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This Boring Tunnel is all hype so far. The demo tunnel doesn't look to have sufficient ventilation or emergency exits in case of fire, car crash, etc. They ha

by pdq 7y ago

This Boring Tunnel is all hype so far. The demo tunnel doesn't look to have sufficient ventilation or emergency exits in case of fire, car crash, etc. They haven't addressed the ingress and egress congestion problems into and out of the tunnel. How can a single elevator go up/down to handle 1000+ cars per hour (4400 passengers per hour)? Basic math gives you 3.6 seconds for the elevator to go down, wait for the car to offramp, go back up, and wait for the next car to onramp. These are some of the many reasons tunnels and subways get expensive. You can't just build a basic tunnel rigged with cars and say "problem solved" at 1/10th the cost.

WhompingWindows 7y ago
It's mostly hype yes, what do you expect from a startup? The strongest premise is the tunnel diameter is smaller, therefore quicker and cheaper to build. There may be efficiencies to be gained through improved engineering of tunneling machines as well, given SpaceX and Tesla's innovations. Yes, there are many problems left, however every start-up faces a number of problems. They're basically just lining up to build an MVP, or perhaps that was the previous tunnel and LVCC is the beta version. In either case, they have a CEO famous for his marketing and overly optimistic promises. If this wasn't an Elon Musk venture, I doubt it'd be getting over-hyped and blasted as much as it is.
- HillRat 7y ago
  The price tag for the tunnel is pretty much what you’d expect at the low end of civil engineering costs, so there’s no room in the pricing if things start to go south. Musk’s entire premise is that there are magical inefficiencies in the commercial tunnel boring machines he’s purchased, and he assumes that spacecraft and automotive engineering expertise is sufficiently transferable to uncover those opportunities and redesign a considerably more efficient and cheaper machine. Oh, and using commercial automobiles will be faster, cheaper, and more pax-intensive than light rail solutions. I’m … skeptical. Let’s go with “skeptical” on this one.
  - jcranmer 7y ago
    Based on my ballpark guesses at the cost of the tunnel, I would be surprised if The Boring Company actually made any money on this. They're liable for all cost overruns, and they have to bear the costs of developing the custom Tesla car manufacturing and safety qualification themselves. The most galling part to me is that I can't see how they make the mandated 4400 people/hr limit. That requires 26 second headways between vehicles (assuming that 4400 people/hr is a bidirectional capacity, not unidirectional), and I don't see them getting station dwell times low enough to permit those headways--airport people movers usually run around 30-45 second dwell times.
    - neetdeth 7y ago
      Wouldn't the obvious solution be to multiplex cars at each station? They could have twenty Teslas at each location for passenger pickup/drop-off, only entering the launch queue when all occupants are seated and restrained.
    - vidarh 7y ago
      You're thinking in train terms. There's nowhere near 26 second headway between vehicles in busy tunnels near me - cars enter and exit the road from multiple sides before entering and the headway in the tunnel is much shorter. 30-45 second headway makes sense when your station stops blocks the entrance to the tunnel, which is the norm for rail systems, but not for car tunnels.
ryantgtg 7y ago
Unless I'm misunderstanding you, there isn't a offramp/onramp in the latest design scheme. When Boring Company first unveiled the design, it had elevators that moved vehicles from grade-level to the tunnel. The vehicles then locked into a track. Then after reaching an "exit" the vehicle is brought back to the surface so the driver can continue the journey within that same vehicle. But they recently scrapped all that. In the current design, there is no locked track and the vehicles never leave the tunnel. This ensures that the tunnels only function with a proprietary vehicle. There still might be some human ingress/egress issues to resolve.
- michaelleslie 7y ago
  Sounds like a less-scalable metro system, a technology that predates this "innovation" by a century or so.
  - losteric 7y ago
    Musk wants to re-engineering both tunnel boring and how we use tunnels - the latter may not pan out but the former is useful regardless of what gets run through the tunnel.
    - jcranmer 7y ago
      Not necessarily. The key cost savings that Musk envisions boils down to "build tunnels that are too small to put existing rolling stock in," which means that if the proposed personal rapid transit system turns out to be like every other PRT system and not work well, you're left with a tunnel that is too small to be useful for anything else.
      - Retric 7y ago
        Making an existing tunnel wider is vastly cheaper than building an equivalent tunnel from scratch. Simply knowing the soil composition makes a huge difference. In hard rock you can use drilling and blasting across long sections rather than just the leading edge. Alternatively, a TBM needs to remove significantly less material.
deleted 7y ago
[deleted]
avar 7y ago
> ingress and egress congestion problems into and out of the tunnel[..] They posted a video 2 years ago that has 6 million views that shows how this works in the first 30 seconds. It was all over the news when it was posted: https://www.youtube.com/watch?v=u5V_VzRrSBI#t=0m13s https://www.youtube.com/watch?v=u5V_VzRrSBI#t=0m13s It'll work on the basis of tunnel on-ramps merging into the main tunnel, just like highways or train stations.
ben509 7y ago
From what I saw, the hyped Boring tunnel cost savings he demoed were by comparing the cost of the tunnel he had built to the cost of a complete station. Comparing apples to apples, it's competitive, and that's an achievement in itself, but they haven't proven anything like the savings he claimed. That's a recurring theme with Musk's hype. It's great that he's taking a fresh look at these things, and in some cases he's found some genuine efficiencies, but the expectations he puts out is that the rest of industry is locked down into hopelessly obsolete and inefficient methods. That's just not true, but it's a very appealing story.
HALtheWise 7y ago
It is totally fair that what they have shown isn't ready to change the world, but at least give them credit for thinking about those problems and having innovative solutions. Electric motors vastly reduce ventilation requirements, autonomous vehicles under the control of the central system make it possible to evacuate most riders rapidly in the event of an emergency without leaving the cars, and having small vehicles going straight to your destination means there can be many more stations, decreasing the traffic at each one. All of these are fundamentally new technologies that aren't part of traditional subways, and if they can get them all to work, it will be a system with new and novel capabilities.

by pdq 7y ago

WhompingWindows 7y ago

It's mostly hype yes, what do you expect from a startup? The strongest premise is the tunnel diameter is smaller, therefore quicker and cheaper to build. There may be efficiencies to be gained through improved engineering of tunneling machines as well, given SpaceX and Tesla's innovations. Yes, there are many problems left, however every start-up faces a number of problems. They're basically just lining up to build an MVP, or perhaps that was the previous tunnel and LVCC is the beta version. In either case, they have a CEO famous for his marketing and overly optimistic promises. If this wasn't an Elon Musk venture, I doubt it'd be getting over-hyped and blasted as much as it is.

HillRat 7y ago
The price tag for the tunnel is pretty much what you’d expect at the low end of civil engineering costs, so there’s no room in the pricing if things start to go south. Musk’s entire premise is that there are magical inefficiencies in the commercial tunnel boring machines he’s purchased, and he assumes that spacecraft and automotive engineering expertise is sufficiently transferable to uncover those opportunities and redesign a considerably more efficient and cheaper machine. Oh, and using commercial automobiles will be faster, cheaper, and more pax-intensive than light rail solutions. I’m … skeptical. Let’s go with “skeptical” on this one.
- jcranmer 7y ago
  Based on my ballpark guesses at the cost of the tunnel, I would be surprised if The Boring Company actually made any money on this. They're liable for all cost overruns, and they have to bear the costs of developing the custom Tesla car manufacturing and safety qualification themselves. The most galling part to me is that I can't see how they make the mandated 4400 people/hr limit. That requires 26 second headways between vehicles (assuming that 4400 people/hr is a bidirectional capacity, not unidirectional), and I don't see them getting station dwell times low enough to permit those headways--airport people movers usually run around 30-45 second dwell times.
  - neetdeth 7y ago
    Wouldn't the obvious solution be to multiplex cars at each station? They could have twenty Teslas at each location for passenger pickup/drop-off, only entering the launch queue when all occupants are seated and restrained.
  - vidarh 7y ago
    You're thinking in train terms. There's nowhere near 26 second headway between vehicles in busy tunnels near me - cars enter and exit the road from multiple sides before entering and the headway in the tunnel is much shorter. 30-45 second headway makes sense when your station stops blocks the entrance to the tunnel, which is the norm for rail systems, but not for car tunnels.

ryantgtg 7y ago

Unless I'm misunderstanding you, there isn't a offramp/onramp in the latest design scheme. When Boring Company first unveiled the design, it had elevators that moved vehicles from grade-level to the tunnel. The vehicles then locked into a track. Then after reaching an "exit" the vehicle is brought back to the surface so the driver can continue the journey within that same vehicle. But they recently scrapped all that. In the current design, there is no locked track and the vehicles never leave the tunnel. This ensures that the tunnels only function with a proprietary vehicle. There still might be some human ingress/egress issues to resolve.

michaelleslie 7y ago
Sounds like a less-scalable metro system, a technology that predates this "innovation" by a century or so.
- losteric 7y ago
  Musk wants to re-engineering both tunnel boring and how we use tunnels - the latter may not pan out but the former is useful regardless of what gets run through the tunnel.
  - jcranmer 7y ago
    Not necessarily. The key cost savings that Musk envisions boils down to "build tunnels that are too small to put existing rolling stock in," which means that if the proposed personal rapid transit system turns out to be like every other PRT system and not work well, you're left with a tunnel that is too small to be useful for anything else.
    - Retric 7y ago
      Making an existing tunnel wider is vastly cheaper than building an equivalent tunnel from scratch. Simply knowing the soil composition makes a huge difference. In hard rock you can use drilling and blasting across long sections rather than just the leading edge. Alternatively, a TBM needs to remove significantly less material.

deleted 7y ago

[deleted]

avar 7y ago

> ingress and egress congestion problems into and out of the tunnel[..] They posted a video 2 years ago that has 6 million views that shows how this works in the first 30 seconds. It was all over the news when it was posted: https://www.youtube.com/watch?v=u5V_VzRrSBI#t=0m13s https://www.youtube.com/watch?v=u5V_VzRrSBI#t=0m13s It'll work on the basis of tunnel on-ramps merging into the main tunnel, just like highways or train stations.

ben509 7y ago

From what I saw, the hyped Boring tunnel cost savings he demoed were by comparing the cost of the tunnel he had built to the cost of a complete station. Comparing apples to apples, it's competitive, and that's an achievement in itself, but they haven't proven anything like the savings he claimed. That's a recurring theme with Musk's hype. It's great that he's taking a fresh look at these things, and in some cases he's found some genuine efficiencies, but the expectations he puts out is that the rest of industry is locked down into hopelessly obsolete and inefficient methods. That's just not true, but it's a very appealing story.

HALtheWise 7y ago

It is totally fair that what they have shown isn't ready to change the world, but at least give them credit for thinking about those problems and having innovative solutions. Electric motors vastly reduce ventilation requirements, autonomous vehicles under the control of the central system make it possible to evacuate most riders rapidly in the event of an emergency without leaving the cars, and having small vehicles going straight to your destination means there can be many more stations, decreasing the traffic at each one. All of these are fundamentally new technologies that aren't part of traditional subways, and if they can get them all to work, it will be a system with new and novel capabilities.