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

S

Skybuck Flying

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.
 
U

Uwe Hercksen

Skybuck said:
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.

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
 
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
 
H

hamilton

Or what dropping that much load all at once would do the the
generators.

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
 
M

miso

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

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.
 
R

rickman

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

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
 
J

Jamie

Skybuck said:
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.)

Too bad they missed!
This could have prevented the power transformer from blowing up.

Bye,
Skybuck.

Jamie
 
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.

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 :)
 
T

tm

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 :)

Most power outages are caused by tree huggers.
 
S

Spehro Pefhany

Most modern day (built in the last 40+ years) residential areas in
Phoenix have underground electrical distribution, and we experience
only around 8.29" of rain annually (30 year average).

Yet corrosion is still a maintenance problem.

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
 
S

Skybuck Flying

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.
 
S

Skybuck Flying

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.
 
And if it was all underground could anyone guarentee the water would
not get into the 500000 volt system with resultant damage??? :-?

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.
 
We do have hurricanes, tornadoes, brutal winter storms, lightning,
floods, earthquakes, and the occasional tsunami. And lots of trees to
fall over on things.

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.
 
G

Greegor

On Nov 1, 6:19 pm, Jim Thompson <To-Email-Use-The-Envelope-I...@On-My-
Web-> Most modern day (built in the last 40+ years) residential areas
in
Phoenix have underground electrical distribution, and we experience
only around 8.29" of rain annually (30 year average).

Yet corrosion is still a maintenance problem.

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?
 
S

Spehro Pefhany

Some of the drones are helicopters. There are some tiny, bird-sized,
battery-powered helicopter drones.

I recently saw a consumer heli tied together with VR glasses. You can
fly like a bird*!

* or something
 
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.
 
J

josephkk

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.
Where is this documented?

?-(
 
J

Jasen Betts

And if it was all underground could anyone guarentee the water would
not get into the 500000 volt system with resultant damage??? :-?

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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