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Comment by breck | Hacker News Reader

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!

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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-...

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

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!

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.

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.

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

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.

https://www.boringcompany.com/

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