror of Seeing Woman Electrocuted During Hurricane
    Sandy"

    "
    Read more:
    http://www.dnainfo.com/new-york/201...trocuted-during-hurricane-sandy#ixzz2B2SoWRhi
    SOUTH RICHMOND HILL — Neighbors on Thursday recalled watching in horror when
    a Queens woman was electrocuted earlier this week while trying to capture
    footage of Hurricane Sandy.

    Lauren Abraham, 23, was barefoot in her front yard at 105-05 134th St.
    shooting video of the storm on her iPhone about 8:30 p.m. when she tripped
    and fell on a power line that had been knocked down by heavy winds, police
    and neighbors said.

    "All we heard was one last scream," said Renny Bhagratti, who was watching
    helplessly from his second-floor window across the street. "She dropped back
    like a dead sack of potatoes."

    Another man, whom neighbors identified as Abraham's boyfriend, was trailing
    just a few yards behind with a video camera. Cops arrived at the scene
    moments later and were able to stop Abraham's boyfriend from grabbing onto
    her, said Michelle Stephenson, 40, another neighbor.

    "They saw him trying to get after her, and they managed to tackle him and
    hold him back," Stephenson said. "If not for that, we could be talking about
    two people dead here today."

    The electrocution left a large black charred mark at the foot of the
    driveway, which neighbors said was a chilling reminder.

    "My whole family hasn't slept, hasn't eaten," Bhagratti said. "We're all
    trying to forget what happened."

    Bhagratti described Abraham as a thoughtful, polite young woman, and that
    her mother was working in a Connecticut hospital at the time of the
    incident. She was in disbelief when Bhagratti and his wife broke the news to
    her.

    "She got weak at her knees and collapsed in the middle of the street,"
    Bhagratti said. "She said, 'Not my Lauren. Please not my Lauren.'"

    Abraham's family was in front of her home Tuesday but was too distraught to
    speak with reporters.

    "I can't believe that," Abraham's devastated brother said over and over.

    Stephenson said she was horrified Abraham had "paid such a horrible price"
    for venturing out into the storm.

    "It's moments like these," Stephenson said, "where you say, 'Well I have no
    power, I have no heat, but I have my life.'"

    "

    Another person killed by Steve Jobs's invention ! LOL.

    Perhaps she wasn't too bright, none the less I feel sorry for her ! ;)

    Bye,

    Skybuck.
     
  12. Wow there is an actualy pictures of the execution-aftermath.

    A big black spot.

    http://assets.dnainfo.com/generated/photo/charred-pavement-13517273155474.JPG/image640x480.jpg

    http://assets.dnainfo.com/generated/photo/charred-pavement-13517273143885.JPG/image640x480.jpg

    I have never seen something like that before !

    Wow, can't believe they showed it, but I guess it's healthy for the mind.

    Perhaps this will make people reconsider in the future ! ;)

    It's almost like "final destination"-movie ;)

    Anybody want some fried nigger ?! ;) OHOHOHOHOH.

    Bye,
    Skybuck.
     
  13. Guest

    There are quite a lot HVDC cables crisscrossing the seafloors of both
    the North Sea as well as th Baltic Sea. Most of the problems has been
    with the on shore equipment.

    I agree that earthquakes could be a problem for underground lines,
    especially when crossing a fault line, in which a few poles with lots
    of slack might be needed.
     
  14. Guest

    Trees should not be an issue on the high voltage network, since there
    needs to be on high poles and the rights of way should be wide enough,
    so that any tall trees that could fall over the lines, should be cut
    down well in advance.

    Trees are a problem for the low voltage wires and especially to the
    medium voltage open wire lines feeding the local distribution
    transformers. Low voltage cables suspended on poles will usually
    tolerate one or two trees leaning on the cable, but the thin medium
    voltage open wires will snap even with a small tree is falling over
    the wire.

    The low (2x120 V) distribution voltage in the USA, compared to 230/400
    V in Europe, dictates that the distribution transformer must be quite
    close to the customer, which means that there must be a huge number of
    small distribution transformers all over.

    This creates an other problem, how to feed these small transformers at
    medium voltages (a few kilovolts).

    This requires a huge medium voltage networks with medium voltage
    (usually open wire) feeders every few street and hence the total
    length of the medium voltage lines for a given area is quite large
    compared to Europe.

    Hence we see news clips with lots of blue flashes whenever there is a
    hurricane in the USA, when those open wires hit each other.
     
  15. Greegor

    Greegor Guest

    Aren't they replacing those with domestic DRONES?
     
  16. Greegor

    Greegor Guest

    On Nov 1, 6:19 pm, Jim Thompson <[email protected]
    Web-> Most modern day (built in the last 40+ years) residential areas
    in
    If corrosion underground is that bad in Phoenix
    then it would be absurd in most other places,
    or is the soil pH in Arizona making it worse?
     
  17. I recently saw a consumer heli tied together with VR glasses. You can
    fly like a bird*!

    * or something
     
  18. Guest

    On Wednesday, October 31, 2012 4:55:43 AM UTC-4, Skybuck Flying wrote:

    They did perform a preemptive shutdown for the big stuff that was certain to be damaged:
    http://www.csmonitor.com/USA/Latest...Hurricane-Sandy-Lights-out-in-Lower-Manhattan

    From what I'm reading, it is the distribution substations that are the most time consuming repair, sometimes taking months if the damage is severe enough.

    The other miscellaneous damage due to trees, toppled poles, and that kind of thing is nickel and dime and handled on a case by case basis.
     
  19. josephkk

    josephkk Guest

    Where is this documented?

    ?-(
     
  20. Jasen Betts

    Jasen Betts Guest

    sure, buried cables are built that way.

    Only problems with buried power is accidental excavation.
    earthquakes, and other underground disasters (sinkholes, landslides etc)
     
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