
Utility poles - pavel_lishin
https://blog.plover.com/tech/utility-poles.html
======
adonovan
Those cans are filled with transformer oil, which until relatively recently
consisted mostly of polychlorinated biphenyls or PCBs. Imagine how many of
those cans exist across the United States and you get a sense of how big the
PCB industry used to be, and why rivers such as the Hudson in New York [1] and
the Housatonic in Massachusetts [2] are polluted with olympic swimming-pool
sized quantities of the durable oily poison.

PCBs were used because they are really good thermal conductors, which is the
same property desired of cooking oil for frying. In recent years, thieves in
Kenya (which has yet to replace PCBs with something less toxic) have been
vandalizing [3] transformers and selling the oil to street vendors, which has
the twin effects of destroying the fragile electrical infrastructure and
poisoning the neighborhood.

[1]
[https://en.wikipedia.org/wiki/Pollution_of_the_Hudson_River](https://en.wikipedia.org/wiki/Pollution_of_the_Hudson_River)
[2] [https://www.epa.gov/ge-housatonic/understanding-pcb-risks-
ge...](https://www.epa.gov/ge-housatonic/understanding-pcb-risks-ge-
pittsfieldhousatonic-river-site#FastFacts) [3]
[https://www.reuters.com/article/kenya-electricity/thieves-
fr...](https://www.reuters.com/article/kenya-electricity/thieves-fry-kenyas-
power-grid-to-cook-fast-food-idUSL6N0U81JB20141227)

~~~
js2
There's a nice recreational lake here in Raleigh, NC. People run on paths by
it, sail on it, and used to fish out of it. Sadly, it’s also an EPA Superfund
site because a company long since out of business, Ward Transformers, saw fit
to dispose of PCB-laden transformer oil right into a ditch behind the plant.
The PCBs ran off into the lake and streams for miles. All the nearby waterways
warn not to eat the fish caught therein.

This company wasn’t just irresponsible, it was malicious. At one point, a
contractor it hired to dispose of the oil was caught spraying it along rural
roadsides.

[http://sph.unc.edu/superfund-pages/srpresources/ward-
transfo...](http://sph.unc.edu/superfund-pages/srpresources/ward-transformer-
superfund-site-resources/)

[https://sph.unc.edu/files/2015/08/SRP_Soil-Still-
Toxic-25-ye...](https://sph.unc.edu/files/2015/08/SRP_Soil-Still-
Toxic-25-years-later.pdf)

Related story – “How the Benzene Tree Polluted the World“:

[https://www.theatlantic.com/science/archive/2017/10/benzene-...](https://www.theatlantic.com/science/archive/2017/10/benzene-
tree-organic-compounds/530655/)

~~~
mirimir
Dirt and gravel roads were commonly oiled to keep down dust, and eventually
create something like macadam. But they tended to use the least expensive oil
available. Such as used motor oil. Which, back in the days of leaded gasoline,
contained considerable lead.

------
Waterluvian
I absolutely love reading about a topic from a super enthusiastic non-expert.
I want to subscribe to a weekly series called "Reasonably Intelligent Person
Obsesses Over Something"

~~~
philg_jr
Something that completely fascinates me are cell towers/equipment. They are
everywhere, yet I know almost nothing about them and rarely get to see them up
close. Even less often (pretty much never) meet anyone who work on the
equipment. I imagine each base station is basically a mini datacenter. I was
at Mammoth Mountain recently for the first time and got to see the cell towers
at the top of one of the lifts up close and got some good pictures.

~~~
pdelbarba
I would absolutely love a big writeup on how they're set up and what the
components are, as well as all the real-estate stuff that certainly surrounds
them. I'm also noticing a lot of new towers that look like big cylinders on a
pole, sort of like a TACAN so I often wonder what's up with that.

I do know that the traditional ones are triangle shaped such that they each
form the intersection of a hexagon tessellation (hence the cell in cellphone)
such that you have three towers pointed into every hexagonal cell.

~~~
eptil
The cell companies are actually moving away from the large towers as 5g
service is deployed in favor of microcells.

[http://www.steelintheair.com/Blog/2017/04/top-10-things-
the-...](http://www.steelintheair.com/Blog/2017/04/top-10-things-the-wireless-
industry-doesnt-tell-you-about-small-cells.html)

They can be built into decorative lighting poles such that you would really
have to pay attention to notice them.

~~~
derefr
How does that work in rural areas? Microcells all the way down the highway at
regular intervals?

~~~
pngai
Microcells are good for carrying lots of traffic from lots of mobile stations.
In rural areas, coverage at the lowest cost per square mile is more important.
Also, farmers aren't always near the highway, so microcells on the highway
would not work well for them.

------
Dangeranger
Back around 2010 I worked for a company which built software to catalog
residential distribution utility poles and the lines emanating from the poles
to the houses.

To elaborate on a few of the statements from the post

    
    
        Poles in my neighborhood tend to have consecutive numbers. I don't think this was carefully planned.
    

The sequential ordering of pole numbers is definitely planned, and fits in
with a scheme developed back in the 60s-70s which made documenting the poles
lifecycle in paper records much easier. The poles are numbered sequentially
with prefix numbers generally indicating which substation district the pole
belongs within. Distribution utilities think about their infrastructure as a
network of substation circuits. You should be able to tell which circuit you
are on based on the numbering on the pole.

    
    
        There are three because that is one way to change the three-phase power to single-phase, something I wish I understood better. Truly, we live in an age of marvels.
    

Not all distribution systems use three phases, some use two, some use single.
It all depends on where you are in the system and the general layout of the
circuits within the distribution network. Also not all distribution is 7kV,
some are 12kV, and some are 25kV. Again this all changes based on the
properties of the system, and the qualities that are being optimized for by
the power engineers.

    
    
         I have tried to imagine what the number-burning device looks like, but I'm not at all sure. Is it like a heated printing press, or perhaps a sort of configurable branding iron?
    

This can be done a number of different ways, but one of the common ways is
with a laser engraver. This is a fairly recent practice, so I am not as versed
in the operational details as with traditional tagging. Another means of
tagging which is not covered in the article is carving the numbers into the
pole with a physical etcher, similar to a wood router.

    
    
        Without the Internet I would just have to wonder what these were and what OSMOSE meant.
    

OSMOSE was at the time of my work in this field, the largest such company that
dealt in the support and maintenance of residential utility poles. They have
some very interesting proprietary mechanisms for managing inventories, and are
generally a very smart group of people. My guess is that they collect all the
inventory and survey maintenance of poles using mobile LiDAR and machine
vision now, as that was what we were speaking to them about at the time.

~~~
jmspring
The pole numbering also helps in things like the work PG&E has to do checking
for trees and other obstacles posing a risk to transmission lines. The report
indicating where the work needs to be done (for instance to cut down a tree)
uses the pole number as a point of reference.

~~~
Dangeranger
Yes, I am intimately familiar with this as this was also part of the services
that I was involved in delivering. One of the deliverables for utility clients
we provided was every "fall in" or "drop in" line violation for high power
transmission lines, including their "between" location in relation to adjacent
poles on the corridor.

I could talk about this subject for hours so let me know if you have any other
questions.

:)

~~~
lovemenot
What's a typical range of amperage for a distribution line?

~~~
Dangeranger
Most distribution transformers have a maximum rating of 200kVA. So depending
on their voltage you can calculate the max amps by (200kVA / voltage). Minimum
amps is a bit harder to calculate but I would make a best guess of 20% of the
max 200kVA.

You can read a bit more about the calculations here[0]

[0]
[https://yorkcentraltechtalk.wordpress.com/2012/06/27/transfo...](https://yorkcentraltechtalk.wordpress.com/2012/06/27/transformers-
and-va-ratings/)

Edit: noted that 200kVA is the maximum rating, not default rating.

~~~
phasetransition
Do the distribution transformers have "winter" ratings like the local center
tapped step down transformers that feed houses? Around here it is pretty clear
that Georgia Power doesn't pay much attention to the name plate ratings,
winter or otherwise, when sizing and determining the number of homes per
xformer.

~~~
shaneford
Distribution transformers are not usually thought of as having a winter
rating. On the other hand, distributions lines definitely do. Sometimes work
on lines can only be done during the winter, because the load has to be
shifted to lines that can only handle the increased temporary load during the
winter.

There is a science and an art to sizing residential xfmrs. Generally is
depends on the square footage, number of bedrooms and type of fuel used to
condition the house.

Probably where GP is running into problem(like most electrical utilities) is
that the use of electricity per square foot keeps going up.(caused by the
increase of electrical devices in the home) So while the xfmr might have been
sized correctly when installed 20-40 years ago, it is no longer sufficient.
This causes problems.

Source: I was a distribution engineer for 7 years.

~~~
phasetransition
Thanks for the info. Day job has me using the NEC frequently, and occasionally
the NESC.

But I never thought about pole xformer sizing until this house. Our 35kVA
(summer) faceplate xformer services nine homes. Even though it browns, it
keeps on working. They've got a lot of margin, it seems

------
ars
> There are three because that is one way to change the three-phase power to
> single-phase, something I wish I understood better.

No, that's not correct.

Three transformers is for changing 3 phase medium power, to 3 phase regular
voltage (for commercial customers).

For single phase home customers, you run a single one of those phases along a
street and attach center tapped transformers to it.

The center tap means from the top to the center is 120v, and from the center
to the bottom is another 120v. This gives something called "split phase", and
is how homes in the US are wired.

This allows you to get 240v in the house if you need it by attaching to the
top and bottom of the transformer.

The center tap of the transformer is also attached to the ground, and to the
neutral power line (back to the generator). This gives what is called "zero
voltage" (voltage is always relative, there is no such thing as absolute zero
voltage - so you just have to pick something, and call it zero).

~~~
junkcollector
Going to be a bit pedantic here but you absolutely can have 0 Voltage. Voltage
is the potential energy created by a difference in charge between 2 points. If
you have a mass with sufficient free mobile charge, when you inject additional
charge into it, it will rearrange the charge within itself to cancel out in
injected charge resulting in 0 Volts of potential. This is the principal that
a ground connection works on and why you don't have voltage inside of metal
conductors, just on the surface.

~~~
smoyer
If you have any conductive bar or wire of sufficient size you can safely touch
both ends (and measure zero volts across them. If you stretch those conductors
over miles and miles of distance, it gets harder to reference the end to both
grounds at the same time. And getting a good ground can be hard. There are
numerous stories of "stray voltage" making cattle jumpy, etc.

Of course if you coil up that conductor and pass a magnet by it you're going
to get shocked ;)

------
gilbetron
My dad was an electrician for about 40 years - one story he told me when he
was training apprentices years ago was teaching them how to climb telephone
polls. You wore boots that had spikes in the side of them, but when climbing,
you had to keep your knees away from the poll so the spikes would dig in
properly. Unfortunately, when you get to the top of the pole and look down,
some people panic due to the height. And when they panic, they tend to "hug"
the poll, which causes the spikes to pull out, which causes the person to
slide down the poll which is pretty much a collection of splinters in poll
form. They called it "burning the poll".

~~~
grzm
Nit: s/poll/pole/g

~~~
gilbetron
Sigh, thanks ;)

~~~
grzm
They’re and their are my personal bugbear. I’m right there with you. :)

~~~
jsjohnst
The way I solved that one mostly is to always repeat the sentence back and
swap they’re for “they are” in my head (same for its vs it’s).

------
CaptainDecisive
I did some work for an electricity utility and they wanted to get the pole IDs
described in the article into our database, alongside the GIS data. The client
explained that getting the IDs was kinda difficult and there were several
different data sources for the various regions they provided service to. By
and by we found a guy there who knew how everything worked and promised he'd
get us the data that we needed - which he did.

But he told me an interesting story - the utility had about 50,000 power poles
in their network. But due to various historical reasons and how their assets
were digitized over the years he reckoned there were probably about 1000 of
them that were on their maps, but that didn't actually exist anymore. And
interestingly, he thought the inverse was also true; that there were perhaps
1000 poles out there that weren't on any of their maps. Big ten meter tall
poles, some probably carrying live cables - didn't know they were there.

~~~
jedberg
> that there were perhaps 1000 poles out there that weren't on any of there
> maps

I can totally see how this would happen. When I bought my house, the
power/utility lines were hanging about four feet off the ground in my
backyard. Apparently the previous owner didn't care.

I called the utility company to complain, and they sent someone out with a new
full size pole, who basically just shoved it in the ground in the corner of my
property to prop up the lines.

As far as I can tell, there are no identifying marks anywhere on the pole. No
label, no inspection, no nothing. Except a sign that says "Danger, do not put
ladder on this cable", which is on the fiber optic cable that runs along the
pole.

~~~
Dangeranger
This is common at every utility. Part of the issue is based on the fact that
the GIS systems do not align with the paper systems 100% and the paper systems
are typically regarded as the standard.

Another problem that must be considered is that utility workers, while highly
competent at their profession, are not always great with working on computers.
They generally write everything down on paper and then have one of the younger
linemen input the changes into the electronic records system.

Also utilities often have several record systems in place, some being GIS
based, and some being mobile computer based with check in with a central
database. These systems are almost never developed and worked on by the same
people, so inconsistencies abound. It's normal for the inventories to diverge,
and for updates to take weeks to propagate from one system to another.

~~~
Caveman_Coder
> "Another problem that must be considered is that utility workers, while
> highly competent at their profession, are not always great with working on
> computers."

You're absolutely correct on this point. When I was working as a transmission
system operator the older guys (all in the 50s and 60s) would complain all day
and night about the new "computer apps" that were introduced in our day to day
workflow. They all preferred the old "pen and paper" way of doing
things...Like you said, I'd be the who would end up putting the written
switching procedures into the application we used since the older guys
basically refused to learn it...

~~~
ssegraves
This is still a major problem in distribution. Some of the best workers are in
their late 50s and they are familiar with older equipment in the field that
the younger guys may have never seen.

They would much rather use pen and paper to report what they did or didn’t do,
with little appreciation for the reporting that could be done with a bit of
input on the computer.

------
jvolkman
Pole replacement is interesting and full of bureaucracy. At least here in
Seattle, the power company doesn't have authority to move communications wires
and equipment attached to poles that are being replaced. So often times
they'll cut the bottom off the old pole, move it to the side, install a new
pole, and then use seemingly whatever they've got lying around to lash the two
of them together. Owners of the other equipment eventually get around to
moving their stuff (sometimes years later), and the last one removes the pole.

Some examples: [http://archive.seattleweekly.com/news/960949-129/whats-up-
wi...](http://archive.seattleweekly.com/news/960949-129/whats-up-with-
seattles-messed-up-utility)

------
joeframbach
Old utility poles can be reused in many ways too, but they must be outdoors,
and not where it can have direct contact with people. Back in 2003 I called a
local electric company if they could donate a few used poles to be used as
beams for a bridge I was constructing for a local park. They we're happy to
oblige. You can sometimes see these poles used in retaining walls and buried
alongside hiking trails, used as water bars. I keep an eye out whenever I'm on
a trail and am sometimes surprised to see an electric pole miles from a
trailhead.

~~~
sevensor
> and not where it can have direct contact with people.

Could you expand on that? My elementary school had a playground structure made
of old utility poles. Other than getting pitch on our clothes, they didn't
seem particularly hazardous.

~~~
ranger207
They're treated with lots of preservatives. They're probably not all that
dangerous in the short term (unless you eat some of the pitch), but it's
annoying to deal with the potential long term safety. My scoutmaster worked
for the power company, and I was going to ask him if we could have a couple of
poles for my Eagle project, but after looking at what you had to do to reuse
them I decided it was simply too much of a hassle.

~~~
sevensor
Could be a lack of awareness, as this was several decades ago. We also had a
jungle gym made from pipes set in a concrete pad.

------
s_tec
Regarding three-phase power:

The electrical outlets in your home have two power-carrying prongs. The third
prong is just for safety (it connects to the ground), and should never carry
power unless something is going horribly wrong. In that case, the power should
hopefully prefer to reach the ground through that third wire than through your
human body.

Anyhow, the voltage in those two power-carrying wires is constantly switching
directions. At one moment, the left wire will be +170 volts relative to the
right wire, and then they will slowly switch places over the next 1/120 of a
second so the right wire is at +170 volts. They continue trading places,
completing a cycle every 1/60 of a second.

At some point in this cycle, the voltage difference between the two wires will
be zero, which means that no power will be flowing at that moment (power =
voltage * current). On the average, the wires will deliver the same amount of
power _as-if_ they had a constant 120 volts between them, which is why people
say that electricity in the USA runs at 120VAC. The peak-to-peak voltage is
170V, but the "RMS" average voltage is 1/√2 of that, or 120V.

Anyhow, those brief moments of time where no power is flowing are a problem
for a power company, who would like to deliver energy in a continuous stream.
So, they build their power system with three wires. Each wire reaches its
maximum voltage 1/180 of a second after the previous wire. Since the voltages
on each wire are sine waves, when one wire is at 0, the other wires are at
+√3/2 and -√3/2 of their maximum voltages. Therefore, there is no point where
the power stops. In fact, due to a mathematical quirk, the power delivery is
actually constant, even though the voltages on the three wires are constantly
changing.

Turing three-phase voltage into two phase voltage is pretty easy. Just pick
any two of the three wires and hook them into the home. The difference of any
two sine waves is just another sine wave at the same frequency, so you
automatically have single-phase power. In practice, the power company will try
to balance the load between the three pairs of wires by sending different
pairs into different houses or even neighborhoods.

Edit: As several people have pointed out, this isn't _quite_ how it works in
real life. See the comments below for details about the hot vs. neutral wire
and how both 240V and 120V are available in the home at the same time.

~~~
dnm
> the voltage in those two power-carrying wires is constantly switching
> directions

I'm not buying this (in the USA). I've been in my breaker box. For a typical
110 volt outlet, the black (hot) wire is connected to the breaker, which is
connected to one of the wires coming into the house from the street. The white
(neutral) wire is connected to the same ground bracket that the bare (ground)
wire is connected to.

240 volt connections (like my dryer and range) are taking a hot line from one
of the lines coming into the house and another hot line from the other line
coming into the house. You can see it on the bus bars in the breaker box.
That's why dual breakers are used. Adjacent breakers pull for different bus
bars.

*edit typo

~~~
s_tec
Right, that is correct. To understand how that works, you have to realize that
there is no such thing as an "absolute voltage", only the voltage difference
between two wires.

In a breaker box, one wire (white) gets tied to ground, and the other wire
(black or red) goes between +170 (relative to ground) and -170 (relative to
ground). The black and red wires are 180 degrees out of phase, so when the
black wire is at +170, the red wire is at -170. This gives a 340V peak
difference between the black and red wires, which averages to 240V. You get
your normal 120V outlet power between the hot legs and ground/neutral, and you
get your 240V dryer & water heater power between the two hot legs themselves.

So, in a normal outlet, we can safely say that one wire is "more positive"
than another, and that this flip-flops through time. When we look at voltages
relative to ground, though, one wire stays put at 0V while the other goes
between +170 and -170. It's just a question of where you put your reference
frame.

~~~
ars
This is not what you said in the other post. You are confusing people, and you
should edit it.

------
andyjohnson0
A good book on this and related subjects is _Infrastructure: The Book of
Everything for the Industrial Landscape_ by Brian Hayes. Published in 2006 so
almost certainly out of print, but probably easy enough to get on Amazon or
similar.

~~~
agwa
Thanks for the recommendation; that book looks amazing!

And there's a revised 2014 edition in print: [http://industrial-
landscape.com/#/buy](http://industrial-landscape.com/#/buy)

~~~
nkurz
Thanks to both of you. It does seem to be a great book! I've requested it
(well, the older version) from my library. Apropos this article:
[http://industrial-landscape.com/#/18](http://industrial-landscape.com/#/18)

~~~
squeed
Enjoy it! I've had this book for years. It's one of my treasured possessions.

------
femto
A bit of information: Openstreetmap includes a field for the identification
number on utility poles. A lot of people fill this field in when they do
mapping (I do). Thus OSM is quite a good reference for these numbers, and the
general topology of the electricity grid.

------
dustinmoorenet
I was looking at the transmission lines one day and was curious about why
there are always 4 wires. Basically, 3 lines carry equal voltage phased 120
degrees apart from one another. This kind of power is easily generated from 3
phase power generators at the power plant. The 4th wire is a common return for
all three wires. It is normally smaller than any single load wire because, if
the power is distributed evenly, no load is carried on it.

The second part of the system, is that, normally, no one customer will use
more than one of the three load lines. That is why most houses only have one
transformer on the pole out side their house. The power company makes sure
they balance connections evenly within a given area. If they do this properly,
the common 4th wire has no load on it.

Some buildings do use all three phases, but they would be running large
industrial machines that benefit from having that type of power.

I tried to find the Wikipedia article that covered all this, but can't seem to
locate it specifically.

~~~
toomanybeersies
Is that an American thing?

I've never seen 4 lines on a power line in New Zealand unless they're also
carrying telephone lines.

~~~
gunzel
I think New Zealand is the same as Australia with 5 wires: the 3 phases,
neutral (the central return wire) and earth. Grabbing a random location in
Auckland off Street View shows 5 wires:

[https://goo.gl/maps/wz1W73uWAiz](https://goo.gl/maps/wz1W73uWAiz)

~~~
dustinmoorenet
That just seems odd to me to have a wire for earth... carried above the earth.
I can understand having earth wires in houses made of concrete and wood since
they have to get to the earth through those materials, but what makes a common
earth ground better than just lots of many grounding points? All that wire has
got to get expensive.

~~~
JoeAltmaier
The earth is a pretty terrible conductor.

~~~
dustinmoorenet
The point of an earth ground is to dissipate the accumulation of static built
up. Ground is not connected to the power supply so there is nothing to return
to the power company. The earth is the best place for it.

------
caf
_Probably they computerized this back in the seventies, and the books are
moldering in a closet somewhere._

Oh, sweet naive summer child.

------
shmerl
I'm now spotting fiber optic cables on different poles :) They commonly use
distinguishable splice enclosures which look like this:

* [https://fiber-optic-catalog.ofsoptics.com/Asset/Closure.jpg](https://fiber-optic-catalog.ofsoptics.com/Asset/Closure.jpg)

* [https://thumbs.dreamstime.com/z/fiber-optic-enclosure-splice...](https://thumbs.dreamstime.com/z/fiber-optic-enclosure-splice-cable-storage-bracket-hanging-aerial-messenger-strand-bonded-to-wood-pole-47258472.jpg)

~~~
eptil
Your bottom picture also shows half of a snowshoe fiber slack storage
location. They are used at almost every splice so the splice can be moved to
the ground easily and placed into a splicing trailer. That fiber pictured is a
strand and lash construction where a high strength steel wire is placed and
then the fiber is basically tied to it. We have stopped using any of it in
favor of ADSS fiber which means all dielectric self supporting. We can place
it in the power space and avoid dealing with the communications space
problems.

~~~
shmerl
_> a snowshoe fiber slack storage. They are used at almost every splice so the
splice can be moved to the ground easily and placed into a splicing trailer._

Interesting, thanks for pointing out how it's called and what's the purpose of
it. I saw it around, but had no idea what it's for :)

I noticed though, that for example Optimum fiber network is using it, while
Verizon one does not.

------
ggm
In Australia we have a life extension program for hardwood poles which slides
a steel formed sock/support down the side to stabilise it for many a year more
after a hard life.

We had some issues with corrosive dog wee. Tar treatment sometimes works. Also
steel collars to keep possums off the top structure.

In Europe there are other platforms above the transform and wire complex for
bird nests. Storks, cranes all above the risky bit.

Aussie poles are made from wood which is harder than nails. Unbelievably
strong stuff which years of soaking in very nasty chemicals defends from
termites which are ubiquitous.

~~~
Dangeranger
As I understand it one of the largest concerns in AU are the wildfires
damaging circuits connecting the disparate grids. There was some conversation
about replacing some of the network poles with fire resistant poles in order
to try and avoid the high number of outages caused by fires during the dry
season.

I'd be interested to know how that project went, and if it was successful.

~~~
gunzel
Not so much bushfires damaging electrical infrastructure as electrical
infrastructure starting fires. A large portion of Victoria's worst day of
bushfire was sparked by a faulty power line and the electricity distribution
network (22kV and below) is responsible for a good portion of fire starts,
especially those lines that utilise a single wire with an earth return (SWER).
The recommendations of the Royal Commission into the Black Saturday fires in
regard to the electricity network are available at
[http://royalcommission.vic.gov.au/Commission-
Reports/Final-R...](http://royalcommission.vic.gov.au/Commission-
Reports/Final-Report/Volume-2/Chapters/Electricity-Caused-Fire.html) and
contain a whole lot of background information. Suffice to say that the
recommendation (27) of the wholesale burying of thousands of kilometres of
SWER line at the cost of billions of dollars haven't gone far.

------
ogig
>Warning: Probably at least 30% of the surmise in this article is wrong.

I like honest authors.

------
pan69
I have always wondered about utility poles, they always seem very fragile. Why
not just stick everything in the ground?

~~~
zwieback
I think it's cost, mainly. Also, in my neighborhood of older homes it would be
hard to get all the easements.

[http://www.elp.com/articles/powergrid_international/print/vo...](http://www.elp.com/articles/powergrid_international/print/volume-18/issue-2/features/underground-
vs-overhead-power-line-installation-cost-comparison-.html)

~~~
toast0
Many of the easements for above ground utilities also contain provisions for
underground utilities, so getting easements may be easier than you would
think. However, having the easement, and having it be feasible to use are two
different things. In my neighborhood, some sections have the utilities in line
with the sidewalks and there is easy access; others have the utilities behind
the homes, over many years many buildings have been built encroaching the
easement. The encroaching buildings aren't legally there, but it would be
messy to remove them to underground the utilities.

------
the_mitsuhiko
It’s interesting how such super common things can be completely different in
sifferen countries.

Over here (Austria) utility poles effectively don’t exist. Everything is below
ground and all households get three phases.

------
etimberg
Sort of related, but if anyone finds this topic interesting and is looking for
software positions related to power systems engineering the startup I work for
is hiring. We create 3 phase unbalanced distribution system simulation and
optimization software to enable PV & battery integration by utilities.

We currently have a number of open positions:
[https://www.opusonesolutions.com/careers/#navigation-
positio...](https://www.opusonesolutions.com/careers/#navigation-positions)

~~~
Caveman_Coder
What exactly does the company do and how do they do it? It is kind of unclear
and the "Our Mission" section of the website is one of those generic PR
sentences that doesn't actually explain anything about the business...

------
spunkles
"The poles around here all carry ID numbers, and I imagine that back at the
electric company there are giant books listing, for each pole ID number, where
the pole is. Probably they computerized this back in the seventies, and the
books are moldering in a closet somewhere."

Pretty much... I did data entry for 10 weeks in 2006 putting scanned records
of wayleaves into a GIS system for Central Networks (a UK based electricity
infrastructure company). Basically they had a record of every single pole,
pylon etc, and a record of the legal agreement to access the pole for
maintenance (a huge number are on private land, like in a farmer's field or
your back garden or an office parking lot). All these records had been input
into a GIS system by taking the (very) rough map reference and the pole
number, putting that into structured fields, andthen everything else was just
scanned documents - my work was part of the upgrading of that (which had been
done years before) to completely structured data and a very accurate placement
on the map. For legal reasons a lot of the original documents are still kept
somewhere. Typically these documents outline both the placement, access
arrangement and any payments (which may be ongoing) made to ensure access.

------
losteverything
The best example in my stats class on why sampling was used: working for the
phone company he had to determine if poles were rotting. Practically speaking
he could not use a random sample: he sent a pole climber to an area and while
there, climb a few or several in the area. It would not be practical to climb
one here, another 3 miles away, etc..

------
oasisbob
I've always liked the symbols used to indicate pole defects to climbers, a
white arrow on a red field:

[https://www.lemproductsinc.com/utilities/utility-pole-
markin...](https://www.lemproductsinc.com/utilities/utility-pole-marking-
tags-2/defective-pole-tags/)

[http://www.techproducts.com/new/op/markers&tags/everlast_pha...](http://www.techproducts.com/new/op/markers&tags/everlast_phase.asp)

------
Slansitartop
> The cans are full of mineral oil, or sometimes vegetable oil! (Why are they
> full of oil? I don't know; I guess for insulation. But I could probably find
> out.)

I think the oil's for cooling, actually.

~~~
Neil44
I thought it was interesting so I looked it up.

[https://en.m.wikipedia.org/wiki/Transformer_oil](https://en.m.wikipedia.org/wiki/Transformer_oil)

~~~
Slansitartop
> Its functions are to insulate, suppress corona discharge and arcing, and to
> serve as a coolant.

------
vilda
Transformer oil is there primary for cooling and secondary for corrosion
resistance. When you see transformer burning, it's the oil inside. Larger
transformers cycle oil through pipes visible outside.

In the Czech Republic (or at least in some parts) pole numbers and their
positions are shared with emergency services. If you are disoriented, reading
the number identifies your exact position. Works for railway crossings as
well.

Update: typos

------
EADGBE
> As I discussed recently, some of those poles are a hundred years old, and
> the style of the ID tags has changed over that time:

Truly amazing craftsmanship, right there. Infrastructure that's backwards -and
forwards - compatible. Unhackable, able to run for decades or centuries at a
time.

I yearn for the analog.

------
_Codemonkeyism
As a German I'm always amazed by the ugliness of those power and telephone
poles in other countries.

There is talk here to also build phone lines with poles in the future as it is
cheaper, hope this never happens.

~~~
kbart
Phone lines? Are line phones still so popular in Germany that it even requires
network expansion? In my country copper lines are basically left to rot as
line phones are being replaced by cell/IP phones rapidly. In some cases people
living in remote areas were issued free cell phones, because it was cheaper
than repairing old copper lines.

~~~
_Codemonkeyism
Fiber optic lines.

------
methodin
That was the most interesting thing I've read in a while. The things you take
for granted are designed well enough that you forget they are there.

------
danschumann
Is that the same image they used in the article "Japan's anime is obsessed
with power lines" ?

------
ssegraves
Work with a number of utilities in distribution. Happy to answer any
questions.

------
jhoechtl
What wood are the poles made out to last for so long?

------
rothrock
[https://en.wikipedia.org/wiki/Transformer_oil](https://en.wikipedia.org/wiki/Transformer_oil)
c'mon really? you didn't even look?

What is this? You're "interested in utility infrastructure" !?

7000 Volt lightning?

most household uses ... they want single-phase power!? In 1910, maybe.

~~~
PhantomGremlin
_most household uses ... they want single-phase power!? In 1910, maybe._

Huh? In the USA all residential is single-phase. Although there's a center
tapped transformer involved, which is what gets you both 120 V and 240 V from
one phase. This arrangement is called "split-phase":
[https://en.wikipedia.org/wiki/Split-
phase_electric_power#Nor...](https://en.wikipedia.org/wiki/Split-
phase_electric_power#North_America)

Name one "household use" in the USA (which is where the author lives) that
doesn't use single-phase power? I'll give you a head start, I once lived in an
apartment building that used 120V/208V for electric hot water heaters. But
offhand I can't think of anything else.

~~~
M_Bakhtiari
It is strange though, that residential three phase is so uncommon there,
especially when the single phase voltage is only 110, further sacrificing
efficiency for high power applications.

~~~
ars
High power applications use both sides of the split phase, for 240v.

