On 9/27/03 11:38 AM, "Ilan Kelman" <[log in to unmask]> wrote:
> One of the video clips I saw from Hurricane Isabel appeared to be downed
> power lines caught in trees and fluttering in the breeze while sparking and
> crackling. Aside from the potential dangers of electrocution and possibly
> fire (?), the devastating effects of broken lines are shown through at least
> three utility workers who have been fatally electrocuted while undertaking
> repairs. Similarly, in Puerto Rico in 1989, five of the nine fatalities
> attributed to Hurricane Hugo there were electrocutions which occurred while
> repairing downed power lines.
>
> Why do authorities not shut down the power grid as a hurricane approaches
> and refuse to turn it on until repairs are complete? If the grid is not
> designed to be flicked on and off--perhaps a few times a year--why not?
>
> Hospitals, emergency operations centres, and emergency services (should)
> have their own power supplies. If they know that protocols for a hurricane
> include shutting down the main grid, they will (hopefully) prepare for it.
> Similarly, people routinely board up windows and evacuate for hurricanes, so
> if it were standard procedure, they could just as routinely prepare for no
> power. In fact, the hope is that they would be better educated (e.g. don't
> use generators in confined spaces, which has led to numerous Isabel-related
> fatalities, and monitor for candle fires) because it would happen more
> frequently and people would know that power would definitely be out rather
> than being vaguely prepared on the off-chance that power might be cut.
>
> Simple procedure: 12 or 24 hours before landfall, which can be predicted
> reasonably well, turn the power off. Then, take 24-72 hours after the
> hurricane has passed to repair damage before turning the power back on.
> People, many of whom would have been evacuated anyway, would be without
> power for 3-5 days. Not bad once you get used to it and if you have
> prepared adequately.
>
> For example, according to the BBC, for Hurricane Michelle in Cuba in 2001:
> "Electricity in the capital has been cut off to avoid accidents with falling
> power cables" ( http://news.bbc.co.uk/2/hi/americas/1637584.stm ). Cuba's
> energy supply system presumably has differences to the U.S.A.'s, but, in
> principle, deliberately turning the lights out could work. Are there
> examples from other locations?
>
> An immediate technical issue to consider is whether or not adequate testing
> of the repaired system could occur with the power off. But surely that must
> occur frequently and it could not be particularly difficult to work
> something out. Certainly worth a few lives.
>
> As well, considering the megaprojects which currently supply most developed
> world energy, such as nuclear power plants and fossil fuel fired plants,
> shutting them down and starting them up takes time. Yet shutting them down
> quickly could not cause that much of a problem. Witness what happened
> during the blackout in August in eastern North America and the systems which
> Japan uses to automatically shut down plants when a major earthquake is
> detected. Regarding start up, if it takes a day or two to get them
> operating at full capacity, then we should wait. Or improve their design to
> start up more rapidly.
>
> Perhaps the challenges involved are greater than I suggest. If so, I would
> ask again: if the procedure which I outline is not as simple as I think,
> why have we not designed and built our energy system to make it that simple?
>
> Ilan
>
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A couple of things that must be remembered when you start a plan like this.
You cited that some power workers were electrocuted during repairs. One of
the reasons is that people are purchasing generators and providing power for
themselves after the storm. The generators not only power the houses but
they also charge portion of the power lines connected to these house. While
the companies try and get the word out to protect the workers it sometimes
difficult to make sure everyone knows. Not impossible but difficult and
hard to determine it importance with.
Secondly you mentioned the "repairs" taking up to 72 hours. What is
happening now is not "repairs", the damage is so extensive that power
company's must reconstruct the power gird. Not just repair portions of the
grid that were damaged. This is not a new occurrence it has happened after
every major hurricane going back to Hugo. I am not sure of the solution
since when trees are knocked down by the storm they pull overhead power
lines down but they also pull up any buried utilities. So you get it if you
have over head lines or buried lines. And it is not as I have read a matter
of taking better care of the trees. In a hurricane trees are going down in
large number no matter what. Remember within a hurricane there are hurricane
gusts which are 30% higher than the recorded wind speed. In addition, the
hurricane will spawn numerous, sometimes in dozens, tornados. These are not
as powerful as the typical tornado but certainly powerful enough to knock
trees down. After Andrew the U.S Army did studies of it response to the
hurricane. One of the comments I read was from an officer who suggested a
much wider and more detailed study of the damage done by Andrew be done. He
felt the damage caused by Andrew was as close to what a nuclear weapon would
do to a community as you could get without a real explosion. The damage
cause by a hurricane is so complete and wide spread that other types of
disaster pale in comparison. The good news is they are not as dangerous to
human life as many other types of disasters, they are more threat to the
economic life of a community. For example, close to 80% of the small
business that were effected by Andrew never reopened. That is a huge
economic toll.
As far as the injuries from misuse of chain saws, falls from roofs, fires
from candles etc., the media is filled with these warnings before the storm
alls of this yet people continue to do it. But the number people who are
injured and killed due to these types of injuries are down considerably.
Finally, you suggested cutting the power 12 to 24 hours prior to the storm.
With storm prediction still not an exact science and all of the preparations
that must be completed in the last minutes the shutting down of the power
will only increase the impact on the community. Many jurisdictions will
decided to leave the power on until the storm knocks it out so that people
can continue to make their preparations. The public still has a tendency to
wait to make preparations. But other communities are beginning to shut off
power as the storm begins to strike in earnest. It is very much like the
SOP's fire police use during hurricanes. They will stop responding to
emergency calls once the winds have reached a speed that threatens injure
the responders. Drawing a line in the sand on wind speed where you will shut
the power off to a community is a good idea that needs additional
discussion.
Thank you for your thoughts. It is a good discussion to start.
--
Roger C. Huder CEM
[log in to unmask]
321-217-4005
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