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Comment by whack | Hacker News Reader

You're asking the wrong question. There are over a hundred million Americans who commute long distances in their car. Mostly because they live/work in areas that aren't dense enough to have good last-mile public transit, and they don't want to deal with transfers. You can lecture them all you want, but ultimately, these people aren't going to downgrade their lifestyle just to fit your ideas of engineering efficiency.

The real question is: is this new solution more efficient than the current alternative of driving on the highway?

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If places aren't dense enough to support mass transit, they are certainly not dense enough to financially support car-trains tunnels. The depicted tunnels have the same costs as building subways, and I imagine similar maintenance costs. On the other hand, they can only serve a fraction of the riders a traditional subway can, which means the cost per rider is huge. Not to mention it still requires owning a car, so the traditional capital and insurance savings from mass transit don't apply.

But to answer your question: maybe, but it doesn't matter. American cities are already bankrupting themselves in road maintenance. Adding a series of super car tunnels for an efficiency benefit? Out of the question.

This solves the last Mile problem

So do big parking garages at suburban train stations.

So does having train stations every few corners. The reason we don't have that now is cost, which is the same reason we won't have car-train tunnels.

Obviously having a network of underground express tunnels for cars would be amazing. It's just economic nonsense when municipal governments are racking up huge debts in normal, above ground road maintenance. If it's not publically subsidized, drivers will be exposed to the true cost, which will be enormous. That high cost cannot be supported will prevent mass adoption.

Why does everyone lack imagination on this topic?

Problem: if you drive to the subway, then take the subway, then you have two problems: where do you park your car, and how do you get to your destination once you get off the subway if it's not walking distance?

Currently - people just drive. And the surface streets get progressively more crowded. We could drill more regular roadways - but it's notable that one reason we don't is controlling emissions and safety is difficult with human drivers.

So, taking that back to the video: replace the subway with general purpose transport stations that provide a mix of subway-like transport of passengers, or entire vehicles, powered electrically.

No vehicle emissions (huge problem with tunnels) and no endpoint transport issues - the subway becomes an extension of the road network, and if it's cheap enough to do, hopefully a very scalable one.

> We could drill more regular roadways - but it's notable that one reason we don't is controlling emissions and safety is difficult with human drivers.

Also cost. Drilling car tunnels is more expensive per passenger served than a mass transit system

> if it's cheap enough to do, hopefully a very scalable one

That's a big unproven if, and a hope that's almost out of a science fiction novel. If Musk has ideas about how to solve those problems, let's hear them.

We already understand that tunnels with electric cars would be great. Everything we do has a cost and if we're going to work together on something as a society, let's do something that benefits more of us than luxury car owners

The two problems you discuss are both easier to solve than LONG DISTANCE BORED TUNNELS.

Solution for problem 1: Park and Ride. Giant multi story parking lots. Cheaper to build even underground than the tunnel Solution for problem 2: Local transit like Tram, bus, or bikeshare.

I think a far better solution to #2 is taxis or other on-demand transportation that can take you directly from subway stops to your destination. Trams and buses have the same last-mile problem as subways, but to a lesser extent, and often require passengers to wait longer for the next tram/bus. Bicycles have practicality limitations such as luggage storage, cold weather, and physical ability.

I understand those benefits, and think they are marvelous, but also very expensive.

American cities are already spending more than they can afford on road maintenance. Are these underground trains going to be cheaper than above ground roads? Public money for this doesn't seem all that likely.

Here in Tokyo, the Yamanote above ground train serves a million riders daily. Costs a couple dollars to go 10km. The boring concept looks much more expensive than that, as it is underground, but those costs are spread out over many fewer people. Private money seems hard, too.

> Why does everyone lack imagination on this topic?

You are right, I imagine that we should just have teleporting gates!

> if you drive to the subway

How about not driving to the subway? how about having local buses or that can take you there?

> where do you park your car

Car parks next to the station?

> how do you get to your destination once you get off the subway if it's not walking distance?

Buses or trams.

> Currently - people just drive.

Not everywhere, look at London for example.

> We could drill more regular roadways

No we can't, tunnels are expensive and bring a whole new set of problems like how do you handle an accident, how do you get to the surface etc.

> subway-like transport of passengers, or entire vehicles

That is horribly inefficient in terms of space and weight, average car weight is ~2 tons.

> powered electrically

Having it electrically powered does not mean that it's clean energy.

> Mostly because they live/work in areas that aren't dense enough to have good last-mile public transit, and they don't want to deal with transfers.

Well, suburbanization was a totally dumbass move. Maybe instead of building tunnels, we could be rebuilding cities. We could be designing them to be attractive enough that people would want to live there.

You'd have to get the government to stop building roads...

which of course is seems crazy to most people. But the consequences are all around us.

Yeah. Going from rail to roads was another dumbass move.

When a city in America is destroyed by a nuclear explosion, Americans will re-learn why suburbia was so popular. Hopefully this won't happen for a long time and we will have a good stretch of city living. I love cities, but having millions of people concentrated enough to be killed by a single device; this is very different world than the one humans evolved in.

Sure, maybe that was part of it. Interstates were, for sure. But then, the Soviets were building huge warheads, which could take out metro regions.

That's such a terrible reason not to live in a city. I don't see how it is significantly more likely for only a single incident like that to happen. If we really have a catasophre or act of war it will likely effect larger regions than just a single city.

Are you serious?

> : is this new solution more efficient than the current alternative of driving on the highway?

No.

Because - the exurbs and beyond simply don't have the density numbers to make this kind of investment pencil out without something like a 1000x class drop in costs, which would be wildly optimistic for physical equipment cost savings. Some suburbs might be able to handle it; Bellevue in the Puget Sound comes to mind immediately, but it's only a suburb in the context of Seattle; it'd be a major city in its own right in most of the US.

Further, you're not even getting to the fun part of driving a car - the wind, the sights, the open road. You've got a dang tunnel there. I'd get mildly claustrophobic and probably nauseous: subways already do that to me a little bit.

It's probably much more effective public policy at the federal level to focus on densifying American cities and reversing sprawl: this generates a nice sequence of network effects related to funding and infrastructural improvements. Among those would, eventually, be the demand for nice buses and nice trains with a regular security presence.

>Further, you're not even getting to the fun part of driving a car - the wind, the sights, the open road. You've got a dang tunnel there. I'd get mildly claustrophobic and probably nauseous: subways already do that to me a little bit.

I sure do love the wind, the sights, the open road of stop and go traffic every day.

Avoiding driving for ours in congestion would sound like an upgrade to me...

if you'd create 124mph transportation from 20-60 miles outside and through the city into the city, you wouldn't need to drive into the city. Most commuter trains average less than 50 so it's worth trying to drive. The average speed of the NYC subway is less than 35 mph. Light Rail?

Low-speed maglev: https://www.youtube.com/watch?v=c8SqDVUdMtY

What about waiting time between transfers? You need a certain population density to have almost continuous trains. In Bay Area, you have to wait an hour between Caltrains unless it is rush hour. Caltrains could go 500mph, I would still drive to avoid the wait between trains.

Demand for Caltrain is standing room only during rush hour, with 33% of traffic living in Palo Alto and working in SF.

Caltrain has two primary constraints, neither population-linked: diesel trains accelerate badly, and freight track scheduling.

Diesel trains are theoretically being swapped for electric, which will permit the trains to stop and start more efficiently. They predict one additional train during peak rush hour per day for this improvement, iirc.

Freight traffic consumes a fixed amount of rail time, focused primarily on the "one hour between" segments of the schedule. Increasing frequency can only occur within existing scheduled route times, and cannot disrupt that freight traffic.

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