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Comment by WalterBright | Hacker News Reader

Here in the Seattle area, we regularly have a big blow which knocks trees onto the power lines and vast portions of the power grid go down. While it happens to some extent every year, about once a decade it's a several day outage, even in the city. The last time it was 10 days. The power cables were down for miles everywhere.

And yet, everything gets rebuilt in place, the same way, the same risks. No engineering improvements. No buried cables (which do just fine in storms).

Most everyone in my neighborhood has some sort of generator, and we're well inside the dense part of the city.

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Buried cables tend to have a higher lifetime cost, which is one reason why Seattle has stuck with aerial cables in so many neighborhoods.

West Seattle neighborhoods have more buried cables than most, and they're facing some very expensive reliability issues due to IIRC dielectric breakdown.

If Seattle wanted to squeeze better reliability out of their aerial transmission systems, they could move to a four-year tree clearance pruning cycle, like Portland. Last I heard, we're still on a five year cycle and every time changing it comes up, it's seen as cost prohibitive.

We get the reliability we're willing to pay for.

Is there any reason why Europe can do buried cables just fine (and has been for a good few decades), but the US can't? As I understand even new neighbourhoods in the US often have overhead cables.

I live in Europe, and in general we don't distrust the state, and we don't want to pay less taxes (we would like more efficiency managing them, though).

Interesting, somehow I never thought of that. Lowering taxes is just not a major talking point in European politics except maybe for certain types of taxes, or distributing them differently, but there are no big divides on this.

The situation is highly regional. Walter's experience is specific to Seattle, but he's right that each region has its own infrastructure problems. Denver metro area (my neck of the woods) has mostly buried power, but a long-term fresh water problem.

Buried infrastructure also tends to be down for longer. Above ground lines go down more often. But they're easier to fix when they do; fixing buried lines can be a nightmare.

As an example, a mall near me was without power for weeks after flooding destroyed some underground electric infrastructure. The flooding didn't even do any real harm to the mall! They just got unlucky: underground lines and other equipment that should be waterproof weren't, and they shorted out in such a way that a bunch of stuff had to be dug up and replaced.

Also anecdotal here but I can't remember the last time power was down for a long time where I live in Belgium.

If I hear about issues it's generally extremely local or an issue with power generation (we're predicted to have more issues in the future due to our gov being idiots void of long term thinking when it came to replacing old nuclear plants)

So all in all I haven't experienced this being down longer issue (and yes flooding shouldn't be able to destroy underground lines and such.)

In 2019, some contractor got lucky while doing drilling works and scored a hit on both the main cable and the backup cable connecting the neighborhood of Berlin-Köpenick to the grid - severing each of the three phases in both cables. Establishing the construction site, digging the hole and fixing the two 110KV cables took a mere 31 hours - and that includes 6 hours of setting time for the couplings used. This was pretty much the worst case scenario that could have happened. It's possible to maintain good uptime with buried infrastructure, as with most things it's a matter of spending the money to do so.

It seems we are generally unwilling to pay for a higher level of availability-- that the current level is generally speaking good enough. We prosthelytize that we must do better, but voting with our pocketbooks is another matter.

Usually the fallen trees are removed, aren't they? Isn't that an improvement?

The next year another tree falls. It's a continuous process. Trees grow faster than one thinks - in 25 years it's big enough to threaten the lines.

Which is why you spend a lot of time maintaining the ”power cable streets”, whatever that is called in American.

See https://www.slu.se/globalassets/ew/org/centrb/cbm/bilder/for...

using a glorious flying saw attached to a helicopter. https://www.youtube.com/watch?v=3MpD-sootTs (classic german kids tv show)

I'd have loved to be in that design meeting: "Look, we could just build a huge saw and attach it to a helo." - "Ok, sounds fine, what could possibly go wrong?

Underground costs about 10x as much as overhead.

Just in the time I've been living in this neighborhood, they've restrung the overhead wires, with new poles, more than 10 times.

The street I live on has underground cables (the overhead lines go underground for my street) has never had a cable failure, though fallen trees have blocked the road. That latter gets straightened out by the neighbors, as many have chainsaws and always look for an opportunity to use them :-)

(Seattle neighborhoods have lots of trees!)

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