Quote:
Originally Posted by aberdeen5698
It takes one day to swap the pole - I watched them do it behind my house a couple of years ago and shot a time-lapse video of the process. It's actually quite clever how they do it.
The video: http://www.youtube.com/watch?v=u0Knzw5a56M
I believe the pole in question was an original one for our street which would place it at circa 1949.
The reason they leave the stub pole there is because it carries not just the hydro power lines but also the Telus and Shaw phone and cable lines. They're not authorized to monkey around with those other companies' infrastructure. So the leave those lines attached to the old pole until the other companies come along and move them to the new one, then they gather up the old poles.
I've never seen toppled utility poles after a storm, either. Trees come down because the branches and leaves catch the wind, but that's not an issue with utility poles.
Also, you need to bear in mind that the 220V feeder lines that run down the laneways are fed from transformers connected to a high voltage line (50KVolts, I think?) that runs along the very tops of the poles. Using metal poles may pose some challenges in terms of dealing with those kinds of voltages in a fashion that doesn't compromise safety for the people at the bottom of the pole. Note in the video how much distance there is between the three wires that carry the 220V power and the high voltage line at the very top. It would be difficult to provide that isolation distance on a metal pole.The people who run utilities all over the world aren't dummies. If they thought they could do it cheaper with metal poles I'm sure they wouldn't hesitate to use them. |
Interesting video you posted there. I think I mis-spoke in saying it takes "
at least 2 days" to change to pole. I should have said it takes "
at most 2 days". The ones in my alley were done this summer too, so I had the privilege of watching the process too. 2 days.
Also interesting to learn from you about the utilities not being allowed to touch or move the other utilities' wires.
I have seen many toppled wooden poles. You may not have. But it does definitely happen. Again, in my neighbourhood, I had to navigate one earlier this spring. Sometimes it's because the top portion is weakened from animal attack (I would assume woodpeckers, rot, and possibly insects making holes), so it takes some external forces to break them. Also, if a large enough tree branch topples onto wires, it can break the top of the pole. Seen that too.
I don't think a metal pole carrying live wires is innately more dangerous than a wooden version. The cables are insulated, their contacts to the pole are insulated, and high-tension cables all around the world have been made of metal for years and years. Yes precautions would need to be placed, but the risk is not from an increased chance of electrocution from touching the metal pole at the bottom
Finally I don't assume the people who run utilities are dummies either. However, new technologies come along, and companies have a habit of sticking with what they know, unless presented with a clear cost-saving alternative. For all we know, the utilities are considering metal poles but just haven't started the process of installing them yet.
After doing some initial googling, there are lots of companies that offer metal power poles as an alternative to wood, and state, just as I had surmised, that over the long term, metal poles end up cheaper than wooden ones. In fact, a US steel lobbying organisation (obvious biased noted) claimed close to one million steel poles have been installed since 1998, and are used in 600 of 3100 US electric utilities (an interesting set of links here:
https://www.steel.org/The%20New%20St...y%20Poles.aspx)