While I was in Europe last month I met a man who, upon learning I was from Atlanta, commented that he’d visited my hometown and was amazed that we still have above-ground power lines on utility poles.
I’d never given it a moment’s thought before; I guess I don’t notice the lines when I’m home, and then don’t notice their absence in other places.
But is it true that most American and European cities of Atlanta’s size and age now have their power lines above ground (I imagine we don’t because our city government and local power utility are corrupt and inefficient, but I want to keep this in GQ)?
Near cities in the Netherlands, power lines only appear above ground in the vicinity of power plants and power stations. Between cities, above-ground power lines do appear. But within municipalities, small or big, I haven’t seen them above ground for at least 20 years (a small town near where I was born used to have them, but they vanished in the late 70’s - below ground, I suppose).
I can’t speak for all European cities, as this is a thing one doesn’t really focus on while visiting as a tourist. But I think the description above fits most Northwestern Euopean cities. It’s quite possible that Southern Europe is a little less advanced in this regard.
A lot of the reason is cost. The US is quite a large place, with many lightly-populated areas that can be a ways away from main transformers/switchyards. I think most Europeans really don’t have a clear idea of this until they come over and drive around for a few days. And at the time much of the electrification of the US was done, we were a much, much less population-dense country than we are now.
Much new construction and replacement is being done underground, but I think aboveground power lines will be the norm for the US for many decades to come. It just costs a lot to replace them. Also, ironically, many non-technical people seem to have an idea that underground power lines are much less safe than aboveground ones - thinking they are literally just below their feet.
Speaking from a medium-sized Rust Belt city in the American Midwest, yes, I think that nowadays the new subdivisions going in make arrangements to have most of it buried. You don’t notice it unless you’re looking for it (the lack of telephone poles and power lines, I mean).
And I have the impression that new buildings going up in the downtown business district (what’s left of it :rolleyes: ) frequently have most of it buried, too.
Yeah, Atlanta’s power lines are an unsightly mess. Are there any moves afoot in any American cities to replace existing above-ground power lines with underground lines? I would love to see that happen here.
Underground electrical wires are not better visually, but they are also more realiable. After all when was the last time you heard of a drunk driver or the wind knocking over some underground power lines. Many areas that are now above ground are in the process of putting their lines underground. This depends a lot on the city and the state regulatory agencies.
Anthracite, your point about the cost of replacement is well-taken, but the Eurotrash guy I spoke to travels in the U.S. frequently, and was of the impression that Atlanta unusually still has mostly aboveground power lines.
Was he simply mistaken? Or are there whole regions of the country (the West, perhaps, where the cities are newer) where the lines have been put underground by now?
In addition to being less of an eyesore, do underground lines work better? I would assume so, since they’re not vulnerable to inclement weather or falling tree limbs.
Sometimes I feel like my city’s such a podunk. I was inspired to write this thread partly by the thunderstorms we’ve been having this week. Whenever it rains, it seems, half the traffic signals go on the blink (literally).
A bit of a cross-post I guess. I think that underground wiring is also more efficiency, especially in hot areas. The line losses on electrical wires increases as it gets hotter (i.e. the amount of electricity that is literally lost as it is transported on the wire from point A to B). By putting wires underground, out of the sun, you are of course minimizing this effect and therefore increasing the efficiency.
So by burying the cables, wouldn’t this protect them from the cold weather and thus decrease their efficiency during the winter, relative to exposed cables?
I’d always assumed that above ground cables were preferable in areas where hot summrs and cold winters predominate, facilitating their repairs when necessary, but that doesn’t seem so clear cut now.
I was a little quick with my last post. Underground cables do tend to be more efficient in delivering electricity, but it has more to do with the fact that they tend to be bigger. With underground distribution and transmission it is harder and probably more expensive to repair, but it tends to have far fewer needed repairs. There are a lot of factors that go into whether or not to go underground, but the aesthetic appeal is usually the most predominate. In Southern Califonria any new wiring must be underground unless there is a very compelling reason for it not to be.
My unscientific impression, having travelled pretty extensively throughout the US for utility-oriented biz, is that the vast, vast majority of cities and towns feature overhead lines. I would certainly not call Atlanta’s situation “unusual” at all. I would say places that have them buried are much more unusual, IMO.
Also - the West may be newer, but it’s much more spread out too. I mean hell - in Utah, you can find aboveground residential natural gas lines that run for dozens of miles, for crying out loud! I think the only places where I really see a concerted effort to put lines underground is in new subdivisions/developments, like DDG said.
My impression of the Toronto area:
[ul]
[li]Rural areas are all aboveground.[/li][li] Major grid connections and high-voltage lines are aboveground.[/li][li]Most newly-onstructed suburban areas include aboveground trunk lines, but all the new local stuff in each subdivision is underground.[/li][li]In the older parts of the city though–and by ‘older’ I mean most places built before the suburban boom after the Second World War (say 1955 and after)–the distribution is aboveground to the individual buildings.[/li][li]In the central city, there are underground feeders and transformers for the Really Big Buildings.[/li][/ul]
Another thing to keep in mind about burying power lines is the potential danger. If you dig and break, say, a CATV conductor, it’s merely an inconvenience. If you dig and break a power conductor, ouch!. All conductors (even fiberoptic) will be pulled through conduit, typically PVC, placed in the ground. High power electric, as well as, trunkline copper and fiber for the telco/CATV, should always be buried in concrete-encased conduit. Depth of bury is dependent on the municipality or owner of the easement/right of way, but power is deepest (for obvious safety reasons), probably about six feet, even more at rail crossings. This costs serious money to conform to NESC codes. I suspect it costs as much as 25 to 75 times as much to install a mile of underground plant as it does aerial plant.
My company recently designed a concrete-encased duct bank for a CATV company with 14 individual ducts. The length of the run was just over 2 miles; not very long at all. It crossed three sity streets and one set of railroad tracks. This job was awarded to the contractor for $1.7 million. See? Serious money when you start talking about burying thousands of miles.
One more thing to consider is the size and quantity of storm sewers, sanitary sewers, waterlines and gas pipes already down there. In many places there is already too much of that shit in place to attempt to bury your power and communication conductors.
Yup, most European cities are packed much more densely and so it is economically more feasible to bury cables. Here in a residential area of DC I can look out my window and see the 3 wires of 110 volt supply but, on the same posts you have cable (TV) just below them and the hight voltage wire above. When tree limbs fall on this arrangement it makes for nice sparks. I do not think the code would allow this in Europe but,again, the situation is different.
In downtown DC the wires are buried and we often see them in the news as well. Transformers blowing up manhole covers high into the air, underground fires… it seems it is happeneing constantly. In Europe, as they use higher voltage, they probably need to have much safer installations… I have never heard of this happening so frequently in Europe.
BTW, a bare cable overhead would always be cooler and can carry more amps than the same cable buried. Forget about the sun. Electrical insulation in thermal insulation as well. A bare overhead wire can always carry more amps. Just look at the code.
From an urbanised no-European, non-American location where we have had underground cabling for some time here and I have never heard of a transformer (most of which are above ground) that has blown up, they can short occasionally in electrical storms, however the underground wires do tend to appear more reliable than the above ground variety where, (this could of course be due to the improved technology available when they were installed).
i work for a utility and the reason that conductors are overhead and not underground is price. putting lines underground costs so much more than putting them overhead.