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.
Those of us in NZ would like to point out that access to the ocean does not necessarily mean shipping is cheap.
Does that only apply as long as the person isn't pregnant, or possibly cannot be pregnant?
Two religions is not more statistically significant than one.
Referring to yourself in the third person and acting like this comes off as extremely condescending.
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.
Indeed.
In addition, there's a lot of consumption that was non-electric (e.g. transport, heating) that is moving to electric. Most of the increased grid consumption is not new consumption, it's consumption that was previously direct fossil fuels.
The exception is basically bitcoin and AI, plus electrification of underdeveloped areas.
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.
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.