7 ms·
What's wrong with below-ground power distribution for metropolitan areas?
by gmueckl 2y ago
What's wrong with below-ground power distribution for metropolitan areas?
- alephnerd 2y agoIt's time consuming and expensive to implement due to a mix of property rights and construction.
- foota 2y ago"There is no easy fix" underground power lines for an entire city isn't easy.
- blantonl 2y agoThere's nothing wrong with it. But it would take lifetimes of money and time to retrofit a city like Houston to move all power infrastructure underground. And there is no way consumers would ever sign up for the cost to do so. It would be akin to building the Hoover Dam today. It would probably be one of the largest public works projects ever attempted.
- mym1990 2y agoLifetimes of money, really? What is that measurement? Someone above said 2.5 million per square miles. Catastrophic damage from larger storms is often in the tens to hundreds of billions of dollars, so it feel like it would be in the best interest of most parties to embark on this project, even if it happens slowly.
- throwup238 2y agoPutting power lines underground wouldn't mitigate very much of that damage though, would it? I was under the impression that the vast majority of those multibillion dollar figures is water damage to buildings, cars, and other equipment.
- tstrimple 2y agoJust one anecdote. We lived through the deracho in Iowa, one of the places hardest hit. Huge swaths of the city was without power for weeks. In our house, in the middle of the most damage, was without power for under 24 hours. That's a massive difference. I don't know how much the calculations take into account physical damage versus all up damage including lost productivity. But many of the folks working at the local company were back "in the office" working from home because the business was without power far longer than most of the employees. I have no idea how the overall damages are calculated.
- Qwertious 2y agoA lifetime of money is ~$10M or so. That's $100k/year for 100 years.
- Sam713 2y agoThe poster above misstated the cost. Its $2.5mil/mile. That number actually comes from PG&E in California, so its possibly not relevant to Houston. I couldn’t find that Centerpoint has actually done an analysis for Houston. Just to get an idea of scale, Centerpoint states on their website that they operate ~33,000 miles of above ground power lines. Source: https://www.khou.com/article/news/news-explainers/the-why/houston-power-lines-buried-why-not/285-fc0cf7a6-50e5-497f-96c9-065c0e01c33b https://www.khou.com/article/news/news-explainers/the-why/ho...
- quickthrowman 2y agoIt’s not lifetimes of money, but there are substantial costs. All of the existing distribution conductors need to be buried either by trenching or directional boring, all of the pole-mounted transformers need to be replaced with pad-mounted transformers , and all of the customer service drops need to be converted from overhead to underground. In another post, someone said about $2.5M per square mile, which isn’t actually all that much money. If you figure half labor and half material costs (fairly standard for electrical construction) and labor costs of $100/hr (IBEW 66 journeyman lineman), that’s 12,500 hours of labor, or a 6.25 person crew for one year to convert one square mile, and Houston is 637 square miles. ~4,000 person years of labor, 400 full time linemen could do the whole city in 10 years.
- bob1029 2y agoHouston is gigantic. Maintaining underground infrastructure can be very difficult. https://practical.engineering/blog/2021/9/16/repairing-underground-power-cables-is-nearly-impossible https://practical.engineering/blog/2021/9/16/repairing-under...
- KingOfCoders 2y agoBerlin, 3.645M citizen, everything underground. Houston, 2.302M citizen, ... "gigantic"
- bdcravens 2y agoIt's not a matter of population, but land. Berlin is about 345 square miles; Houston is 640.
- KingOfCoders 2y agoBerlin including suburbs ("Speckgürtel") is ~1400 square miles.
- BenjiWiebe 2y agoSo approximately 1/7th the size of the Houston metro area.
- bdcravens 2y agoIf you includes the suburbs, the Houston area is roughly 10,000 square miles. https://en.wikipedia.org/wiki/Greater_Houston#Geography https://en.wikipedia.org/wiki/Greater_Houston#Geography
- tstrimple 2y agoAnd thus their additional challenges are caused by their absolute neglect of urban planning. If only someone could have predicted that spreading single family housing over hundreds of square miles was going to create a maintenance nightmare.
- spyspy 2y agoMuch more expensive to install and maintain, and while risk from wind and rain is lessened, you add the risk of any below ground construction accidentally severing cables.
- FredPret 2y agoI’m not an electrical or civil eng, but I imagine it’s very expensive to dig so many tunnels. Groundwater (especially for coastal cities) and people drilling holes would be very problematic too.
- FrustratedMonky 2y ago"not an electrical or civil eng. So let me explain how impossible everything is that I don't know about, and snidely say it's just 'physics'".
- hedora 2y agoAssuming you don't hit rock, it's not bad. Power lines that are rated for conduit burial (which implies indefinite direct submersion in water is fine -- conduits leak, even if they're not supposed to) are readily available and not particularly expensive vs. above ground lines. Most of the cost is in the conductor, and that's the same either way. If memory serves me right, you need to trench 6ft (which is usually done with a backhoe that has a narrow bucket and straddles the trench), then place a PVC pipe to act as conduit and fill the trench. The last step is using a (typically) pickup-truck mounted cable puller to pull the line through the conduit. If the wire fails, you can pull it out and put a new one in without retrenching. When you bury the conduit, you also bury a piece of warning cloth about one foot above it. If you see that while digging, then you should stop digging. (Also, call the "call before you dig" number before you dig.) There are also trenchless systems that I've seen used for fiber optic cables. It's basically a tiny little boring machine (like they use to bore holes for tunnels) on the end of a cable. One person steers the boring machine, and the other stands above ground with a metal detector that tells them where it is, and how deep.
- KingOfCoders 2y agoStandard in most of Europe.
- bdcravens 2y agoNothing, but migrating to it is very expensive. Centerpoint, the physical electricity provider in Houston, has said it would cost $2.5M per square mile. Houston is 640 square miles. Regulations allow them to claw back costs on the bills. (For example, repairs from past storms are often paid for over the course of several years in the form of a bond that is applied to customers as surcharges) https://www.houstonchronicle.com/business/energy/article/centerpoint-storm-repair-costs-consumer-bill-19473150.php https://www.houstonchronicle.com/business/energy/article/cen...
- tigerBL00D 2y agoIt seems like a lot, but a few billions of dollars also seems like a good deal to secure against increasing risks for severe weather. What's the total economic impact of future storms? To put it in perspective a single Patriot missile battery costs about a billion dollars and a single missile costs $4M.
- hedora 2y agoThere are about 3844 people per square mile in Houston, so that's $650 per person, amortized over at least 20 years, which would increase the monthly power bill by about $2.70 per person (~ $10 / subscriber?) I'd guess that's less expensive than throwing out everything in the fridge / freezer every few years.
- analog31 2y agoAlso less expensive than everybody going out and buying a generator, plus putting out fires from improperly stored gasoline.
- bryanlarsen 2y agoPenny-wise, pound foolish. This single 1 week power outage is going to cost Houston a lot more than $1.6B.
- _wire_ 2y agoFunny to think about these costs and the health of the national commons from a point of view of the Federal budget. For example, you point out it would cost 2 billion to migrate Houston's above-ground to storm proof below ground. If we could lop off 1/4 of the DoD and intelligence budget of $1T/yr and dedicate it to infrastructure, we could pay for 125 Huston-scale improvement projects per year. And still have the most expensive DoD in the world! But that would be misguided for "national security". Plus the Federal budget is essentially free money, constructed as needed, where such value is incarnated via the wealth of the commons, where such wealth is most truly incarnated by infrastructure. But for unknown reasons, such pragmatism is politically untenable.
- AdamH12113 2y agoWhat I've always heard whenever this subject comes up in Houston is that A) burying lines is expensive (and Houston is very large), and B) Houston floods a lot.
- seanmcdirmid 2y agoNew Orleans and Houston are basically built on swamps. In New Orleans, you can’t even bury people below ground, so I doubt you can do much with power lines underground.
- hedora 2y agoIt turns out we don't need to speculate: https://www.sciencebase.gov/catalog/item/64650dded34ec179a83dbad6 https://www.sciencebase.gov/catalog/item/64650dded34ec179a83... Most of the wells they sampled are > 100 ft above the water table. Some are as low as 12. The lowest is 2.83ft. Here's the relevant bit of the schema XML document for the CSV the produced: <attr> <attrlabl>DTW23</attrlabl> <attrdef> December 2022 through March 2023 depth to groundwater in feet measured from land-surface elevation referenced to NAVD 88 </attrdef> <attrdefs>U.S. Geological Survey</attrdefs> <attrdomv> <rdom> <rdommin>2.83</rdommin> <rdommax>453.97</rdommax> <attrunit>feet</attrunit> </rdom> </attrdomv> </attr>
- MisterBastahrd 2y agoI used to live in a neighboring parish to the west of New Orleans. If you dug more than 3 feet into the ground, you were hitting water. Driving pilings is a sloppy mess.
- yread 2y agoIn Amsterdam the ground water level is also very high but people manage to put lines in the ground
- seanmcdirmid 2y agoSo this is weird, but I never saw people buried above ground in Amsterdam like in New Orleans. What the diff? Even if cremation is common now, it probably wasn’t a hundred or two years ago?
- robocat 2y agoSwamp is a poor excuse IMHO. Plenty of my city Christchurch is built on swamp. yet it has slowly been replacing HV and LV power poles with underground cabling for about 50 years now, although there is still some remaining. We don't get hurricanes so I'm not sure of reasons for us using underground cabling. NZ is no where near as wealthy as Texas so Houston should be able to afford to do it too. Christchurch gets earthquakes instead of hurricanes: http://db.nzsee.org.nz/SpecialIssue/44(4)0425.pdf http://db.nzsee.org.nz/SpecialIssue/44(4)0425.pdf
- atmavatar 2y agoI'm getting strong "'No way to prevent this' says only country where this regularly happens" vibes.
- dpkirchner 2y agoIt's funny to me that folks counter criticism of Texas by saying lefty California also has outages. It's like, sure, they do -- so why not show that a right-wing government can do better? What is the actual point of the counterargument?
- gosub100 2y agoI think "vibes" is a new weasel word that subtly absolves the author from any responsibility to connect cause and effect. There's a whole lot more to writing than announcing what "vibes" you get.
- amanaplanacanal 2y agoI understand what they meant.
- bluGill 2y agoMoles, mice, things walking/driving over the top. There is a long list of things that make underground not nearly as reliable as it sounds.
- bequanna 2y agoUnderground electric distribution is considerably more reliable than overhead lines. Animals digging up the wire is much more rare than an outage created by an animal crawling up a pole and grabbing the line/transformer. Underground electric is quite widely used in the Midwest and is cost effective vs. overhead lines even in sparsely populated rural areas.
- 15155 2y agoBelow-ground power distribution is cheaper in sparsely-populated rural areas than overhead lines because utility companies can trench the lines directly through anyone's field or in any random ditch - there's no directional boring required (until customer delivery possibly.) Add in the fact that you no longer risk trees taking down lines when they are unkempt and ice-covered and it is probably much cheaper.
- alphabettsy 2y agoDoesn’t seem like it would be cheaper anywhere.
- galdosdi 2y agoSource? The grid was far more reliable where I've lived with underground than overhead lines. Kind of hard to believe. Sounds like that would only happen if your city cheaped out on the conduit material.
- bluGill 2y agoBeen thirty years since I lived there, but when I lived where there was a coop electric they had data showing underground was overall less reliable. Maybe things are diffarant now.
- adrianmonk 2y agoIsn't there a third option: redundant overhead power lines? In the transmission (long haul) part of the grid, there's already a lot of redundancy. But not as much in the distribution (last mile) part. If you increase redundancy, you should be more resilient to e.g. trees knocking out power lines because there are multiple paths in more parts of the network. I doubt full redundancy (two lines to every customer) would be realistic, but an increase in redundancy seems like a more practical way forward than just starting over completely with underground lines.