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Why Aren't Powergrids Underground? 556

jonging asks: "It is common knowledge that an underground power grid is less susceptible to the effect of a large thunderstorm. The American Transmission Company cites numerous reasons why it (and other power companies I assume) do not bury their transmission lines underground (e.g. environmental concerns, cost of installation and repair, etc.). Exactly how detrimental are underground transmission lines to the environment? Wouldn't the time spent without a power outage generate more than enough revenue to offset initial costs? Aren't the need for repairs in cities with successful underground power grids rare?" The linked article goes into extensive detail about the disadvantages in initial costs of putting in underground lines, but doesn't go into any detail about the maintenance costs of either option. With storms getting worse and worse (Maryland, DC and Northern Virginia have weathered torrential downfalls this week), might underground lines prove more resistant to storm-related power outages?
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Why Aren't Powergrids Underground?

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  • It costs money? (Score:4, Informative)

    by NotQuiteReal ( 608241 ) on Tuesday June 27, 2006 @08:45PM (#15617429) Journal
    That is all I have to say.

    Sure, it would be nice to put it underground, but it costs more that way...

    • Re:It costs money? (Score:2, Interesting)

      by Anonymous Coward
      I would actually like to see some figures to back that up. Sure running one powerline down a street costs more than running the same powerline underneath the street.

      What about in the long term, though? Rather than putting a powerline underground, put in a conduit. Workers can work down there without the need for expensive cherry pickers, having to haul equipment up to polls, without affecting traffic. Work would probably be easier and more efficient. Need to run fiber optic/cable/whatever? No problem - the
      • Re:It costs money? (Score:5, Informative)

        by tomhudson ( 43916 ) <barbara.hudson@b ... m ['son' in gap]> on Tuesday June 27, 2006 @09:17PM (#15617547) Journal

        Long term it still costs more.

        Its a lot harder to maintain buried conduit. Plus, there's the problems of accumulated gases in any piping you lay down, plus drainage, plus trash/dirt/crap accumulation at the manholes.

        Look what happens when buried conduit deteriorates - the resulting fire is nasty because its more concentrated than in the open air.

        • Re:It costs money? (Score:5, Interesting)

          by caseydk ( 203763 ) on Wednesday June 28, 2006 @01:33AM (#15618732) Homepage Journal
          Part of the thing *not* discussed here is that there are huge amounts of the power distro system in DC which *is* underground. The problem that they've run into - and I've had conversations with the people maintaining them - is that maintenance is a nightmare.

          Getting to the underground lines is a bear and then making any changes is even worse. In most scenarios, they actually wait for the equipment to fail (eg. ignite and/or blow up) before they can do anything because the alternative is that they take down multiple city blocks for hours...
          • Re:It costs money? (Score:3, Informative)

            by b0s0z0ku ( 752509 )
            Part of the thing *not* discussed here is that there are huge amounts of the power distro system in DC which *is* underground.

            AFAIK, all of it, except for substations and the electrification of the Northeast Corridor rail line coming in from Baltimore. There's some old law prohibiting basically any overhead wires, and it's strictly applied - even the new trolley line in DC will have to use third rail (AFAIK, electrified only when a tram is passing on a given section) because of it.

            -b.

          • The other item *NOT* discussed in depth is the thermal consequences of going underground. The ground has a limited capacity for pulling heat away from lines as they heat up from the power running through them. An above ground installation with as little as 3.3ft/sec (1m/sec) airflow at a 90 degree angle can provide significant cooling allowing the power company to run even more power through the lines. In the hot summer months typical in the US, this can mean the difference between brown/black outs and b
            • Re:It costs money? (Score:3, Informative)

              by AB3A ( 192265 )
              Mod parent up, please. Overhead power lines are much more tolerant of higher loads. There is also the issue of insulation breakdown underground. Furthermore, burying power lines means you need to keep extremely detailed records for a very long time.

              As someone who works in a water utility (where pipes are laid in the ground and expected to stay there for the next 100 to 150 years) let me be the first to point out the hazards of trying to keep such records for such a long period of time. Standards change.
          • ...NOT Distribution lines. There is a HUGE difference.

            Part of the thing *not* discussed here is that there are huge amounts of the power distro system in DC which *is* underground

            That is because the *distribution* systems are not even part of this discussion. Transmission lines present a whole different set of challenges. Firstly, they are longer, second they are MUCH higher voltage--hundreds of kV, and third a transmission line serves a much larger area than distribution lines.

            In most scenarios, they ac
        • "Long term it still costs more."

          I'd say that's debatable. My power bills were more in Denver than an hour north. In Fort Collins, Colorado, a study found that the quality of life was higher because the skyline lacked the unsightly transmission lines. I can say, being here, that it is a benefit to creating an overall, less-clustered atmosphere (I like to see the mountains when the pollution isn't in the way). The plan to bury lines was started before the town started growing, so various in
        • Re:It costs money? (Score:4, Interesting)

          by hey! ( 33014 ) on Wednesday June 28, 2006 @09:57AM (#15620599) Homepage Journal
          Long term it still costs more.

          Even if you add up the costs over, say, twenty years and find you've spent more under the above ground scenario, it may still cost more if you include "opportunity costs". Suppose I could spent $25M to put in an above ground transmission system in an area, and pay out $25M over twenty years, vs. spending $50M for underground and for sake of argument 0 for maintenance of the same period. It's not a wash, because in the second scenario you have $25M in your pocket you can invest; in the first scenario you miss out on the interest.

          There's an even simpler explanation as well. There is no market for power distribution. If you are dissatisfied by the reliability of your electrical grid, you cannot switch to a competitor's grid. The owners of the grid will charge you the cost of running the grid plus as much as they can get away with over that. They have no incentive to take their money and, effectively, bury it in the ground to give you another sigma of reliability. All they have to do is get you enough power so they can charge you, and not get nationalized by a furious public. Which might not be a bad thing, if you compare the interstate highway system to the electrical grid.

          The most amazing thing about the electrical grid is that it works at all. And indeed most of the time it works well when compared to, say, Iraq. But although it works in routine cases, it does not work in even moderately exceptional cases, such as peak demand for air conditioning. And it certainly does not work to address problems like the California power crisis of several years ago.

          Looking forward two to three decades, the electrical grid is probably the single most important piece of infrastucture to improve if the US is to remain a viable economic power. As oil production drops, and world demand rises, prices will rise. The grid is critical in enabling us to respond by bringing more diverse energy sources on line. The roblem is that many of these sources: wind, solar, tidal, geothermal etc. aren't located where the power must be consumed. And others, such as nuclear, are not politically practical to place neir population centers. And you can't build them overnight. Although we can see a trend of increasing oil prices into the future, when it comes it probably won't be smooth upward ratcheting off prices. It will probably come as a series of shocks (if it hasn't started already).

        • Re:It costs money? (Score:4, Informative)

          by mothlos ( 832302 ) on Wednesday June 28, 2006 @12:12PM (#15621724)
          I can personally attest to the problems of buried electrical cable. I am a dispatcher for a local power company. About 3/4 of our grid is above ground with the rest earth buried (not tunnel buried as in some cities). Buried cables account for fully half of our line failures. The most common issues are the result of earth shifting and water seepage. Repair of underground cable requires extra equipment and manpower to locate and excavate to fix problems. Also, there is a danger of damaging underground cables and pipes maintained by other utilities. Utilities spend a lot of money locating their underground infrastructure for each other.
      • Re:It costs money? (Score:2, Informative)

        by Sam Ritchie ( 842532 )

        I would actually like to see some figures to back that up.

        I don't have any hard numbers, but I seem to recall a figure of AUD 1 million/km being bandied about for burying high-tension lines in Perth (Western Australia). Most local councils here are already in the process of putting the residential supply underground, but the higher voltage distribution network is just too expensive. Interestingly, one of the main reasons for underground power here (besides 'suburban beautification') is to prevent poletop f

        • Re:It costs money? (Score:3, Informative)

          by kv9 ( 697238 )

          I doubt you could run cable in a conduit next to high voltage power?

          you could run fiber.

      • Re:It costs money? (Score:4, Informative)

        by ray-auch ( 454705 ) on Wednesday June 28, 2006 @05:13AM (#15619457)
        I would actually like to see some figures to back that up.

        http://www.highland.gov.uk/NR/rdonlyres/CBDD84F3-3 326-4DB9-AAA1-44537AE9B885/0/text.pdf [highland.gov.uk]

        Has a lot of good info on underground vs. overhead for proposed new powergrid in Scotland.

        Estimates of lifetime cost ratios (table 8 at the end of the document) are between 6.9 - 10.2 for traditional fluid-filled cable and still 4.9 - 7.8 for newer (and arguably less proven) XLPE insulation technology.

        Also, this is recent tech which you would use to build your grid _now_ - go back a couple of decades and the difference was much larger. At Dinorwig - http://en.wikipedia.org/wiki/Dinorwig_power_statio n [wikipedia.org] - they had to run the first few miles of cable underground because of national-park restrictions, and there you're looking at water-cooled cable requiring acutal cooling stations (size of small house) every couple of miles. While it's very impressive to see an entire power station underground, with no visible power lines, it was definitely not cheap to do it that way.

        Bottom line is that the overhead option is using a few feet of air to get its insulation for free, and it's always tough to compete with free.

      • Re:It costs money? (Score:4, Informative)

        by the_xaqster ( 877576 ) on Wednesday June 28, 2006 @07:04AM (#15619703) Homepage Journal
        One of the main problems with underground cables is locating faults. Most faults are caused by water seeping into the cable via a damaged insulator. When enough water has seeped in, the cable shorts and blows the breaker. Unfortunatly, this also dries the cable out nicely, which means that testing for the fault becomes a problem. The best method for locating these faults is to switch bits of cable in and out, and narrow down which section it is, then dig it up.

        And how do the insulators get damaged? One way that happens more than most people would admit is it gets clipped by someone digging up something else. Say you are digging up the gas pipe in the street. If you just nick the electricity cables insulation, would you tell your boss so he can get the electric company out to replace the cable, delaying your work by hours, or are you just going to throw some dirt over it, so no-one will be able to tell?

        I have worked for 2 Electric companies, so I know a little about this.
    • Re:It costs money? (Score:5, Insightful)

      by Pharmboy ( 216950 ) on Tuesday June 27, 2006 @09:07PM (#15617511) Journal
      Cost is about TCO, not just initial. It depends on how far out you extend your costs whether it would be worthwhile to the power companies or not. This, I have no idea.

      example: We get damage in large item truck shipments. Averaged over ALL our shipments, it costs about $20 per shipment. We spent $5 per shipment to reduce it to an average of $10 per shipment (half the damage). Our net gain is $5 per shipment, plus less hassles with damage.

      For about $40 per shipment, we could get almost NO damage, but it would not meet the TCO compared to just spending the extra $5. The goal isn't to stop ALL damage, it is the lowest average cost for all shipments. They are no different.

      So there will be SOME areas where underground meets the TCO spread over, say, 10 years. Some won't. They key is having the guts to sacrifice short term profits for long term gains, which is tough if the CEO has stock options that expire in 3 years.
      • which is tough if the CEO has stock options that expire in 3 years.
        This is a classic misunderstanding of stock price. If the company opts for burried cable representing a lower TCO, this will be reflected immediatly in the market price, not in 10 years. Thus a CEO could very well care about 10, 20 years profit with 3 year to maturity stock options. Although he would have to convince the market that his choice indeed represents a long term smaller TC0, and it's in the investors and speculators best interes
        • No, it isn't. Its only immediately shown in stock price IF investors know enough to correctly calculate that AND they plan on holding the stock. ALmost no investor is- most people invest for the short term. They hold stock less than a year. Due to that, they don't care about long term viability of the company, they care about immediate profits. Hence something that costs more now and saves money over time is *not* reflected in a better price, it reduces share price because it shows reduced profits now
          • Re:It costs money? (Score:4, Insightful)

            by TopShelf ( 92521 ) on Tuesday June 27, 2006 @10:29PM (#15617893) Homepage Journal
            Its only immediately shown in stock price IF investors know enough to correctly calculate that AND they plan on holding the stock. ALmost no investor is- most people invest for the short term. They hold stock less than a year. Due to that, they don't care about long term viability of the company, they care about immediate profits.

            You may be thinking of swing or day traders, but the majority of stocks are held by institutions like university endowments, investment banks, pension plans, and mutual funds, which hire full-time analysts to make just such evaluations, and are concerned about long-term valuation.

            The company management also has a vested interest in getting the word out about such cost-cutting investments, as a rise in the share price enhances their position in the capital markets.
            • Re:It costs money? (Score:3, Insightful)

              by blakestah ( 91866 )
              These arguments are ALL irrelevant.

              Under de-regulation, if powerlines go down, the power companies contract an emergency service repair, and charge it to their customers on the next bill.

              However, power companies do have to pay out of their pockets for prophylactic tree service. So they stopped doing that, and their quarterly earnings improved dramatically.

              This is de-regulation!

              If powerlines are above ground, but tree service is kept up regularly, then power doesn't go down in storms.
      • Re:It costs money? (Score:5, Insightful)

        by MrNougat ( 927651 ) <ckratsch@noSPAm.gmail.com> on Tuesday June 27, 2006 @10:48PM (#15617984)
        Cost is about TCO, not just initial.

        The above statement is true. However, the decision to spend less money on the front end and more on the back end has nothing to do with the aforementioned truth.

        What matters is profit today. Spend as little money as possible today while taking in as much revenue as possible today. This makes the stock price go up today, which makes your options (someone else mentioned these) go up today, and the Board of Directors happy today.

        Do not concern yourself with trivialities like "tomorrow" or "TCO" or "long-term survivability." By the time any of that comes around, you'll have jumped (or been pushed) to another company that you can squeeze the same way. If you just so happen to still be around tomorrow, blame it on the office staff for using too many paperclips, and stop subsudizing employees' soft drinks.

        Once you understand that business leaders are not running businesses for the long term, or even the medium term, it's very easy to understand the (il)logic of their actions. The company exists to be soaked by execs until it dies.

        (Here, let me post my own reply: "Bitter much?")
        • by dbIII ( 701233 ) on Tuesday June 27, 2006 @11:52PM (#15618268)
          There can be a lot of water in the ground - so you get corrosion, you get water leaking in and electricity arcing and melting the cable, you get land movement as amounts of water change which can break the cable. Once you have a break it would be hard to find it - unless it is caused by the natural enemy of all underground cables - the backhoe.

          Out in the air the water drips off and broken cables are easier to get to.

          The company exists to be soaked by execs until it dies.
          Companies like this rarely ever build infrastructure unless they can get an enormous government grant for it they can milk mercilessly while providing something that doesn't work or barely works - so are unlikely to be involved anyway.
      • Re:It costs money? (Score:5, Informative)

        by Technician ( 215283 ) on Wednesday June 28, 2006 @12:47AM (#15618535)
        There is a big cost diffrence if putting in a subdivision and burying the 7200 volt line into the subdivision transformers and burying a 500,000 transmission line. Safety is also a concern. Which line would you rather hit with a backhoe?

        On a high tension line, the capacitance per foot is much higher for a buried line than for an overhead line. For long distance feeding this capacitive load adds greatly to the power loss in the line. Burried is OK in New York City, but forget it for the grid. There are too many losses. Putting the 2 top grounded lines above the high tension lines have greatly reduced lightning strikes to the power conductors and their resulting outages from damaged insulators and substation equipment.

        Disclaimer.. My father was a substation operator for Bonniville Power Administration. I've seen the MegaVar meters on some long lines.
        • Re:It costs money? (Score:3, Informative)

          by amorsen ( 7485 )
          On a high tension line, the capacitance per foot is much higher for a buried line than for an overhead line. For long distance feeding this capacitive load adds greatly to the power loss in the line.

          Go DC and forget about capacitance. That's what seems to be done for 150kV and up around here.
          • Re:It costs money? (Score:3, Interesting)

            by jeffstar ( 134407 )
            DC Lines are really cool but damn it must costs a lot to procure the 500 MVA rectifier / inverter set up. I think having to buy an inverter is a major black eye for solar power as well (unless you have DC loads).
    • How's about designing roads and sidewalks with utilities in mind in the first place. Bolt down slabs which can be lifted to lay cables and pipes underneath instead of digging up roads continuously bringing traffic to a halt.

       
    • Re:It costs money? (Score:3, Insightful)

      by catwh0re ( 540371 )
      It couldn't be too hard, most areas in my state have underground power, following this, there are currently plans to bury the rest of the overhead cables. The cost argument is a joke in itself, plumbing & gas both run underground and it's far more difficult to maintain a rigid pipe often made from aged materials, in constrast to power which is a bundle of cables that can be flexed as required.
  • DC (Score:5, Interesting)

    by Southpaw018 ( 793465 ) * on Tuesday June 27, 2006 @08:46PM (#15617431) Journal
    Though I'm not addressing TFA directly, let me comment on the DC thing. Yes. We have been utterly hammerered unto oblivion with rain in the last 5 days. But even at that, the power grid in DC is remarkably stable.

    My office, which is about 3 blocks from the White House, has never had a major event that would have an effect on our network. In about 10 months of running monitoring 24/7 on our UPS, I've never seen a major "power event" (outage, surge, something else big). I've never seen a big spike or dip. Hell, I've barely seen any variation at all in the signal.
    Perhaps it's a function of living in the big city. Perhaps it really is the fact that I'm on the same power grid as the White House. Perhaps it's just a coincidence and some really nice wiring, and me with a little too much tinfoil in my hat. Regardless, I think something is special about the power grids in the DC area.
    • by OECD ( 639690 )

      My office, which is about 3 blocks from the White House, has never had a major event that would have an effect on our network

      Coincidence?

    • You prove the point (Score:5, Informative)

      by PizzaFace ( 593587 ) on Tuesday June 27, 2006 @09:13PM (#15617529)
      Downtown Washington rarely has power outages because the power lines are underground.
      • Why this is modded +5 informative shows how bad the average person's logic is. Unless you pegged my sarcasm meter (which is possible) it seems more plausible that keeping the nations government stably powered is a more significant factor than the placement of the lines.

        Power has gone out at least once a year for the past five years to my (Downtown San Francisco) neighborhood. Due to underground power lines. A couple months ago an underground substation exploded and burned the hell out of a woman walking
      • FWIW, I live in rural Maryland. We have aboveground lines here and we've had similar heavy rain and flooding in nearby areas. Our power hasn't so much as blipped. The UPS hasn't even beeped to signal an under- or over-voltage condition. I'm more worried about brownouts later this summer than storm-related outages.

        In fact, it's only gone out, fairly briefly, once or twice in the four years I've lived here. In that same timeframe the underground fiber at work, a few miles away, has been severed twice by const
    • Re:DC (Score:5, Funny)

      by Minwee ( 522556 ) <dcr@neverwhen.org> on Tuesday June 27, 2006 @09:34PM (#15617611) Homepage

      "In about 10 months of running monitoring 24/7 on our UPS, I've never seen a major "power event" (outage, surge, something else big)"

      If William of Ockham were here he would point out the obvious conclusion: The monitoring on your UPS doesn't work.

    • Re:DC (Score:5, Insightful)

      by StikyPad ( 445176 ) on Tuesday June 27, 2006 @10:27PM (#15617878) Homepage
      I'd bet money to marshmallows that you're not on the same grid as the White House.

      But yeah, there are 1 or 2 other important buildings in DC, so keeping them powered is probably just a bit of a priority, even though most of them probably have generators. The DC area seemed to have the most stable power of anywhere I've lived, going out only occasionally during freezing rain/ice storms, and never for more than a few hours.

      The place I live now.. let's just say the clock on my microwave is rarely accurate for more than 48 hours straight. They're working on putting power lines underground in the "near future," but I'm taking it upon myself to get some solar panels, an inverter, and a nice bank of batteries. Even if they ever stabilize the grid, I'll still save a few bucks on my power bill.
  • because (Score:5, Insightful)

    by MrSquirrel ( 976630 ) on Tuesday June 27, 2006 @08:47PM (#15617437)
    More expensive to dig, harder to cross roads/othershit when digging, MUCH easier to repair above-ground lines than below-ground lines (all you need is a cherry-picker truck), and what would squirrels walk on if there weren't above-ground power lines?
    • what would squirrels walk on if there weren't above-ground power lines?

      From my squirrel observations, I would assume they would walk on wooden fences, grass (lawns), tree limbs, my bird feeder... just to name a few. I think it would be safe to assume that if squirrels ever learn how to surf the web, they would visit squirrels.org [squirrels.org].
      • Sadly, a squirrel walking on the powerline near my house decided to play "mmm, this transformer looks tasty" and ended up exploding himself... though he didn't affect the power (it did, however, cause me to crap my pants thinking that something of mine exploded).
    • Backhoe power outages are much less likely to happen with overhead power lines. There's also shovel outages, which took out the phone lines to my neighborhood once (dam cable company).
  • They are here, generally. Where do you live?
  • by justchris ( 802302 ) on Tuesday June 27, 2006 @08:51PM (#15617454) Homepage
    The workers prefer overhead lines.

    It's true that underground lines require less maintenance. A lot less maintenance. If we changed all our lines from overhead to underground, NES would have to layoff 4/5 of their maintenance team. Rather than realizing that it would take years to convert every powerline in Nashville from overhead to underground so they'd have excellent job security until they retired, they have decided not to convert to underground lines. I wouldn't be surprised if this is true in other areas, but I know that's the deal here. So everytime there's a thunderstorm the power goes out, and the cable goes out with it, cause the cable lines follow the powerlines.

  • Interesting Story... (Score:4, Interesting)

    by chriswaclawik ( 859112 ) on Tuesday June 27, 2006 @08:55PM (#15617468)
    I live in Madison, which is near Spring Green, which is where Taliesin is located. For those not in the know, Taliesin was the home/studio of world famous archictect Frank Lloyd Wright. When driving up to his house for a tour, I noticed the highways near it looked a little "bare." Later on, I discovered that Frank Lloyd Wright not only owned the house/studio, but acres and acres of land around it. And he HATED power lines, because the way that they disturbed the natural prarie. And since he was infamous for not caring about budgets and practicality, he paid to have every single power line on his estate buried.

    And you know what? I'd say it looked pretty damned nice.

    You know what else? I sound like a old rambling grandpa. I remember in my day to get to Taliesin we had to walk 5 miles uphill both ways in the snow...

  • Simple physics (Score:4, Informative)

    by loony ( 37622 ) on Tuesday June 27, 2006 @09:02PM (#15617497)
    Each cable that transports AC is subject to drain by the capacity the parallel lines themselves represent. The closer the wires, the higher the capacity. At about 30 km on a regular high voltage cable, you reach a point where the reactive power drain reaches the maximum power the cable can transport - the cable is saturated without draining a single watt at the end.

    DC does not have this issue however then you have all the problems that killed Edison's original DC power distribution in favor of Telsa's AC distribution.

    Peter.
    • by dex22 ( 239643 ) <plasticuser@gm[ ].com ['ail' in gap]> on Tuesday June 27, 2006 @09:54PM (#15617710) Homepage
      The answer to this is simple. Instead of running both wires from the power station to the customer, run one each way. As one cable is now reversed, the current will now not be in opposition. As you know, the opposite of destructive interference is constructive interference. You could get twice as much power out of that line as you put in!

      Another answer is to move the users closer to the power stations! We should make the stations smaller and have more of them. What if every transmission pole was a power station? We should put a solar panel on top of every pole, and if we spin it around at 60 RPMs, voila! A/C!
    • Re:Simple physics (Score:4, Informative)

      by coyote-san ( 38515 ) on Tuesday June 27, 2006 @11:06PM (#15618078)
      Are you sure that isn't inductance?

      Anyway, we're almost certainly talking about different things. Nobody is suggesting burying long-distance high-tension lines. Just the last half-mile or so. That's enough to eliminate the visual clutter and keep the neighborhood from losing power after a tree limb breaks, etc.
      • Re:Simple physics (Score:3, Informative)

        by Technician ( 215283 )
        Are you sure that isn't inductance?


        Yes he is sure. In any wire there are a few factors causing problems getting power from one end to the other without loss. First is resistance. Too much current simply heats the wire. Power lost in the wire is power put in and not delivered to the other end.

        In addition to resistance, two conductors near each other are a capacitor. Capacitance goes up if the conductors are placed closer together or are larger, or the material between them is something other than a vacu
  • "With storms getting worse and worse (Maryland, DC and Northern Virginia have weathered torrential downfalls this week), might underground lines prove more resistant to storm-related power outages?"

    I have some friends in the Baltimore area. There has been severe flooding in the area.
  • Water (Score:4, Insightful)

    by Undefined Parameter ( 726857 ) <.moc.oohay. .ta. .modeerf4leuf.> on Tuesday June 27, 2006 @09:07PM (#15617513)
    My apartment complex has its power fed in through a buried line, and I can attest to one good reason why power companies may not want to bury all (or even most) of their power lines: water.

    My power has gone out three times already, this year, due to water seeping in where it shouldn't and causing a major short. Aside from the obvious risk of losing power, there's also the possibility of pedestrians and pets being electrocuted.

    ~UP
    • Re:Water (Score:3, Informative)

      by geekoid ( 135745 )
      your electric company has either improperly maintain there line, or incorrectly designed the underground system. In general undground lines or less prone to outage.
      over a 10 years study, outages where less and the duration of outages was shorter.

      what aren't people electrocuted when the rain has soaked the power polls and lines?

    • Re:Water (Score:5, Interesting)

      by CerebusUS ( 21051 ) on Tuesday June 27, 2006 @09:25PM (#15617581)
      There was an article in the Chicago Reader a couple of weeks ago about pets (and people) getting electrocuted from lines that were buried 40 or more years ago and were now corroding or fraying. It can actually cause wet concrete to basically act like a large shock plate. Not fun. It's also very hard to detect.

      Here's a link to the article summary, [chireader.com] though you'd have to pay $2 to actually read it.
      • Re:Water (Score:5, Informative)

        by Technician ( 215283 ) on Wednesday June 28, 2006 @01:49AM (#15618802)
        pets (and people) getting electrocuted from lines that were buried 40 or more years ago and were now corroding or fraying.

        We have learned from our mistakes. All newer high voltage buried cable is coaxal in design. The hot conductor is surrounded by a grounded jacket. A fault shorts the cable to the grounded jacket tripping the overcurrent protection instead of putting lots of voltage to the ground.
  • by Ellis D. Tripp ( 755736 ) on Tuesday June 27, 2006 @09:08PM (#15617516) Homepage
    Underground powerlines would suffer higher capacitive losses than overhead lines, and losses between the generating plant and the user would be power that the utility company can't (directly) bill for.

    With all the public concern about EMF exposure, the situation would be made much worse when all those distribution transformers move from 40' up a pole to concrete pads at ground level. And then there is the everpresent problem of "backhoe fade"...
    • by peragrin ( 659227 ) on Tuesday June 27, 2006 @10:24PM (#15617860)
      actually this is the big point. Power companies can massively undersize wires that are traveling in free air.

      Three conductors in free air 15 feet off the ground the power companies can run a #2 sized cable for 200 amps. Yet that same wire underground needs to be 4/0 or 250 MCM which is several times larger.

      The cost of goods to run lines over head is considerable less even if you take into account storms trashing it. Just from a dollar point of view you can competely rebuild a surface grid two or three times for the cost of doing it once underground. Digging costs that much more. Digging near roads is even worse.

      I think it makes long term sense to go underground but I do see the cost advantages of going above. Plus the union can hire more people.
      • New York City loses a lot of power because of their old and beaten underground power grid. Everything from rotting insulator to wires that aren't in use, but never had their current shut off.

        Their layout also manages to zap people & pets during the winter/wetter parts of the year.
    • by TubeSteak ( 669689 ) on Tuesday June 27, 2006 @11:36PM (#15618188) Journal
      Reminds me of this thread
      The Backhoe, The Internet's Natural Enemy [slashdot.org]

      Always carry a length of fiber-optic cable in your pocket. Should you be shipwrecked and find yourself stranded on a desert island, bury the cable in the sand. A few hours later, a guy driving a backhoe will be along to dig it up. Ask him to rescue you.
  • Two words: Fire Ants (Score:3, Interesting)

    by davidwr ( 791652 ) on Tuesday June 27, 2006 @09:11PM (#15617525) Homepage Journal
    In the Southeast United States fire ants are a big problem. The just love low- and medium-voltage electricity.
  • Footpaths (Score:4, Informative)

    by MavEtJu ( 241979 ) <[gro.ujtevam] [ta] [todhsals]> on Tuesday June 27, 2006 @09:17PM (#15617548) Homepage
    Here in Australia, or at least large (for big values of large) amounts of it, it's all above ground too. Where I'm coming from, the Netherlands, it's all below ground.

    When I discuss it with the people here, they give me all kind of reasons why it should be above ground (limited but not only to unable to quickly repair, the famous cable cut from people digging and, believe it or not, the people who are doing the repairs now would be jobless).

    Just a quick glance about how it could be done and you'll see that it would be quite a trick anyway: All footpaths in Australia are large blocks of concrete or asphalt, and the nice small tiles you see in shopping centers are also just laying above a concrete layer. Opening up that would be a major++ operation. Compare it to the Netherlands where all footpaths (and most of the bicyclepaths) are just 30x30 cm tiles laying on top of yellow or black sand, you'll see that it has a historical tradition to put things underground and have them easily accessible.
  • But wouldn't underground lines be more susceptable to flooding and/or earthquake failure? Also wouldn't it be a lot slower to fix any problems that do happen with those? It's very quick to throw up a new pole. I can't imagine that safely digging a new trench, or tracking down leaks underground is very fast.

    Having power out for an extended period effects people more (and are harder to privately circumvent) than more, quicker outages.
  • by philgross ( 23409 ) on Tuesday June 27, 2006 @09:30PM (#15617601) Homepage
    We could continue to debate this endlessly, but maybe you could save time and just read the official report [eei.org]?

    I'll also mention that 4 of the 5 NYC boroughs (Manhattan, Brooklyn, Queens, and the Bronx) have their electricity distribution almost entirely below ground. It was a massive investment, but it was long ago.
  • by Tanmi-Daiow ( 802793 ) on Tuesday June 27, 2006 @09:38PM (#15617635) Journal
    I work for an electrical contractor in Eastern Iowa and we regularly have to work near these high lines and work with the power companies. As far as I can see, it is exceedingly expensive to bury these wires. There are alot of farmers around here and they regularly hit buried power lines when digging in their fields. This is a often an expensive and timely problem to fix involving the power company, an electrician and usually a whole day. I noticed the article doesn't say maintenance issues. From my experience, they need less maintenance, but the particular maintenace is very costly in money and time.
  • by EQ ( 28372 ) on Tuesday June 27, 2006 @09:43PM (#15617665) Homepage Journal
    The same reasons most houses in coastal areas of Florida and other sandy-soil areas near water don't have basements. Water pushes right into them.

    Try putting underground *anything* in gulf-coast Florida, etc.
  • Nice doomsday quote in there, Editor. Have you seen "An Inconvenient Truth" ?
  • DIffers (Score:4, Interesting)

    by JanneM ( 7445 ) on Tuesday June 27, 2006 @09:53PM (#15617709) Homepage
    In urban areas in Sweden it's all below ground. It's in part, I believe, because of snow; rural areas (where underground cables become far too expensive) have a predictable power outage mess every winter as some storm weighs down lines enough to break them (cue predictable news images of army units clearing snow off calbe poles and some farmer with no backup generator milking his cows by hand). It's also because of zoning laws - power companies have no choice. I believe much of nothern Europe at least is similar in this regard?

    Here in Japan, on the other hand, it's all above ground. In part because of the relative lack of zoning laws (Japanese city architecture is delightfully, ah, surprising as a result), but according to people here it's mosty because of the prevalence of earthquakes, the one thing buried cables are not protected against. Sure, overhead cables will break too, but it'll be easier to fix.

    I can understand the situation here in Japan, but really, it's a pretty hideous sight. So your power may end up getting slightly more expensive as a result (though this is dwarfed by other factors), but it's worth it. If saving money is all there is about city living, why not allow people to dump their trash in the street as well?
  • I think this depends on when the power grid was put down. In philadelphia (at least the city proper ) has its power underground. Interestingly my phone and cable are above ground and strung through the back between the buildings while power and gas is under the street somewhere and comes through the front of the house.
  • by gregmac ( 629064 ) on Tuesday June 27, 2006 @10:18PM (#15617825) Homepage
    Something no one has brought up is the ability to upgrade technology. With above-ground poles, it's fairly simple to string along additional wires as needed. If you're undergound and you run out of phone lines, the telco may just say too bad, wait 6-18 months until there's enough demand to dig up the neighbourhood. If the city is rolling out fiber-to-the-home, the undergound neighbourhoods are likely to be the last to get it. Most likely they won't get it until the road needs to be dug up anyways to replace the surface, or sewer or water lines.. That can take 20-30 years, or even longer sometimes.

    My parents live in an area with everything undergound. It definately looks nicer, but their cable reception is on some channels is terrible, and has been that way for years. They've had the line going up to the house replaced and all the inside wiring replaced, but it's still not as good as it would be. Replacing the main line in the road would mean digging up the bottom couple feet of 50-60 driveways (most paved, some interlocking brick.. you usually can't find the exact same replacement bricks either, so it would never look the same). It's just not practical to do to fix a few snowy channels for a handful of houses (I'm not sure exactly how many people have the problem, but their immediate neighbours do at least).

  • Thermal and electrical. For above ground, you do not have to shield the cables to prevent conductance between them. On the flipside, high tension wires generate a
    non-trivial amount of heat and burying them might aggravate the situation?
  • Induction (Score:5, Funny)

    by ValentineMSmith ( 670074 ) * on Tuesday June 27, 2006 @10:42PM (#15617954)
    Just think, if they buried them, we'd be able to run a loop of copper around them. Free power for life, or at least until the power company noticed an odd drop in the current on my run.

    Well, I can dream.

  • Power Sink (Score:3, Interesting)

    by Doc Ruby ( 173196 ) on Wednesday June 28, 2006 @12:34AM (#15618465) Homepage Journal
    New Orleans had all kinds of power systems underground, including powering their pumps. When Katrina hit, they flooded and failed, just like they did for years in smaller storms.

    If New Orleans didn't learn to do it different before Katrina, why should we learn to do it different after Katrina?
  • by UnixRevolution ( 597440 ) on Wednesday June 28, 2006 @02:35AM (#15618982) Homepage Journal
    Switching to underground power would require not just the upkeep of underground wires:

    Underground wires will require insulated wire to replace much of the uninsulated wire used in overhead lines.

    Underground wires will require that thousands of miles of trenches be dug.

    Underground lines will require that houses have power inlets underground rather than on the roof, as present.

    Underground lines will require that Millions, if not billions, of towers and poles be constructed.

    Underground lines will require pole-top transformers be moved to ground level or below.

    The costs of converting are staggering, and will take probably at least a decade.

    As a resident of the DC suburbs (southern MD to be precise) we aren't having too many power outages due to these recent storms. Mostly flooded roads.
  • by Zx-man ( 759966 ) on Wednesday June 28, 2006 @03:43AM (#15619202)
    As weird as it may sound, quite a number of small towns here, in Ukraine have their powergrids (mostly) underground. It is so because in the 90s it was not uncommon for every piece of cable/wiring to get stolen sortly after being installed. So, back in day it used to be financially effective. Now with crime rates down it, probably, would not be worth the price, thought. But it stays as it was.
  • Externalities (Score:3, Insightful)

    by massysett ( 910130 ) on Wednesday June 28, 2006 @07:25AM (#15619743) Homepage
    Let's assume (though this is far from obviously true) that underground lines are indeed more reliable. Having a reliable electric supply generates lots of positive externalities--and of course unreliable power has large negative externalities.

    The problem is that the positive externalities generated by the underground lines would not be captured by the power company. Even if the buried lines generate benefits to society far in excess of their high costs, the power company would see only a fraction of those benefits (e.g. less money spent on repairs, assuming that's even true.) The cost, though beneficial to society, is prohibitive to the utility.

    Possible solutions of course involve government subsidies to bury the power lines, or perhaps requiring them to be buried and allowing the higher cost to be passed to consumers (for instance in Maryland, where electricity has been deregulated, it's only the generation of power that's deregulated. Retail delivery is still regulated.)
  • by CFD339 ( 795926 ) <{andrewp} {at} {thenorth.com}> on Wednesday June 28, 2006 @02:07PM (#15622740) Homepage Journal
    Powerline transmission in the US covers vastly more distance per end user than in most of the world. At the same time, the pace of change and growth in virtually every town in city in the country is so very rapid that underground placement would require much more frequent changes and retrenching. Above ground transmission is better suited to this environment.

    As a firefighter, I have had on many occasions to stand by near broken transmission lines or transformers to wait for power company repair trucks. While it seems to the person sitting at home to take a very long time, let me assure you it seems longer for the poor bastard standing in the rain or snow waiting. That said, when there is a problem that is isolated they usually show up within minutes. During a storm, they make every effort to prioritize based first on danger, second on the number of outages that can be fixed in a single repair, and dead last based on cost. When we have a reported fire, they drop everything to get to where we are as quickly as possible to disconnect service to the location -- so that we can be able to do our work more safely.

    I've never met a single careless or lazy power company lineman. I suppose any that start out as such are soon quit or dead.
    • Working with electric utility clients through the years, and going to industry trade shows, I've heard this topic discussed by knowledgable folks many times. It should be obvious to most people that, if underground cabling were a no-brainer with no tradeoffs, then it would already have been adopted in lots more places (though there is already a good deal of it in use). The various utilities are independent, and make their own decisions. There's no conspiracy to blot the skyline.

      Andrew points out two importa

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