Fibre needs bigger bend radii proportional to the cable size, but they’re still rarely over 15mm diameter cables so you can bend them in like 150mm.

Once you start getting to 11kV MV cables, they do like 2m bend radii.

Yeah, directional thrusting is a thing. It was used a lot when contractors were installing NZ’s new fibre network about a decade ago. I don’t think it’s in as widespread usage for power because power cables tend to have much wider bending radii.

Regular trains don’t run underground. Lots of opencast mines exist .

Basically all mines have an above ground terminal where whatever you mined is unloaded from your underground trains, lifts, haul trucks or whatever else onto storage piles, then loaded onto the actual long distance trains.

If the mine entry is up a mountain, then the trip down from that point will be a net energy producer regardless of anything else.

I wouldn’t be surprised if there are electrified railway lines doing the same. Regenerate large amounts of energy into the grid while descending loaded; consume a relatively small amount of energy to haul the empty train back uphill.

If you’re thinking of that CGI crane lifting concrete blocks, it’s unfortunately a really bad idea.

Pumped hydro stores energy by lifting weight uphill, instead. Water is basically the cheapest thing you can get per tonne, and is easy to contain and move.

To store useful amounts of energy using gravity, you need pretty large elevation differences and millions of tonnes of mass to move.

I expect structural life of the tunnels isn’t much longer than the services within them, especially with roads above.

Boring through rock is super slow and expensive, plus now your tunnel needs to be big enough to walk & run machines through, and needs aircon to keep it cool. It is done, but usually only in CBD areas where you need lots of cables and room for future expansion. Google ‘cable tunnel’ and you’ll find lots of examples. Trenching machines go through very expensive consumable digging teeth whereas bucket trucks are just a fancy forklift, burning fuel and needing hydraulic & engine maintenance.

With high voltage cables, the (really thick) insulation gets really expensive, plus you need more conductor (copper/aluminium) because the insulation needs to stay cool. Aerial lines are directly air cooled (better cooling), and can run hotter, because the limit is the metal getting too hot and sagging, not the plastic degrading. Glass insulators are only needed at every tower and can be easily replaced.

Because keeping the conductor small is important, you need to use expensive copper rather than cheap aluminium for cables.

You also need regular joints which are very labour intensive, because they have to be perfect and you can’t make a cable the full length because you can’t ship a drum that big.

If a cable fails, fixing it is much harder than fixing an aerial issue. There was a cable fault in LA in 1989 that took 8 months of round-the-clock work to fix. When a tower falls over (usually because of slope failure or undermining), temporary structures are usually up in a couple of days.

Digging trenches under roads is much more invasive than pulling cables over roads, and rivers are even worse to deal with. It’s very common for underground cables to be converted to overhead when they cross a river before heading back underground.

The Western HVDC Link between Scotland and England was built as an undersea cable because it’s so hard to get planning permission and land rights to do major projects in the UK, as High Speed 2 found out.

Yeah, we have lots of underground services here in NZ. It’s when you start getting to low population densities that you start having trouble doing it.

Plenty of cities have ‘steam tunnels’ used for far more than just steam pipes, and sometimes no steam in there at all. It’s an awesome solution where you have reasonable density, and especially for within a facility/campus.

I don’t think you’re going to see it happen in surburban streets. It’s the tyranny of the car.

I can’t find the exact shot, but I used to have a picture of the 220kV lines parallel to the Desert Road as my desktop background. Something like this:https://johnmathews.smugmug.com/Nov-18-Desert-Road-North-Island/i-CkSm5tK

Underground works well for greenfields construction, where you can map everything out ahead of time and don’t have to deal with existing underground services.

It’s manageable on low-density streets where its really only three waters and maybe some telephone lines.

It’s a nightmare to underground existing infrastructure in dense environments. Underground is already full of three generations of critical comms, corroding gas, water, HV lines that will fail if you look at them wrong, and if you’re really unlucky, steam pipes too.

Still about a 10x cost difference, plus (particularly on transmission lines) there’s issues with extra capacitive loading.

As in coal-powered steam trains? There’s a moderate number in tourist service around the world.

Diesel or electric trains carrying coal are still very common.

I feel dumber having read that.

Banning a whole country because you disliked a company?

Dealing with stuff that’s ‘almost working’ is often harder than starting from scratch; ask any tradesperson.

They also apparently cannot get their heads around the fact that people might give you a discount if you advertise their brand. Ad-supported pricing has been around for a long time; it’s not some voodoo.

Until the day comes that I get a letter in the mail from the government saying, “Here’s how much you paid in taxes, if you’re cool with that then please disregard”, I will not be satisfied.

NZ does that. More accurately, they email you to tell you that there’s a letter available online - I don’t think they send physical mail by default.

Then they pay any refund straight into your nominated bank account.

Any hard drive can fail at any time with or without warning. Worrying too much about individual drive families’ reliability isn’t worth it if you’re dealing with few drives. Worry instead about backups and recovery plans in case it does happen.

Bigger drives have significantly lower power usage per TB, and cost per TB is lowest around 12-16TB. Bigger drives also lets you fit more storage in a given box. Drives 12TB and up are all currently helium filled which run significantly cooler.

Two preferred options in the data hoarder communities are shucking (external drives are cheaper than internal, so remove the case) and buying refurb or grey market drives from vendors like Server Supply or Water Panther. In both cases, the savings are usually big enough that you can simply buy an extra drive to make up for any loss of warranty.

Under US$15/TB is typically a ‘good’ price.

For media serving and deep storage, HDDs are still fine and cheap. For general file storage, consider SSDs to improve IOPS.

I don’t remember if they fully closed the loopholes, but there are inputs that programs cannot catch unless you actually replace the OS.

You don’t normally need to specify that the sides are parallel if you specify four right angles.

Here in NZ they do a factory reset on your calculator at the start of every exam.

When you download a torrent, you’re downloading it from someone else’s computer. That ‘someone else’ is usually an individual, not some file sharing site with redundant servers.

When you download a torrent, someone had to send it. It’s a small cost for individual torrents, but they had to pay for energy, internet connection, hard drives etc. If more people seed the torrent, you get a small bit of it from each seed, spreading the burden.

If no-one with the torrent has their computer on and seeding it, you cannot download the file, because there is no-one to download it from. If there are several seeds with the torrent, then you can still download it even if one or more seeds turn the computer off at night, delete the file, or are overloaded.