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Thanks for sharing. More evidence that power lines should be under ground. Can you really not fly your drone "around people"? I thought you could fly in parks.
by hellbanner 9y ago
Thanks for sharing. More evidence that power lines should be under ground.
Can you really not fly your drone "around people"? I thought you could fly in parks.
- devwastaken 9y agoI thought power lines, in contact with the dirt, can make the ground electrocutive.
- WJW 9y agoPerhaps I don't understand what you mean by electrocutive, not being a native English speaker and all, but in my home country of the Netherlands over 90% of power lines have been underground since the 50s without any ill effects...
- k-mcgrady 9y agoInsulate them?
- verall 9y agoThe cost of insulating a 765kV power line is prohibitively high. Although in the modern day it might make sense to move more low voltage power lines underground than did previously.
- astrodust 9y agoPlus unless that insulation is made of something we haven't invented yet it's bound to flake and peel off in time.
- trentmb 9y agoDowned power lines, yes.
- benzofuran 9y agoIt creates a voltage gradient radiating out from the contact point. A gradient of more than 15VAC/m is generally bad news. The resistance can be enough to prevent automatic circuit protections from tripping as well if there's not a high current, such as dry high-resistance soil.
- thomasgaukel 9y agoYou can fly your drone around people as long as those people don't include me.
- eugenejen 9y agoof course underground power lines will be more expensive for the moment. So will drones produce more values than the cost to invest on underground power lines? https://en.wikipedia.org/wiki/Undergrounding https://en.wikipedia.org/wiki/Undergrounding Advantages Less subject to damage from severe weather conditions (mainly lightning, wind and freezing) Reduced range of electromagnetic fields (EMF) emission, into the surrounding area. However depending on the depth of the underground cable, greater emf may be experienced.[2] The electric current in the cable conductor produces a magnetic field, but the closer grouping of underground power cables reduces the resultant external magnetic field and further magnetic shielding may be provided. See Electromagnetic radiation and health. Underground cables need a narrower surrounding strip of about 1–10 meters to install (up to 30 m for 400 kV cables during construction), whereas an overhead line requires a surrounding strip of about 20–200 meters wide to be kept permanently clear for safety, maintenance and repair. Underground cables pose no hazard to low flying aircraft or to wildlife. Much less subject to conductor theft, illegal connections,[3] sabotage, and damage from armed conflict. Burying utility lines makes room for more large trees on sidewalks,[4] which convey environmental benefits and increase property values [5] Disadvantages: Undergrounding is more expensive, since the cost of burying cables at transmission voltages is several times greater than overhead power lines, and the life-cycle cost of an underground power cable is two to four times the cost of an overhead power line. Above ground lines cost around $10 per foot and underground lines cost in the range of $20 to $40 per foot.[6] In highly urbanized areas the cost of underground transmission can be 10-14 times as expensive as overhead.[7] Whereas finding and repairing overhead wire breaks can be accomplished in hours, underground repairs can take days or weeks,[8] and for this reason redundant lines are run. Underground cable locations are not always obvious, which can lead to unwary diggers damaging cables or being electrocuted. Operations are more difficult since the high reactive power of underground cables produces large charging currents and so makes voltage control more difficult.[citation needed] Whereas overhead lines can easily be uprated by modifying line clearances and power poles to carry more power, underground cables cannot be uprated and must be supplemented or replaced to increase capacity. Transmission and distribution companies generally future-proof underground lines by installing the highest-rated cables while being still cost-effective. Underground cables are more subject to damage by ground movement. The 2011 Christchurch earthquake in New Zealand caused damage to 360 kilometres (220 mi) of high voltage underground cables and subsequently cut power to large parts of Christchurch city, whereas only a few kilometres of overhead lines were damaged, largely due to pole foundations being compromised by liquefaction. The advantages can in some cases outweigh the disadvantages of the higher investment cost, and more expensive maintenance and management.
- deleted 9y ago[deleted]
- Raphmedia 9y agoHere are the rules in Canada: https://www.tc.gc.ca/media/documents/ca-opssvs/Infographic_-_New_rules_for_recreational_drone_users_EN_2.pdf https://www.tc.gc.ca/media/documents/ca-opssvs/Infographic_-... "[Do not fly your drone:] closer than 75 m from buildings, vehicles, vessels, animals, people/crowds"
- bdamm 9y agoIn the US the law is that you MUST fly your drone within 121 meters of buildings, vessels, or the ground.
- king_magic 9y agoWithin 121 meters? Which law is this?
- PhasmaFelis 9y ago> In the US the law is that you MUST fly your drone within 121 meters of buildings, vessels, or the ground. That's true! Except just the ground, not buildings or vessels. So, not true at all.
- raverbashing 9y agoYes they should be That being said, it's still the responsibility of the operator to not collide with anything in the air
- joering2 9y agoThats most likely heavy guarded by lobbyist. On average while in transmit, power companies get 20% more of electricity just by putting cables in the air.
- slm_HN 9y agoNo, you cannot fly your drone over people. The exception being surveying construction sites as it is assumed that people on construction sites are already wearing hard hats. Ironically parks, which would be an ideal place to fly, are often no-fly zones. For example all national parks in America ban drones as do many state parks.
- loeg 9y ago> Ironically parks, which would be an ideal place to fly, are often no-fly zones. For example all national parks in America ban drones as do many state parks. That doesn't stop people, in my experience.
- astrange 9y agoMost parks I've seen people try to fly in near SFBA are no-fly zones because they're too close to airports.
- m-j-fox 9y agoMy office is pretty-much on the runway of SJC and the vacant lot next door is a favorite for lunchtime RC enthusiasts.
- mtanski 9y agoGoogle search for "drone national park" and you'll find out why.
- pgrote 9y ago"Why did the NPS restrict unmanned aircraft? The National Park Service embraces many activities in national parks because they enhance visitor experiences with the iconic natural, historic and cultural landscapes in our care. However, due to serious concerns about the negative impact that flying unmanned aircraft can have for safety of visitors, staff, and wildlife, they have been restricted in all but a few parks."
- 9y ago
- patorjk 9y agoYou can fly them around people, you're just not supposed to fly them over people [1]. However, if you're flying commercially, you can get a wavier for this. [1] https://www.faa.gov/uas/getting_started/ https://www.faa.gov/uas/getting_started/
- robbyking 9y agoInterestingly enough, almost all transmission lines in San Francisco are underground; almost all of what you see overhead are either telephone/cable, or overhead wires for powering MUNI, our municipal light rail.
- astrodust 9y agoLong-haul lines in North America are rarely buried, the cost is too high. One notable exception is Quebec's grid which, after the disatrous 1998 ice storm which brought down a huge portion of their lines, buried them to avoid a similar catastrophe in the future.
- evilDagmar 9y agoTennessee had the same thing happen at about the same time. They still aren't burying power lines.
- deleted 9y ago[deleted]
- lavezzi 9y agoI mean wouldn't that be an issue for areas with tectonic activity? I wouldn't imagine they would be as easy to repair if they were under ground.
- thaumaturgy 9y ago> More evidence that power lines should be under ground. I agree in principle, and there are places that do this, but there are a lot of practical considerations too. A neat story about what it's like when there's a failure in a big underground line: https://stuff.mit.edu/afs/net/user/tytso/archive/high-power https://stuff.mit.edu/afs/net/user/tytso/archive/high-power In California, you have problems with tectonic movement -- even small fault activity will stretch, relocate, and damage buried lines. In nearly everywhere else, you have underground water tables seeping in around your buried lines. None of these are insurmountable, but they don't make it an easy job either.
- hellbanner 9y agoDIdn't consider tectonic movement, good points