Seems to me a big vulnerability in modern life is the power grid. Bad winds, a thunderstorm, or a blizzard knock out power for thousands, sometimes for many days. Which is particularly bad when it’s very hot or very cold outside.
I know a lot of houses have underground power lines, but around here the main lines are always up on poles. Shouldn’t the main lines be buried, or is there a reason not to? They could be marked just like underground natural gas lines are, that would be less of an eyesore than all the poles and cables.
Also if pure electric vehicles catch on, it will be a real hassle not being able to plug in your car for several days.
When they were widening a local main drag around here, the Town Council had the idea of putting the wires underground. Once they heard the price tag, they gave up on the idea – it was a substantial percentage of the entire project, something like a million dollars a mile (15 years ago).
It’s also somewhat harder to service if you have to dig to get to a broke line.
Buried power lines have huge up-front costs, especially in areas already developed. People generally do not realize how much infrastructure is already in the public rights-of-way (i.e. roads). You’ve got water, sewer, drainage, gas, along with the increasing demand for buried electric, telephone, cable, and fiber-optic lines. There is only so much room in the road.
Overhead lines have much lower up-front costs, but you have to worry about tree-trimming and repairing downed lines, which leads to higher maintenance costs, but these are spread out over time. Also, it is easier to upgrade overhead lines.
All-in-all, however, buried lines are generally preferred. Particularly in new developments, when the roads are first being constructed, it is not as expensive to lay in the needed conduits. (It’s far more expensive to excavate and repair a existing road.) For this reason, in new developments, I almost always see buried utilities in lieu of overhead.
For cross-country high-voltage lines, however, the dynamic changes again. It is almost always prohibitively expensive to install buried high-voltage lines, as opposed to widely spaced towers.
In my area, we have Rule 20A, supported by the California Public Utilities Commission. It gets some of the existing lines buried every year. And in Stockton, new developments are required to bury the electrical and phone wires. So we’re chipping at it. It’s going slowly. That 30 miles is spread over all of PG&E’s service area.
As everyone else has said, it’s expensive and it makes expansion more expensive. When Stockton added a sports arena and hotel near the waterfront, PG&E started digging up downtown streets. They had to add more lines and enlarge a number of vaults. So, in addition to the cost, any expansion to service affects traffic.
Potholes. Polluting fuels. Crime prevention. Drug treatment. There are a lot of things that government and industry do that should prove beyond much doubt that they don’t think too much about “the long run.”
It may be a worthwhile investment in the long run, but in the short run, it’s a killer.
According to the article, it would cost 27 billion for my local electric company to bury all its overhead lines. In 2006, the entire electric company had revenues (not profits, total revenues) of 6.8 billion.
Putting it another way, if my local power company continues to charge its customers full rates, but spends on *nothing *except burying power lines, it will take four years. If they want to spend only their net income (that means no dividends for stockholders) they’d have to dedicate all their profits to it for the next 45 years or so.
Here we go. Above Ground Power Lines from April of this year. In the second post, **Exapno Mapcase **links to two older threads regarding the same question.
It’s expensive to dig into earth to bury lines, but it’s REALLY expensive to dig into rock if you have to. In my area, there is very little soil in many places, and even though the cable company did a geological survey before deciding to bury, they were sorry afterwards and the job took a lot longer than they expected. Surely hi-voltage lines would have to be buried even deeper than fiber optics for safety reasons.
And then there’s always the farmer who starts digging without contact Digger’s Hotline first, and disconnects 27,000 phone lines when he severs the fiber cable. Imagine what would happen if he ran into a shallow, live power line. More spectactular, I’m sure.
True, but they bury natural gas lines, along with yellow poles regularly spaced above-ground warning of the gas line. Unsightly maybe, but not as bad looking as overhead power lines.
No, they don’t although, yes, they usually do. There are above-ground natural gas pipelines which run on pylons, but they are not common, for safety reasons. The lines themselves are perfectly safe; even lightning isn’t generally an issue unless the pipe is leaking–the metal walls simply conduct the bolt straight to ground through the pylons. The real problem is they’re vulnerable to sabotage and vandalism, as well as vehicular accidents.
Overhead power lines are usually bare copper. This means they are completely surrounded by air for cooling. Electrical current flow creates heat (and heat slightly increases resistance). If you were to put the power lines underground, you’d have to insulate them, and the insulation will trap heat. You then have to de-rate the capacity of the cables to allow for this decrease in heat dissipation. The same size cable can now carry less power, or we have to use more copper, bigger cables, to do the same job as the overhead lines.
If the cables are laying together in a duct, then that also increases the heat build up and the necessary de-rating. If they’re on their own, they’re still going to get warmer than they would up in the air. So aside from from the expense of digging and burying, you pay more for the insulated cable, and have to use bigger cable for the same capacity.
It’s kind of similar for subways. NYC could never have gotten as large as it did without the subways. It wouldn’t be the business center it is. It was lucky they put the subways in when they could
Chicago was late in the 1940s putting in their subways and while the subways are OK, it’s not close to as good as NYC’s subway.
And today most cities would kill for public trans like Chicago or NYC, but the cost of going underground is way too much. Even though underground is much more efficent (look when it snows) and people are able to move faster than buses in traffic.