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PG&E will bury 10k miles of power lines so they don't spark wildfires (npr.org)
353 points by boulos 13 days ago | hide | past | favorite | 283 comments





When they say 10k miles, do they mean 10k miles of land or of cable? Asking because my military unit used individual cables to exaggerate numbers. i.e. 6 strands at 1 mile would become "6 miles of cable run". Either way, great they are doing this. I hope they prevent some fires and save some lives.

Reminds me of a story a colleague told me, from his early job working in tech support call center for a phone company.

He recounts of an issue with a customer complaining about low Internet speeds, despite being located close to the distribution building for the whole area. Seemingly, everything should've been fine. A cable leaves the distribution building, goes into the ground, and reappears a short distance later near the customer's house. Upon close inspection it was discovered that the cable did not take a straight route underground - instead of cutting the cable to necessary length, someone just buried the entire spool, and the total cable length was close to a kilometer or so. The signal, unboosted, barely got through to the other end.


Ohmuhgawd, this is so bizzare. That cable is not free, and wasting that much of it was surely to get noticed, wouldn't it? Questions, so many questions. Was this a contractor sticking to the man by wasting all of that cable? Was it someone trying to earn points for how much cable they "installed" that month? Wouldn't it be more financially beneficial to cut the cable as normal, and then sell of the spool to a scrapper or other used cable place? Was this a team of people that all agreed this would be a bad idea?

So sounds like a movie plot


My guess is too lazy to cut and re-terminate the cable.

Ordinary cable installation does not dig a hole big enough for a spool to fit. They tend to dig trenches just wide enough for what they are burying. They would have had to have done so much extra work for that.

Just lends itself to the story possibly being an urban legend.


The things I've seen 'round here in the telecom boxes and fiber concentrators... It's a miracle anything works at all...

In the early days of consumer DSL, I had really, really bad service and I kept calling to complain and the phone company kept saying they found nothing wrong. Finally they must have gotten tired of me calling and they sent someone competent. He traced my phone cable all the way back to the box a couple blocks away then came back to tell me that he found the problem. One of the wires in the pair was not actually screwed down (or punched down, IDK): it was just touching the terminal. So some of the time it worked just fine, but I'm guessing that if a big truck or something drove by, the vibration separated the connection, and my DSL would go all to hell.

His guess was that (a) nobody bothered looking in the box and (b) they were just testing voice quality, which was fine, but the actual DSL signal was showing lots of dropouts.


Maybe the install department had extra budget to waste before the end of the year, so it wouldn't be cut next year.

It’s a typical non-disclosed denominator issue.

As mentioned in the NPR story, it's about 10% of their distribution and transmission lines.

"Last night I moved 60 trillion meters of DNA downstairs to get a drink. I was thirsty."

We're taking a different approach in Australia (the state of Victoria specifically), and not only are we replacing bare wire overheads with buried cables [0], we are also implementing Rapid Earth Fault Current Limiter (REFCL) technology to lower the risk of bushfires due to downed wires. [1]

When powerlines come into contact with the ground or a tree, arcing can occur. If the line remains live and continues arcing, the risk of fire is quite high.

REFCL tech works by detecting the phase-to-earth faults that occur when a one of the three-phase powerlines breaks and falls to the ground. REFL instantly reduces the voltage on the fallen line, and boosts the voltage on the other two phases. REFCL will then test the faulted line after a few seconds, and if the fault was intermittent full service is restored. If not, the whole line is removed from service to prevent fires and make the line safe to work on.

On Total Fire Ban days (very high risk of fire due to weather conditions), the REFCL settings operate at increased sensitivity.

There's a requirement in Victoria that by 2023 all high risk zone substations have to install REFCL technology, and all HV customers connected to those zone subs have to be REFCL compliant (their equipment must be able to handle the over-voltages that occur during REFCL operation).

[0] https://www.energy.vic.gov.au/electricity/powerline-replacem...

[1] https://www.energy.vic.gov.au/safety-and-emergencies/powerli...


> REFL instantly reduces the voltage on the fallen line, and boosts the voltage on the other two phases.

I didn't get how that would work, so I did a bit of research. REFCL effectively grounds the affected phase so that it is 0V with respect to ground. But the other 2 phases retain the same voltage relative to the affected phase, so they have increased voltage relative to ground.

https://www.ausnetservices.com.au/-/media/Files/AusNet/Commu...


Additionally, we have increased patrols of the wires in regional areas, installation of spreader bars, and regular clearing of the trees and shrubs near the wires.

Not using bundled/sheathed ABC overhead cable? Or was that too expensive relative to the remaining risk.

I'm not super familiar with power systems, but as far as I've seen in Australia, higher voltage ABC mostly only comes in 11 or 22kV (distribution), not 33kV and up which this seems to be talking about (feeder/transmission).

You do seem to be able to buy 33kV ABC from China but not sure if it would meet Australian Standards.

Looking at Wikipedia's page on ABC though, it says that even older 11/22kV ABC is being replaced to underground in Australia because the insulation can degrade and it can cause fires too.


I have a question I haven’t seen anyone address so far: how much can we expect this to reduce the frequency of wildfires? Intuitively, to me, the effect would seem to be negligible. All of the conditions for wildfires will remain in place. It’ll simply be something else that lights the spark. If it’s not power lines it’ll be lightning.

So then to follow up: what is the point? To deflect blame from PGE? And who pays for it?


Electrical power causes about 10% of wildfires by number [1], but it's responsible for 7 out of the 20 most devastating wildfires [2]. Perhaps this is because power-line fires happen disproportionally in remote, unattended areas, where they can grow large and uncontrollable before firefighters arrive.

It probably won't solve wildfires - there's still plenty of fuel, and hotter climates, and strong winds - but it can buy some breathing room. I suspect a bigger reason is to maintain the integrity of the grid. Buried power lines don't start fires, but they also don't get taken down when there is a fire, and they won't have a judge order them shut-off when there's a risk of high fire danger. Being perceived as an unreliable source of electricity is a far bigger threat to a utility than burning down a few towns - I know that was the primary reason I went solar, and a lot of my peers are also thinking of disconnecting from the grid because the grid isn't there when you need it.

[1] https://www.sfchronicle.com/bayarea/article/How-California-s...

[2] https://www.pbs.org/newshour/science/californias-catastrophi...


You have just convinced me that fires will get worse. Every time there is a fire it cleans out all the fuel, so if 10% suddenly go away, that means when the next fire happens there is more fuel for it.

If there isn't any "critical infrastructure" which can be damaged nearby the fire, smaller intentional burns can keep fuel accumulation low.

Except no one wants to take the risk that the small fire becomes a huge one - or the smoke will aggravate someone’s asthma then next town over and get sued. Yes, that is a real reason I was quoted from a CalFire rep as to why they had to stop prescribed burns in a major fire risk area in the Sierra Foothills.

Still a very problem. In pre 1800 California, Forests burned every 3 years and summer was a perpetual haze. Historic burn acreage was around that of 2020. The intensity of these fires is what is new

Is it the instensity, or the fact that people are now trying to live in these prone areas? In pre 1800 California, this area was just wild lands. In post 2020, the humans are like cock roaches crawling in every crevice of the lands (just a slight exaggeration).

There multiple problems.

One is the fire intensity for people who enjoy the outdoors and using them. High intensity fires destroy the natural resource and some will take a century to grow back. This is especially worry some because we are essentially locked into all of our forests burning down at this point.

Impact on people and homes is an entirely different one that I honestly care less about, because it affects me less.


I'm part cockroach on both my mom's and my dad's side, and I take slight offense at that statement, and wiggle my whiskers in disapproval.

> Except no one wants to take the risk that the small fire becomes a huge one

Generally controlled burns are scheduled during wetter seasons for this reason. But the difficulty of getting the general public to understand this and go along with it is probably hard to understate.


It still happens that they get away from the firefighters sometimes [https://wildfiretoday.com/tag/escaped-prescribed-fire/]

With very high fuel loads, the consequences get worse as time progresses, and the odds of it happening get higher - at least without tons of manual shredding and other fuel work first, which is expensive, and what a prescribed fire should alleviate the need for.

In the modern legal/liability environment, it’s tough to do - if you do the inexpensive thing (still expensive) like prescribed fires to reduce the catastrophic risk, you get sued.

If you do the safer option (mastication, lop and scatter, etc) you can only touch tiny areas at a time - and the catastrophic risk rises.

Logging can help, but it also requires management and care to not make the problem worse long term, and in many of these areas it’s a non-starter due to environmentalist pushback. Even if we ignore the cost in money, it delays things for decades sometimes - and by then it’s probably burned down.


Good luck getting permits for a proscribed burn in California.

Is it that hard? Or maybe it varies by area? I see prescribed burns happening all the time where I live in California and also frequently get notifications about them, so that people don't call in the smoke. And I live in an area that is both considered to have the very most extreme environmentalists and the most NIMBY of people you will find anywhere.

Seems like the fire department would be the one signing off on permits and they would probably be the ones overseeing that same prescribed burn. If you can get permits all over the state to have huge fireworks shows during fire season, I don't see why they couldn't do prescribed burns.

While the fire department can (might or might not) issue permits, courts are known to stop the burns for years while various parties sue to stop them. All the while things build up worse and worse.

You're almost certainly correct, since that's what a state oversight committee found in 2018 [1], but this perspective was criticized harshly by the media when Trump mentioned the same.

[1] https://lhc.ca.gov/report/fire-mountain-rethinking-forest-ma...


What service do you have where your grid connection is that unreliable? Is it PG&E? Is it due to their "cautiousness"?

Not op, but PG&E shut off the power to over 2 million people for 3ish days due to high wind fire risk back in 2019: https://en.wikipedia.org/wiki/2019_California_power_shutoffs...

In 2020 it was probably a grand total of 20 days, and restoration took days.

> the grid isn't there when you need it.

> What service do you have where your grid connection is that unreliable?

I am in Ercot, right next to where the natural gas pipelines begin and where regulation ends, and I also struggle to keep the time on all of my appliances week-to-week. I don't know how the EI grid is doing, but feels like reliability has been dropping like a rock west of the Mississippi since ~2014 or so.

I used to have a computer plugged directly into the ATX power grid that had ~3 years of uptime. What a fantastical time that was.

Now, I am currently having a 50kW standby generator installed (oversized for multi-day operation). I am also investigating multiple fuel sources and smaller auxiliary units. Have to think in 2nd order terms these days. Everyone else is getting a generator installed too.


In-laws installed a generator after a hurricane, maybe 15 years ago. Next hurricane with major power outages they were still sol- so many generators kicked on, combined with gas wells shut-in for the storm, meant the gas grid collapsed.

They immediately had a propane backup tank installed that could run things for 2 weeks.


Yes, it's PG&E. It's a combination of their cautiousness and their incompetence. Sometimes the power will just go out for reasons unrelated to PSPOs (public safety power outages).

If someone views a modern electrical utility in a Western country as unreliable then they either have no idea what they are talking about or have unreasonable expectations.

See NERC's reliability report for 2020 - even accounting for fires, the average transmission capacity loss for the entire USA and Canada was mostly under 0.5%. (Page 65)

https://www.nerc.com/pa/RAPA/PA/Performance%20Analysis%20DL/...

Solar and batteries aren't a substitute for grid transmission infrastructure and cannot match the amounts of energy a good transmission grid can deliver. The best part of the grid - you don't have to worry about balancing or when you need energy. You just flip a switch.

Yes, PG&E could have done more and their investment choices led to lots of damage and loss but let's not jump the gun and term their grid unreliable. They are held to NERC's standards which are among the best in the world.


I think the poster was making the subtler point that while average performance will be good, that might be heavily weighted towards those living in urban centres.

If some outlying customers switch to partial or full self sufficiency, then a utility "death spiral" can occur as they increase prices on the remaining customers in the area.

Two responses to this are:

Legally force people to stay connected and pay for the grid

Start building microgrids using distributed solar and batteries, which is apparently being done in remote Australia.

Either can be a good thing if well managed, or an inefficient boondoggle if not.


right and i get that however, it's not a viable solution at all. A big reason why the current transmission network is so reliable is because of scale. You cannot recreate scale even if you band together with your neighbours to build a microgrid and you certainly cannot achieve scale on your own.

Outlying customers are difficult to service in regular times because there are many failure points and few redundancies. The solution to this is not for every farm to install solar PV as a substitute to the grid but to shore up transmission and distribution infrastructure.

Anyone who's lived in the high arctic will tell you that the #1 reason they are clamouring for connections to the continental grid is reliability. Solar, wind and even diesel generation are just not as reliable or sustainable.


It's not about pure reliability numbers, but rather control. If my only source of electricity is the grid, then when the grid goes down, there is literally nothing I can do about it but wait and hope while all the things I use grid electricity for slowly fall apart. Whereas if I have some local generation, I can retain some functionality regardless of what the grid operators do.

Solar has the further advantage that it doesn't require ongoing fuel, so you're not dependent on that infrastructure either. Sizing a battery system to accommodate your usual lifestyle while it's dark is a bit silly, but a modest amount of storage that can supply say an average of 200W will get you quite far (fridge, sump pump, lighting, internet uplink, laptop).


Yeah, I think we generally agree. You see some people talking about solar and battery storage as if it makes (or is intended to make) each home self-sufficient, when the reality is that homes with solar and batteries that are also connected to the grid is the mainstream future.

Solar installs on e.g. remote mining sites are already starting to conplement and then edge out diesel generators so there are off grid use cases but if you have a grid then the most efficient thing is to use it in most cases.

But outlying customers in sunny areas are almost certainly going to benefit financially and in terms of reliability if the grid encourages them to install PV and batteries that talk to and work with the grid. Whether a grid owner will actually be incented to do so is a different question.


> If someone views a modern electrical utility in a Western country as unreliable then they either have no idea what they are talking about or have unreasonable expectations.

This is making the error of substituting average performance for the actual performance of a particular grid. The PG&E grid shuts down large amounts of transmission during high wind events:

https://en.m.wikipedia.org/wiki/2019_California_power_shutof...

> Solar and batteries aren't a substitute for grid transmission infrastructure

This is proving to be very wrong. Transmission is extremely expensive, it can be one of the most expensive parts of the grid, and, both batteries and distributed solar are being used as a substitute for transmission.

The term in the industry is "non-wires alternatives," and it was a way for early lithium ion batteries to be used profitably on the grid, even before their recent price drops. (That and frequency regulation in the PJM market).


For posterity - NERC's report addresses fires specifically and even breaks out individual fires. Yes, people losing power in California happened for extended periods but many more people did not lose power and PG&E was not the only utility implicated there. Besides, natural disasters happen yearly and if you read NERC's report, you'll see that there are far more outages due to storms than wildfires.

My only gripe here is that this by itself, does not quality PG&E's grid as "unreliable".

As for non-wires alternatives, I can point to several reports, some from NERC, some NREL and others private companies that have found - over and over again - that the path towards more grid reliability involves better transmission and stronger distribution. Batteries and solar can delay the investment needed, not substitute them altogether.


There are some unintended consequences of shutting off the power preventively though. Two seasons ago someone had switched on the three generators they had installed because of these "high-winds" shutoffs, one of which caught fire and ended up causing a medium-sized brushfire here, I think on the order of a few thousand acres IIRC. It was in one of the canyons around here, fairly rural, but very near lots of suburbia.

It’s like enforcing a policy of not smoking next to the pumps at a fueling station.

... in a world where 4channers can anonymously spray sparks at gas stations and do it for the lulz, and it costs $1000 each time you tell someone to stop smoking at the pump.

(That is, the policy is expensive, and there are numerous other hard-to-monitor causes of fires.)


I think there’s a big fire underway right now that PG&E thinks was probably set by two of their electrical fuses. Burying fire in dirt stops fire, so removing the power equipment from direct exposure to oxygen and tinder by burying it in dirt is a really effective way to stop electrical sparks from leveling up into wildfires.

You might send a manhole cover into near earth orbit now and then when an underground transformer explodes. As the famous saying most definitely does not go: One small leap for manhole cover, one giant leap for not celebrating your fifth anniversary of burning down ratepayer homes and national parks.

(As you might suspect, they’ve been making tidy profits every year for decades while choosing not to invest in burying power lines. The only reason there’s been such rapid change and a proper incident reaction in IT terms for an actual megacorp, is that they’re in bankruptcy court and the judge can compel them to act competently and rapidly, and shame them and penalize them for failing for the fourth year in a row to do so. Non-US folks, our power utilities are a mix of for-profit and not-for-profit, and ethical behavior that costs money is less common in for-profit ones. Co-ops are usually a good idea, but megacorps not so much.)


PG&E doesn’t really make that much money from serving those more rural communities and houses where those fires are likely to occur. They subsidize those higher cost to serve areas with all the money they make in the big urban areas that aren’t at risk at all. Burying lines will just cause urban areas to subsidize urban areas even more, when there really should be some consequence for deciding to build your house in or abutting a dry forest with the need to have power brought in through that forest.

In many cases these are transmission lines between urban areas that cross rural areas.

Or in the case of the Camp Fire, we're talking about a transmission line constructed in the 1920's to carry hydroelectric power from the Sierra Nevada to other areas-- primarily Contra Costa County.


If that is true, then how do rural-only power companies outside of California provide much better service at much lower prices than PG&E?

Also, running a mile of power line in a California city is orders of magnitude more expensive than running a mile of power line in rural areas outside of California. To the extent that PG&E follows the law (sometimes they just steal the money, and blow up towns years later when the system decays), I doubt they make much profit in the city.

At any rate, PG&E prices are completely out of control in rural areas. All in, I paid ~$10K for a 5 foot run from an existing transformer. All they did was run three wires five feet, and re-energize their own transformer.

It took them three years.

In the meantime, we built a house with a gas generator and Lithium ion batteries.

I’m not including that expense in the $10K, nor am I including delay of construction or wiring on our side of the PG&E box.

I am including the second pole and power backing board they had us build because the first one (built to their specifications) was unacceptable.

Edit: Also, they made us bury our lines, but refused to bury theirs in a reasonable timeframe. Hopefully we’ll get buried service lines out of this.

Edit 2: I forgot. They refused to give us permission to move our box to eliminate their unburied lines. So, it wasn’t that we wanted them to pay to bury the lines. We wanted their engineers to sign off on moving a transformer, and then decommissioning their lines.

Since then, they’ve had people on our property multiple times to deal with trees that interfere with the line they wouldn’t let us pay to eliminate.


Burying in urban areas is expensive but you don’t have so much length to bury. The work is also amortized by high population density.

They definitely make all their money in cities, most utilities do. The monopoly license to operate in a city makes servicing rural areas tolerable, but everyone would avoid servicing them at the same rates if they didn’t have to.


I absolutely agree that the incentives to build homes in/by forests need to be rethought, or at least handled better at the building code / enforcement level.

I'm no accountant, but if you go bankrupt as a result of an activity then the activity likely doesn't count as profitable. Cash flow positive, yes. Profitable, no.

Profitability and bankruptcy sit in a mild opposition to each other.


> if you go bankrupt as a result of an activity then the activity likely doesn't count as profitable

Unprofitable for the shareholders, maybe.

The CEO still gets to take home $6M+ [1] which sounds plenty profitable to me.

[1] https://www.mercurynews.com/2021/04/08/pge-execs-pay-raises-...


PG&E is usually profitable; the cause of their bankruptcy is all the damages and fines levied as punishment for their part in starting wildfires.

what you armchair accountant aces don't know is, years ago top PG&E management found a way to take out a lot of capital and capital gains from PG&E, even though PG&E is tightly regulated. New top-level holding companies were formed. They were using this top-level capital structure to purchase other financially performing assets, like power plants in other parts of the US. This was uncovered during the ENRON blackout response.

I believe that many US companies have made distinct fortunes based just on capital asset valuations, along with some strategic sales and trades here and there. PG&E is in the center of that, being a massive landowner for its infrastructure. Second fun-fact, when California State regulators requested inventory details for things like transmission facilities, the response was "trade secret" or "homeland security" or "you will sell this info" .. basically deny, delay and deprive. So even the agencies tasked to regulate PG&E did not have complete asset inventories to refer to..

If anyone has info on the current court-ordered restructuring since the criminal negligence conviction, don't be shy !


Do you have any citations to back these claims up


This is what I was hand waving at (the tendency to Enron-ify) but you have way more specifics than I do. Thanks!

If they are found to be the cause of the fires, then this was probably a predictable outcome. If it is a predictable outcome, the accountants would probably do something like accrue a liability for causing forest fires.

They might have made a mistake about how much they accrued in the past, but going forward they wouldn't be able to call the decision profitable. It clearly wasn't.

If a business goes bankrupt, at least one of its past decisions was an unprofitable one. That is a difficult fact to escape from.


Damages and fines levied are part of the "costs" side of a balance sheet. If those costs outweigh the revenue, then the business is unprofitable. I think I can see the point you're trying to make, with a distinction between the usual running mode, and abnormal circumstances imposed from an external source. I disagree with that point, as no company exists in a vacuum. The laws and regulations of their environment may impose costs, and those are part of the cost of doing business.

i think the fine was something like 15e9 USD. It is interesting to see what happens when financial penalties for bad corporate behavior are large relative to profits.

>Burying fire in dirt stops fire

Not so fast ! https://en.wikipedia.org/wiki/Coal-seam_fire


Now I wonder if coal is more electrically conductive than dirt as well as thermally susceptible. Could you ionize a coal vein? Maybe we can transmit AM radio with it and map it with a heavy metal detector!

It's carbon so there much be conditions in which it's semiconductor or conductor-like. But even if those occurred naturally, they'd have to occur consistently throughout a seam for it to be carrying radio waves. In any case coal dust should have pretty good electric capacitance. Combine with flammability...

Fortunately, California has a very low incidence of coal fires.

> what is the point?

Presumably the point is to bring affected parts of California back to the first world by not having to shut off their power whenever there's heavy winds expected.


One distinction versus naturally caused fires (like lightning) is that power lines are often downed by high winds over dry terrain. Lightning, usually, is accompanied by a storm so there’s at least some rain.

It’s not going to stop everything, nor all human-caused fires (e.g., the “gender reveal” one last year), but I believe it shifts the likelihood more than you expect.


The biggest effect will be that they won’t have to trigger blackouts during high winds to prevent downed lines from starting forest fires. For those in the affected area, that’s a big deal.

But if CA wants to reduce these fires, they desperately need to catch back up on their controlled burns. A combination of low brush fire for decades (not forest fire!) and changing environment has built up an extremely dangerous backlog of fuel that makes CA specifically and the PNW in general a massive fire risk. Short of fixing global warming and moving everyone away from the interface between nature and city, the only solution is to burn up all that fuel in a controlled way.


This doesn't apply to CA, but in general it is a good idea for most of the world.

The vegetation there has been on natural cycles for years of burning hot every few years. Sure power lines start the file, but they will start anyway: large hot fires have always been part of the life cycle of that area. This is very different from the low brush fires that are a natural part of most other forests.


CA has huge fires partly because they suppressed the low brush fires that were more common a century or two ago. Because they’re now decades behind on the natural burns that would normally happen every summer, the state will have to work overtime to catch back up to a safe equilibrium.

To be fair, climate change and changing habitation patterns are also making this much worse.

https://www.motherjones.com/environment/2019/11/californias-...


Fire intensity in California is absolutely related to frequency.

Historically, most California forests had low intensity burns every few years. Now, these same forests haven't had a fire in 100+ years, resulting in extremely intense fires that leave behind ashen moonscapes. This is not the historic normal fire cycle in CA.


If only conditions matter, but triggers do not, why don’t all forests catch fire all at the same time when it gets dry enough? Think about it: average forest in California will probably get dry enough to support forest fire at least every few years. Why then it takes decades or centuries until the fire actually visits them?

Triggers are necessary for fires, obviously, but getting rid of the triggers does not solve the problem. There's another wrinkle to the whole matter: when a forest survives the dry season without burning down it doesn't reset. The following year there will be even more dead wood and other dry material in the area. This means next year's potential fire will be even worse than the last.

One step at a time. Forest management is a huge issue. Wildland firefighters are zealous, almost paramilitary organizations that try to vanquish every fire like enemy invaders. In reality, fires are part of the lifecycle of forests that clear brush and make the forest healthier and more resilient in the future.

At least nowadays wildland firefighters spend plenty of time conducting prescribed burns, too. They're not chuckleheads - they're perfectly well-aware by now that past practices contributed to the problem.

But they are hired by and paid by politicians who know smokey the bear and don't care at all about the modern science of forests. Not to mention courts regularly block their attempts to control the forest (ironically often by lawsuits brought on by environmental organizations) As such they often are not allowed to do the right thing for the forest even though they know what to do.

>In reality, fires are part of the lifecycle of forests

Let's be absolutely clear that this is only true for a limited number of forests. The evidence for this is the existence of very old trees.

Unfortunately many forests will become increasingly susceptible to fire as dry seasons are extending in many areas due to climate change.


> The evidence for this is the existence of very old trees.

Lots of tree species are able to survive a forest fire once they reach a certain size. There absolutely are very old trees in areas that burn frequently.


"Very old trees" generally means fire-resistant old trees, and frequent but mild fires regularly affecting the less-flame-resistant undergrowth.

There is a limit on how much dry wood a forest can accumulate. At some point old dead wood will rot and become soil. Though in dry climate rotting is slow.

That is interesting. I thought rain reset the conditions.

Rain can make it worse by adding more growth that then dries out and becomes fuel.

https://en.wikipedia.org/wiki/Fire_triangle: “a fire needs to ignite: heat, fuel, and an oxidizing agent (usually oxygen)”

There also always is plenty of oxygen. In dry summers, there’s also plenty of fuel. What’s lacking is sufficient heat. The ignition temperature of wood is difficult to assess, but wood can start burning at 125°C ≈ 256°F (https://www.warrenforensics.com/wp-content/uploads/2016/06/P...)

It doesn’t get that hot without help, e.g. from a campfire, a magnifying glass, or sparks from electricity.


Or lightning. Lightning can and does happen without rain, too.

There are many long term economical effects of burying electric, not only does it reduce exposure to liability (you caused a natural disaster), it also reduces maintenance cost, failure rates and so on. Both customers and providers prefer buried cables, all things being equal. The only issue is that they're more expensive to actually place, so maybe them causing wildfires has finally pushed companies to put the cables where they belong.

As a corollary - maintenance of buried power lines is more expensive due to all the digging which has to be done. Power line inspection is also trickier.

I also wonder if the unions representing linemen have a strong influence on "bury" vs "overhead" since most of lineman's job involves work up a pole rather than a tunnel.

Lastly - burying anything in the ground in areas where the ground has been known to move (California is the "Earthquake" entry in the Bingo game of "choose which natural disaster" that is the continental USA) is liable to be a non-trivial endeavour, one which will require ongoing inspections and the like.


There are lots of good reasons distribution companies don't like cables in some situations (especially rural). Connecting new customers and network alterations is much more expensive, changing to a higher voltage is not possible, upgrading capacity requires a whole new cable which is more expensive than replacing the conductors, cables only last about 30-50 years. Finding and fixing a cable fault usually takes much longer than overhead (although there are probably less of them per mile). Without wild fires, I seriously doubt cables are more economic in rural areas.

> how much can we expect this to reduce the frequency of wildfires?

A point to keep in mind here, PGE is a company. Their primary goal is to not be the cause of the wildfire and pay damages. If it also reduces the frequency of wildfires, great.


NB: there's PG&E (Pacific Gas and Electric), and PGE (Portland General Electric). Whilst their service areas differ (PG&E serves California, PGE serves Oregon), they're near enough and similarly-enough named that the distinction is useful. Both are for-profit companies.

The article here refers to PG&E, Pacific Gas and Electric, an investor-owned private utility serving California.

https://en.wikipedia.org/wiki/Pacific_Gas_and_Electric_Compa...

https://en.wikipedia.org/wiki/Portland_General_Electric_Comp...


Because it's cheaper than paying $13.5B when it was your equipment that started it. This is nothing more than liability mitigation. And once complete, even if you don't maintain them, buried cabled generally can't start fires.

https://www.washingtonpost.com/nation/2019/12/06/pge-reaches...


I think you've hit the nail on the head. It's not entirely insignificant, but it certainly is not the driver of wildfires. If we perfectly buried all the power lines, we'd have fewer fires, but we'd still have most of the fires we already have.

The primary problem remains fire suppression practices, forest management, and changing climate. This seems like a very expensive way to eliminate a quarter of our wildfires.


As someone who lives 15 miles from Paradise, CA - A “very expensive solution” makes it sound like there are inexpensive solutions that would be just as effective. If there were, wouldn’t PGE have implemented them?

Maybe its just “the solution”.


PGE is more concerned about the billion dollar law suites. This solution makes economic sense to them.

But doesn't help the fire. As long the dry woods are piling up, which it eventually will, something else will trigger the fire. And amount of fire won't be even reduce by 25%.

But the court won't be able to blame PGE then, that's the whole point.


This, exactly. A PGE power line probably sparked the deadly Paradise fire, and I've repeadly see people blaming them for the deaths with metaphorical pitch forks in hand, completely ignoring the far more complex reasons for people being unable to get away from that fire safely.

In Quebec, Hydro Quebec trims trees and shrubbery from wires every summer.

This is much, much cheaper than burying them, and they hire students going into forest, and related fields to assist with the work (heavily supervised).

It is not even remotely hard to believe that Quebec has far, far more rural power lines than California.

What's the difference? State run organizations like Hydro Quebec, are IMO not apt to create short term profits, by sacrificing long term cost saving measures. There is no CEO of Hydro Quebec getting a massive boost to income via stock profits, or awards due to profit targets met.

The goal is instead, make delivery the safest and most cost effective over the long term.

By burying wires, I suspect it achieves two things. Ensuring a CEO, or department head won't cost save for a bonus, and not trim wires, and to maybe do a one time write down.

To highlight this?

I accidentally had a tree fall the wrong way (I has ropes too, one slipped) during a cut. Hydro Quebec came and cut the tree from the wires, restored power, for free.

In Ontario, where power is private now? I would have paid thousands.

Why the difference? The loss of life, because someone tries to save money and deal with it themselves, isn't worth it. Especially when state paid health care, and disability exists.

I'm 100% a capitalist. Yet some things make sense, run as a non profit, where costs are counter to societal safety and goals.


>What's the difference? State run organizations like Hydro Quebec, are IMO not apt to create short term profits, by sacrificing long term cost saving measures. There is no CEO of Hydro Quebec getting a massive boost to income via stock profits, or awards due to profit targets met.

Not really. While it's true that a state run organizations might not cut costs to meet profits, that's just replaced with cutting to meet budget requirements. eg. https://www.nytimes.com/2017/11/18/nyregion/new-york-subway-...


This is where Canada's concept of a crown corporation works quite well.

It is established with a specific mandate by a province or the federal government, but run at a pretty long arm's length while still being accountable to the legislature. Some crown corps, like Hydro Quebec, produce their own revenue, so they have some market incentives to perform and are not subject to the whims of the annual government budget.


>It is established with a specific mandate by a province or the federal government, but run at a pretty long arm's length while still being accountable to the legislature.

Doesn't that describe PG&E? It's run at "long arm's length" from the government because it's a private company, but it's also accountable to the CPUC.

> Some crown corps, like Hydro Quebec, produce their own revenue, so they have some market incentives to perform

What are these "market incentives to perform", and how does it not lead us back to square one with "these companies will cut costs to boost profits"?


It's worth pointing out the US already does this. For instance, the Tennessee Valley Authority is a Federally-owned utility, and the sixth largest in the country.

There are lots of other examples like this outside of utilities. The US Postal Service, Amtrak, the Export-Import Bank, and many others.


PG&E might have private investors but it doesn’t do anything with the Public Utility Commissions oversight.

And they trim trees in CA too, but unlike QC which is typically green in the summer, CA is typically full of dry vegetation and a spark in the grass is still going to start a massive fire.


"To deflect blame from PGE?"

I think that's the major part. It will look good for them from an ESG perspective. Also, I think some states, like CA, are talking about making the company pay for any fire starting from their equipment. So they are probably hedging that risk. If they wait, it could take them too long to complete the burial and then still be subjected to penalties under new laws in the future.

Edit: why downvote? These steps may reduce a small percentage of wildfires (10% from electric utilities and PG&E isn't the only one). I think the main reasons they are doing it are what I stated about. I doubt the company truly cares about this unless it reduced the financial risk and helped them in the ESG space.


The point is that it increases profitability of the utility (by expanding the rate base), and so the customers are paying for it. If they get some good publicity and it marginally decreases fire risk those are secondary benefits.

My guess is that fire prevention is only part of the problem. Wouldn't burying the lines mean that their infrastructure is also not destroyed by wild fires? Things just burn above, and everything keeps on working?

The point is to avoid lawsuits not wildfires.

Be mindful that it's not exactly the number or size of the fire they are optimizing for, but the cost.

And I guess some smaller fires might cost a lot, if they are near rich people's estates.


There's no point, you're right. On the other hand, there is no money shortage. I wish the government ordered PG&E to make poles ready for fiber instead.

Makes more sense to put down fiber with the power cables. Why would you want to it on poles?

Because digging entrenches incumbents.

We did this in Denmark many, many years ago. It is also significantly cheaper to maintain as you no longer need to manage vegetation around the powerlines, perform pole / cross-arm inspection etc. In some countries the main hesitation to underground cabling for transmission lines has been up front cost as well as unions (=less maintenance, less work).

20 years ago my local power company did the math and discovered underground was more expensive to maintain. Underground you don't need to maintain vegetation, but the lines break more often, and are a lot more expensive to replace.

This obviously depends on local conditions. Where I lived then there was plenty of water so starting a large fire was not possible. The plenty of water also meant the ground wasn't stable. Of course they did need to maintain vegetation, but that is a known cost.


I'm interested what would cause underground cables to break more often. Is it people not "calling before you dig" and accidentally severing them or is it something else?

Ground moves, especially in California. Sometimes it’s subsidence, sometimes landslides, sometimes it’s seismic related, sometimes it’s frost heave or the like. Properly studied and buried (with proper backfill) usually is protected, but big enough changes will cause problems.

Throw in backhoes, erosion, etc. along with it being more expensive to fix when it does break, and overall it isn’t always guaranteed buried will be cheaper maintenance wise.


The slightest crack will allow ground water in shorting out the wires. Cracks are somewhat common after a few years because the ground moves via the yearly freeze-thaw cycles we have up north.

It would be pretty ridiculous if a little water could short out a buried transmission line. Do you really think generations of engineers haven't figured out how to protect buried lines from ground water?

I don't know what PG&E will use in this case, but all buried power and transmission lines lines are robust against water infiltration. Solid-dielectric cables are rated for direct burial, and cooled lines are encased in steel conduit. Both types are sometimes further protected in concrete.


Engineers encase the cables in rubber or plastic, which degrades over time. Or steel pipes which rust over time. there are things we can do about this, but they just add time. When you only have a little bit of cable odds are it lasts, when you have thousands of km odds are there will be constant problems.

Good thing we don't really have any more ground water in California. /s

Rodents enjoy chewing on them and the chemicals they use to discourage them only last so long.

Code is for me to bury little tiny cables in my backyard 24" down. These giant mega cables have to be at least 36" down, right? Are rodents going 36" deep and eating into cables really a thing?

at 15,000 volts or whatever, that rodent will only do that once

A RODENT is a redundant occurance of dentifrication of electrical networking technology.

There's always another rat (or squirrel, or rabbit, or mole, or ...)


That's because they always remove the carcass. You're supposed to leave the carcass of the first one as a warning to all of the others.

Growing up, this was something that occurred multiple times a year. Squirrels would climb the poles and short themselves across the 2 leads on the transformer. Zap, one less squirrel, and several hours without power while the power company came out to diagnose the problem and then send out for a replacement.


You had the power company replace the squirrels?

Independent vendors are faster, cheaper, and offer a more locally-adapted product.


Wasn't expecting someone to be on dangling modifier patrol!

The squirrels seemed to replace themselves without servicing. If only the transformers were capable of the same thing.


Be thankful it's only the modifiers I'm patrolling ;-)

This is very valuable information if true, can you provide some sort of references?

It’s pretty common sense. Underground breaks cost more to fix because you have to dig the line up both to find the problem and fix it. Above ground problems are visible while underground problems are invisible.

Not to mention that above ground lines have slack between poles while underground lines are pulled relatively taut. Any shifting in the ground is going to result in a break underground before a break above ground. Above ground lines are also better founded because the poles are sitting on foundations or driven deep so their ability to resist ground motion is a bit better while electric lines move with the ground around them pretty much in sync. This is particularly important in seismically active areas like CA but underground infrastructure actually typically performs better in actual seismic events.


You don’t have to dig up the entire line to find a break. This is a common misconception. Signal reflection can be used to determine the distance to a break.

see: https://en.m.wikipedia.org/wiki/Time-domain_reflectometer


You still have to dig it up to fix it.

"Common sense" does not always equate to facts or relevance.

While, yes, the cost to dig up a line is likely to be higher than the cost to repair a hanging line, that's just one cost and consideration. Economic loss due to wildfire as well as rolling brownouts to try and avoid wildfire are both costs you'd need to consider. You also have the cost to maintain vegetation around powerlines, vs basically no pre-emptive maintenance on buried lines (and little to no weathering).

And you, of course, have differing likelihoods of the line breaking in any case, which means the per-fix cost is only part of that picture. Lots of potential reasons, but I'd be curious to see a full study on those reasons for both above ground and below ground, their potential solutions, and their potential costs, but without that you have a very fuzzy picture.


When you're getting hit with class action lawsuits and killing people left and right, I don't think the math adds up. If the electrical lines were underground PG&E stock wouldn't have dropped from 70 dollars a share to 9 which reminds me

"lo barato siempre es más caro"

The cheap is always more expensive.


Why would you have to consider all these costs you’re talking about when it’s been made clear that these power companies will not be allowed to fail and will be bailed out by the government (but never taken over because they’re a convenient whipping boy)?

Another 2 cents. Drones are very popular for being able to quickly look at above ground lines. You can easily & quickly determine if parts are in need of repair or soon will be. I don't know if a similar thing exists in underground without building some type of complex tunnel system.

Imagine it was significantly cheaper if you measured it over a 3+ year time-span.

Not over a 1-2 year time-span.

The unwillingness of corporations to minimize OpEx by taking on significant one-time CapEx, in order to pretty the books, lives on in so many domains.


Minimizing OpEx is one of the main drivers of telcos to switch to fibre. Companies like Bell Canada are telling their shareholders that network maintenance costs will drop as copper is decommissioned and services are migrated to fibre.

Another important factor is that highly regulated local monopolies like power companies may have certain restrictions like only being able to charge a certain % over cost. Well, you'd much rather have 5% of a large number than a small number, so you're incentivized to do the more expensive long term thing.

It definitely explains a lot of what PG&E has done sometimes - maximum inefficiency and cost in some areas, incredibly (long term destructive) cheap in others.

Health insurance has been doing this too.

They've been doing this in California for the last 40+ years. PG&E is just a prime example of why de-regulation doesn't work. LADWP which is a publicly owned utility ran the Scattergood-Olympic Transmission Line (11 miles) under the city nearly 5 years ago and LADWP actually generates revenue for the city of Los Angeles. Honestly, PG&E needs to die in bankruptcy court.

I thought it was significantly more expensive to bury high-voltage transmission lines because the current corrodes the insulation needed to bury the lines, so you have to dig up and replace every 20-30 years. I was actually quite surprised to learn that above-ground transmission lines in the US are uninsulated for this reason.

No, the insulation in a solid dielectric transmission lines is cross-linked polyethylene, or paper in fluid-cooled lines. Lines are designed to operate well within the thermal capabilities of the insulation, and there is no such thing as routine replacement of undamaged underground lines.

Above-ground transmission lines are uninsulated because they don't need to be, and the extra weight of the insulation would require more expensive towers.


Yes and no. It's a power company that owns the right-of-way where there lines are located. They will still keep that land cleared of any vegetation they don't want. I'm honestly surprised they don't just use RoundUp over the entire area of their right-of-way.

Did what exactly? Most the transmission grid at least is overhead lines in Denmark. In fact, it is said that putting more than 15% of transmissions lines underground would be irresponsible due to physical limitations of AC lines, which corrupts the transmission system.

That is true. But the distribution system is largely UGed. My OP was meant to say Dx not Tx.

The upfront cost is why we don't generally do this in the US. If we looked at it from a 50 year perspective we'd (probably) do it in a heartbeat but we aren't very good at that sort of planning ahead.

If they were managing the vegetation the wildfires wouldn't really be an issue though. It's California though so know doubt a friend of some PGE board member just started a company that buries power lines at an exorbitant cost.

How do other places with dry forested areas deal with this? Are there similar regions from which California should be learning?

Also, if we get a major earthquake, are they going to have to dig all the lines up again?

Also, can we just note how crazy it is that this company blew up a neighborhood, burned down a town, was convicted in these separate incidents, and is still allowed to have a monopoly on power for a broad region? Why are corporate convicts apparently treated so well, but natural persons who are convicted are treated so poorly?


Those places burn too.

You want electricity, right? PG&E is one way to get it. You could replace the people in charge, you could replace the owners, you could even nationalize the whole thing and you still have the same problem: Vast amounts of incredibly expensive, aging infrastructure, drying climate, and homes built into the wildland boundary interface.

There's no magic trick that will solve this problem. The money for electrical upgrades will have to come from taxpayers and/or ratepayers; there isn't anyone else. And it will only reduce the probabilities of big fires. The huge Carr fire in Redding was started by sparks from a towed trailer. The LNU complex last year was lightning (plus one guy trying to cover up a murder with arson). It's not all electrical... probably not even a majority.


Just take the money from the profits lol

There won't be any profits if they actually go ahead and fix it. You'd have to claw it back from prior shareholders who benefited from that unethical behaviour.

Perth's metropolitan region in Western Australia has the largest percentage of underground power in the world. Granted, a large portion is in suburban areas and I suspect entirely in the distribution network not the transmission network. It's climate is very similar to much of California.

Power infrastructure on this magnitude requires an extraordinary amount of capital investment to set up. Who takes on their debt? The operating expenses for asset management and maintenance of a mature network are eyewatering when compared to their underground counterparts as there is a lot more numerous and frequent replacement activity for parts. Pole infrastructure may have a life span of 10-15 years but some parts will be replaced out every 3-5. Before you know it you pay for every pole 4 times over it's life. Now multiply that by several hundred thousand poles in a large network and then you start to get the picture. I'm not trying to be an apologist but I'm surprised from what I hear of American infrastructure that it's not a far more regular occurrence.


> Perth's metropolitan region in Western Australia has the largest percentage of underground power in the world.

I highly doubt that. Their government claims about 55% of houses has underground power. There's parts of Europe where they're easily up to 90%+. For example in the Netherlands only (part of) the high-voltage transmission network is above-ground, all house connections are underground.


Your numbers are way out, poles usually last between 25 and 70 years generally depending on what they are made from. Hardware (pins, insulators, crossarms) last at least 15 years usually, often much longer. There is certainly nothing that needs replacing every 3-5 years.

BC is currently burning to the ground. Again. I don’t think our hydro grid has failed due to forest fires, or at least not commonly. Nor is it responsible for starting them. Our territory must surely be as rugged as California’s. So maybe look North?

Don't forget the company also poisoned an entire town.[0]

[0]https://en.wikipedia.org/wiki/Hinkley,_California


I was under the impression that the higher dielectric permittivity of soil made it impractical to bury AC transmission lines. Are they switching to DC while they're at it? Is there some other solution? Are the problems caused by high permittivity overblown?

https://research.tudelft.nl/en/publications/technical-perfor... Good read if you're interested in the technicalities. They do bury high voltage (380kV) AC lines, sometimes even construct a tunnel for them, but I doubt they'll do that in this case.

Very possible, unless there's some other trick nowadays. AC does not go far underground or under water, but high voltage DC can be used for much longer distances.

The cables can be thick jacketed with a dialectrict and heavily shielded with copper tape or braid or similar material and the jacket and shielding limits the leakage but makes the cable much more expensive to manufacture and install.

I was wondering the same thing. HVDC is 'an under the radar' technology that is set to rework a lot of the grid world wide. With projects underway to send power from Australia to Singapore or Iceland to the UK it's likely to turn up in many places, even California.

I have what I think is a legitimate question. Wouldn't it be an order of magnitude cheaper just to clear all the trees 120 feet either side of the power line? Plant the cleared land to alfalfa and solicit bids from farmers to harvest it every year.

What you describe is essentially the program they had in place already. Maybe not 120 feet, but certainly some distance. They hire contract helicopters year round to survey lines, and task crews to clear brush. I live in Sonoma County, CA [1,2,3] - so we see the effort.

I think you might also be underestimating the scale of the power infrastructure in CA. The hydro etc. power generators in the north of the state are located in extremely remote areas.

My brother was a consulting engineer for PG&E in Northern CA, on a lot of their Hydropower infrastructure - most of the generation sites were only accessible by humans with helicopter flights, or 2-3 hr drives on poorly maintained roads. The transmission lines are not really accessible except by helicopter survey.

1 - https://en.wikipedia.org/wiki/LNU_Lightning_Complex_fires

2 - https://en.wikipedia.org/wiki/Glass_Fire

3 - https://en.wikipedia.org/wiki/Tubbs_Fire


it may be hard work but it's necessary.

As someone who can see the Dixie fire column daily, had family evac’d by the Bear fire last year (basically burned 100K+ acre area just SW of the Dixie), and lives 10 minutes from Paradise (the town mentioned in the article), most of the PGE right-of-ways do look like freeways now through the forest, little to no under story growth. I believe they’re limited to how far out they can go due to easements.

To add, basically the last 4 years has been the burnout of a huge swath of forest in this area between the Camp fire, Bear fire, and now the Dixie fire, not to mention the many “small” fires that were caught/didn’t get established. The majority of land between highway 32 to the La Porte/Quincy highway has burned. Don’t have a good estimate since I’m on my phone, but 100s of square miles of mostly back country forest. Both the Camp and Bear fires made 10-15 mile runs in one day, and Dixie’s put up massive pyrocumulonimbus pretty much every day this week.

Edit to add: it’s also been incredibly dry, most of June-July has been upper 90s-low 100s, with a few 110+ periods. Humidity has also been extremely low, in the afternoons 8-12%. Even overnight it only recovers up to 40-45%. Higher elevations are cooler, but not so much that it mitigates, so the forest is pretty tinderbox right now. Once it’s lit it’s hard to put out.


Plumas Forest is one of my favorite parts of CA to explore, so these fires have been difficult to watch. My favorite place to camp is this remote spot on the Feather River, luckily it hasn’t been touched by the fires yet, but it’s only a matter of time now I guess. Do you own property out there? If so, what kinds of things have you done to your property to prepare for the now seemingly inevitable?

…and? Why did you create an account 27 minutes ago to post this? Sincerely curious.

S/he has useful and relevant information to add to the discussion. Why not?

The only relevant part out of the whole multi paragraph thing was this one sentence

> most of the PGE right-of-ways do look like freeways now through the forest, little to no under story growth.

I read the whole thing waiting for a point but there wasn't one. Just a waste of time. We already know the fires are bad, and that isn't relevant to the thread anyways.


There are several (many?) posters on here who create a new throwaway account every time they say anything

Or maybe just one.

Did you have a first post too?

Not really. Trees are actually somewhat hard to burn, so most wildfires start by catching dry underbrush on fire instead. So in this case, that would just be the alfalfa.

Key to remember is that power lines can spark when they're damaged by winds (which can lead to the lines themselves being close enough to the ground for the spark to traverse to the underbrush).


This is for what utilities call "medium voltage" distribution (1KV to 35KV), not high tension towers. These are the cables you see around your neighborhood, upstream of the pole transformer. They're usually not insulated other than by airspace. Clearcutting around those would wipe out the trees in most residential areas.

The big high tension towers go through clear-cut rights of way.

The big headache is not burying cable. If there's nothing else in the ground, that's not too hard. It's working around water lines, sewer lines, gas lines, driveways, phone, data, cable TV...


That would destroy thousands of miles of wildlife habitat, and it would certainly cover some private property too.

Plus you'd have to do it regularly, not once.


Probably not. A lot of this land is in remote areas with no irrigation, steep, rocky, or otherwise difficult to manage.

No one is interested in farming alfalfa on 25% slopes with rocks 6” under any topsoil and massive trees to clear before it would even be usable.


Take the opportunity to burry empty conduit with it and lease it to telcos.

I don't know technicalities, but we have this in Wales. There are tunnels on top of which we have railways. The tunnels have power cables and fiberoptic cables. Sometimes they flood in west-mid Wales, last I know and remember was 2012 and we (Aberystwyth, Machynlleth) route internet traffic to North Wales or Ireland instead to Birmingham.

In my region, they mostly run this new, flexible plastic conduit with horizontal borers or a piercing tool. They'll dig holes several feet deep and dozens of feet apart. In one hole they start this tool and it digs its way horizontally to the next hole. From what I've seen, the conduit effortlessly follows. I'm sure geology makes a difference.

Here's a marketing video for one of these piercing tools: https://www.youtube.com/watch?time_continue=26&v=Hs3C2LMzSPg


Good idea. Maybe even get The Boring Company to make usable tunnels.

Meanwhile, in Germany, they've been burying powerlines for over a century so the entire country doesn't look like ass.

For the high voltage lines Germany is pretty much still at less than 10%.

https://www.semanticscholar.org/paper/Statistics-of-AC-Under...


Love it! My vision of the future has all power lines buried. Mostly thinking in the cities but fire prevention is a plus as well.

If anyone has any leads on startups or innovators in the tunneling space please share or each out!


Burying high voltage power lines presents several technical challenges on its own - the type and thickness of the insulation had to be able to withstand the dielectric stress which is normally solved by using enough distance between the wires themselves and the ground for the typical high voltage power line. Another problem is increased capacitive load due to the higher capacitance of the lines which causes problems/completely makes the switchgear to not be able to perform switching/breaking operations. Capacitive load then needs to be compensated to improve the networks power factor, cos phi. This is typically done by introducing expensive equipment to the network configuration like shunt reactors or static synchronous compensators. It is also typically more expensive to have and maintain a underground cable than an overhead power line

Two more issues are water tables (although those have been falling rapidly across much of California over the last few years) and seismic activity -- not just the big quake sort, but also the usual few cm a year of movement in opposite directions sort.

I suspect that this is going to be an engineering project on the scale of the mythical California high-speed rail, and with the same life cycle. PG&E especially has a track record of misusing funds for upgrades and maintenance.


> My vision of the future has all power lines buried.

Singapore already has already achieved this. It's actually quite pleasant to not have any overhead lines.

They are currently replacing the main electricity distribution cables that run under roads, and replacing them with a system that runs in tunnels 60m underground. This depth is necessary to avoid other systems like the subway(MRT) that run at shallower depths. https://www.todayonline.com/singapore/deepest-tunnels-spore-...


This is not some magical high-tech vision that only exists in Singapore. It's been this way for many decades in built-up areas of most of Western Europe -- mostly it's just overland high-voltage lines that are above ground. My grandfather used to tell the story of how his American visitors were always curious where the power in his house came from (this was probably in the 60s or 70s) and amazed when he showed them the connection in the basement. It amused him to no end.

82% of Germany's power lines are buried: https://www.iwr.de/ticker/lange-leitungen-82-prozent-der-str... (in German). This figure includes everything from low-voltage lines to houses to high-voltage distribution lines.


Many urban areas in the USA have buried power lines. I moved last year from Bellevue WA to Ballard in Seattle WA, one of the first things I noticed in my new home are all the power lines around us (they are mostly buried in Bellevue and much of the east side). Fairly sure the Bay Area is roughly the same (Palo Alto must right?), but I don’t have any anecdotes to go on.

Fascinating. Thanks for the link! I remember from a visit to Singapore a decade ago the fantastic subway and all the underground malls, but had no idea how advanced their tunnels were. Thanks!

Works for distribution networks for households in the cities, but but for high voltage transmission lines.

If you are interested in this space you can just search for “trenchless electrical conduit”. A company that makes a lot of equipment is https://www.herrenknecht.com/en/

I mean, obviously everyone desires to have the power lines buried, the issue is that it costs something like $250 billion dollars to do it in California alone.

When talking visions of the future, aim higher - get rid of the power lines altogether.

Every building should have it's entire footprint as solar panels, and enough batteries to last the night. Imagine all the money saved on power lines and maintenance of them. Especially in sunny California this is a no-brainier.


That saves no money at all, because you still need it for the cloudy day or week.

Even cloudy days produce power. Charging the car at a grid connected point instead of at home would probably shift enough usage to last a week.

Or use a generator when that happens. At my place that would be a week or two per year.


Off topic, but how do underground power lines stay cool? I always thought long distance powerlines got really hot.

Above ground "High Temperature, Low Sag" cables can reach 200°C. Underground cables can still go up to 90°C, which is still flamin' hot. They're usually buried at least 1 meter deep, which gives the heat a decent chance to dissipate. But in those areas with high chances of fires, I'd be wary all the same :-/.

Of course, the above mostly applies to high voltage & high current situations, think 150kV, 300MVA monster connections. I doubt PG&E manages 10k miles of high voltage power lines. If we're talking residential interconnections, there won't be any issues burying those.


I would have thought they'd need to put sections of cooling in, if not maybe they have some form of oil or other liquid to help dissipate the heat? I thought one of the many reasons why the UK still does overhead between chunks of the grid is for cooling and easier maintenance.

Are the associated costs passed to ratepayers at cost or is there some allowance for a positive investment return for PG&E shareholders?

In theory rate hikes have to go through California regulators but, at the same time, the company is allowed a certain rate of return.

In practice I have no clue how it works out though.


Typically in markets like CA and TX you will have a rate case go to the public utility commission. I'm more familiar with Texas' approach (it was a data source for my dissertation); the idea is to let the companies charge enough to cover reasonable costs.

Shouldn't "won't be sued for negligence" cover the investment, given that they know their equipment is a fire hazard?

No, it won't, because PG&E doesn't have the money to do this, and the company is already majority-owned by the PG&E Fire Victim Trust after emerging from bankruptcy.

There are no rich shareholders to foist the costs on. No investors are going to pay tens of billions of dollars, more profit than PG&E generated over several decades, to pay for 10% of the electric wires to be buried. If there were any investors on the hook for this, they would simply declare bankruptcy and walk away.

The only option here is that the costs are paid by ratepayers, or taxpayers. There is no other option available.


I see, thanks for explaining. That would have made for a nice addition to the article. :)

IMHO an infrastructure of this size & importance might just as well be state owned, but I guess rate hikes will also do. As long as there is some mechanism to help (yes, probably with tax money) those who might not be able to afford them...


in that case why have owners at all? it should basically be nationalized then. otherwise taxpayer paying the cost without really reaping profits (if there are/will be any)

Because government-run electric utilities are a mixed bag too. "Public" utility monopolies like PG&E are an attempt to get some of the benefits of a market system from what is fundamentally a government service. The utility can raise money from investors, who expect a modest but stable return. In theory, the profit motive gives the utility an incentive to keep costs in check.

It's far from perfect, but actually-public utilities are responsible for a lot of disasters too. It's not obvious that nationalizing PG&E would be good for anyone.


Except they have regulated profit margins - it's cost-plus. So they have an incentive to make everything as expensive as possible to maximize their take. And the CPUC rubber stamps everything the utilities ask for.

CA has some of the most expensive electricity in the nation. So it doesn't seem like the idea worked out.


California winds up being in the middle for avg money residents spend on household energy, but mostly because they don’t use AC or heat very much. https://wallethub.com/edu/energy-costs-by-state/4833

Sure, but I said most expensive electricity, not highest monthly bills.

You'll have to verify this yourself, but my understanding is that there is no clear winner on the public choice issue of public vs private electrical. There are well-run and poorly-run examples on both sides.

In PG&E's defense, it's not literally cost-plus, and the CPUC doesn't always rubber stamp everything. Imagining the government alternative, what would really be different? There will still be a big bureaucratic organization full of imperfect humans with muddy incentives and limited resources. Would PG&E be better if the board of directors was appointed by politicians instead of elected by shareholders? I doubt it.


The most expensive energy would be Alaska and Hawaii for obvious reasons. California’s rates are similar to northeastern state rates (a bit lower than their average) but is definitely high for a western state that benefits from a lot of cheap hydro.

A federal grant might work too. Wildfires on this scale affect more than just Californians.

I can’t find it now but a while back someone posted the meeting minutes from the CA PUC review of PG&E’s budget. It had stuff like “request to replace chain link fence for $175k - denied” and it was a 1,000+ page document.

PG&E has to get approval for their spend from the PUC and for any rate hikes.


Some coastal communities and islands in North Carolina took this route. In addition to beautification, they're more resilient to storms and hurricanes.

https://www.starnewsonline.com/article/NC/20071122/News/6051...


This will at least relieve PG&E from responsibility of causing wild fires.

BUT it won't stop wild fires if forest maintenance continues to remain unfunded by the California state government!

Putting lines underground definitely will also increase maintenance costs - that's why overhead lines get used in the first place. So electricity rates will remain higher as well.


I wonder if robots could help. Design some to go through the forests and mulch all the deadwood. They could work in geographic bands to create large fire breaks so the entire forest floor would not have to be mulched. There would be some environmental effects I'm sure (insects, mice, etc would get mulched as well) but that seems better than the devastation a fire causes. This seems like a limited enough problem that current technology could handle it with some human supervision in the field.

I don't understand why it is not just cheaper to clear the above ground rights of way. There are multiple reasons why transmission lines are not typically underground. The 240 from the pole to the house sure. The 240k from the plant to your local substation not so much.

Subterrainian cables are more expensive and less energy efficient than aerials. High capacitive losses, higher maintenance and installation costs, more expensive shielding and jacketing materials needed.


Burying a mile of cable takes several big machines running diesel fuel (very bad for the environment). Call it approximately 300 gallons of diesel per mile.

This plan will burn 300 * 10,000 = 3,000,000 gallons of diesel fuel.

This plan is far worse for the environment then simply doing more controlled burns to reduce fire risk.


Seems like it would be cheaper to just monitor transmission lines more closely. Detect sparks and shut off the affected lines before they have time to ignite brush. Maybe a job for cameras and machine learning?

I assume the liability costs far outweigh costs to upgrade/operational costs. Likely will ratebase a bunch of this work as well. That and they might just get kicked of business by the CPUC if they didn't manage their risk profiles more effectively.

California might need to limit the extent to which it:

- lets environmentalists file viable injunctions against logging on federal lands

- prohibits or greatly limits grazing


It’s almost as if there needs to be some form of tax on carbon emissions to help pay for mitigation of the effects of climate change.

Almost everything is in the ground in the Netherlands.

So what burial equipment or service providers do we buy calls on?

...again.

Are we just going to ignore the fact wildfires are a natural occurrence and the entire reason we're experiencing catastrophic wildfires now is from decades of obsessively preventing every fire? Not saying we should go around creating fire hazards but compared to efforts to mitigate fuel overload by thinning and controlled burns, burying some power lines is a drop in a bucket barely worth mentioning. Utility corporations don't do things out of the kindness of their hearts. Guarantee PG&E are doing this for some kind of maintenance, tax, social, or litigious incentive. It certainly has more to do with the bottom line and their PR department is trying to spin it as some altruistic BS. Why are we jerking them off over this when if California's forests were properly managed a small risk of fire wouldn't be a concern, and in many cases may be a boon to the ecosystem?

Piss take, I know, but nature is pressing her reset button and it's our fault. Let's not act like PG&E has anything to do with it.


Exactly.

This is good for PG&E because it can't be blamed for wild fires. The wild fires will still continue to happen only now it will be the set remaining causes:

(lightning, car exhaust systems, campers' fires, arsonists, ...)

It's NOT primarily or even remotely Global Warming however. California has a fundamentally dry climate the intrinsically assures wild fires will occur. Expanding in wild fire prone areas is a direct result of real estate booms and costs, which are primarily high for artificial human reasons such as NIMBYism, greed, real estate as investment, etc.


Fire is such an ancient and normal part of California that redwoods have evolved to be fireproof, with many local trees and plants having seeds that require fire for germination. [1]

[1] https://www.nationalforests.org/our-forests/your-national-fo...


> It's NOT primarily or even remotely Global Warming however. California has a fundamentally dry climate the intrinsically assures wild fires will occur.

Global warming is an amplifier for wildfire risk, not a cause. The increasing length of the dry season under the influence of global warming has made these sorts of fires that much more likely.


> It's NOT primarily or even remotely Global Warming however.

That's for sure an opinion I would love to have more information on.


Native Americans did controlled burns to prevent catastrophic wildfires and encourage new plant growth. Fires in California have been an issue well before man made pollution became a thing.

It probably has more to do with things like this: (analysis of Camp Fire) https://twitter.com/TubeTimeUS/status/1306359385656946688

We detached this subthread from https://news.ycombinator.com/item?id=27918330. Please don't reply to specific comments with generic posts that aren't really replies—it dilutes and distracts from whatever the parent comment was about. Just make a top level comment instead.

"Great they are doing this" but passing the cost on to their customers, who will foot the bill for it. So maybe you should thank the PG&E customers who will end up paying for it.

> "Great they are doing this" but passing the cost on to their customers, who will foot the bill for it

It's probably worth it to the customers, too. So much so that PG&E's survival is in question if they don't start taking fire safety super-seriously.


Most PG&E customers don't live in fire zones, though.

I would say most of them do. Look at a satellite map of the Bay Area. Most cities are built right up against forested areas that I would call fire zones. The Santa Rosa fire and the Oakland hills fire were quite large and burned thousands of homes in urban areas, but started in forested areas nearby. Saying people should stop building in the forest and stay in cities will prevent the problems when the forests burn forget that most of the cities in California are next to forests that burn (Bay Area, Los Angeles, etc.). I guess we could clear cut those.

Many live downwind of the smoke, though.

The customers use the electricity they generate. Who else would pay for it?

I’m not sure I get your point.

We detached this subthread from https://news.ycombinator.com/item?id=27918330.

Or charge the PG&E customers for the various forest fires their electrical consumption has caused

We are beginning to see the real costs of Global warming, the exact thing activists were bull horning about and the same thing corporations were denying.

"Eschew flamebait. Avoid generic tangents."

https://news.ycombinator.com/newsguidelines.html


https://fas.org/sgp/crs/misc/IF10244.pdf

https://www.fs.fed.us/psw/publications/mckelvey/mckelvey3.pd...

Look at figure 41.2 in the second pdf.

Wildfires are not historically worse than they have ever been. You're falling victim to recency bias. You can absolutely credibly claim that wildfires are not more or less common than they have been historically, it's all in the noise. The activists have not been proven right, and the corporations have not been proven wrong.

edit: note that I'm not denying the existence of climate change nor denying that it may eventually have an effect on forest fires. I'm merely claiming that the data does not support what you're saying.


Even a cursory reading of both the documents that you present shows the following points.

1. While the number of fires have reduced, the total area consumed by fires is still rising. 2. The average area fired up is increasing at an alarming rate (Fig. 41.3, still upto 2000 only.) Refer the first document. Fig. I, the trend in forest fire area affected is increasing, from about 2 million acres in 1990 to about 10 million acres in 2020.

Also, fig 41.2 is data from 1908 to 1988.

Edit : Please see the 10 million acre figure in the first PDF. Think of the enormous costs related to containing the fire. The data is not in isolation. Fire-fighting techniques and costs have to be taken into account.

https://www.fs.usda.gov/sites/default/files/2015-Fire-Budget...

This document from US govt explains how much they are spending fighting forest fires. Budget for wildfire management rose from 15% in 1995 to about 52% in 2015, with more increase projected upto 2025.

Also, the cost of wildfires is enormous.

https://www.nfpa.org/News-and-Research/Publications-and-medi...


I’m going to assume good faith, but Figure 41.2 only has data through 1992 (the paper is from 1995). 30-ish years of hotter, drier seasons might change that picture.

In fact, Figure 1 in your first pdf says just that: the “count” of fires is similar to that in 1991, but the area burned has more than tripled.

That is what people are talking about: the past few years have had mega fires and “complex fires”.


On top of the other responses, I don't think the two sources use comparable data to begin with. The first source says that there were ~2m acres burned in both of 1991 and 1992, whereas the latter peaks at 100 k/ha, which converts to about 240k acres, nowhere near 2m.

The second document is only related to forest service. Does not include other types of lands.

Mostly we're seeing the costs of not managing forest in a sustainable manner. But, yes, climate change is making that stupidity worse.

The costs of not managing forests well, the costs of building cities so close to the ocean, the cost of growing food in what is now a desert, the cost of having population centers in areas which reach 50 degrees in the summer, global warming is going to “uncover” quite a lot of costs.


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