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The Boring Company FAQ

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Re: The Boring Company FAQ

#201

Post by ktta »

josephpmay wrote: post #69
so33 wrote: post #45

Earlier quoted context omitted.

But there is still a last mile problem, you have to enter and exit out of the tunnels. That's the last mile. Or do you suggest that tunnel building will become so viable from an economic and engineering standpoint that everyone will have an entry point in their garage? > This freedom-supporting tech also thwarts the tyranny inherent in public transit (schedules, robbing your life with all the waiting, limited load ca…

No last mile problem, as in your autonomous vehicle will drive the last mile

The last mile problem isn't about difficulty to drive, it is about congestion. Tunnels, however long they maybe to take advantage of the speed, must end. At the endpoint is where the problems start with trying to accommodate capacity everyone thinks it'll achieve.

Re: The Boring Company FAQ

#202

Post by gosheroo »

resf wrote: post #164
gosheroo wrote: post #64

Earlier quoted context omitted.

Using the grid there must be a lot of transformers and cabling involved. Plus with massive amounts of power in situ one might be able to process the waste rock differently (e.g. if it's looser material with fissures, compress it against the sides of the tunnel or perhaps even melt it rather than removing it. Admittedly I'm rather ignorant of soil and rock physics.)

Nuclear reactors require a heatsink, usually a large amount of water. If you put a nuclear reactor underground, you have to pump water back up. This takes a lot of energy. Whereas, electrical energy travelling through cables is not affected by gravity.

What if you used the heat to melt rock?

Re: The Boring Company FAQ

#203

Post by Confusion »

josephg wrote: post #148
erentz wrote: post #74

Earlier quoted context omitted.

Yeah this is all very odd and everyone is lapping it up. He claims to want to reduce tunneling costs by a factor of 10, but starts by quoting a very high benchmark of $1 billion per mile which is quite easy to beat. Then he reduces diameters to something much smaller than all the expensive mega projects, into the range of something where technology is well established and costs are already 1/10th of his quoted $1 bil…

> But then we should ask why don't we do that anyway? Sure. Why didn't we have electric cars before tesla? Why didn't Boeing or Lockheed Martin make reusable rockets? Alan Kay said something[1] recently that has been bouncing around my head for the past few days. He said that many people think darwinian processes (like the economy) optimize. "One my degrees is in molecular biology, and I can tell you, any biologist w…

I think both the 'people' Kay refers to and Kay himself are right. It just depends on the scale you're looking at.

Darwinian processes are near-perfectly optimized ... for an extremely local maximum. Once there, they fail to make jumps to much better nearby maxima.

If you look at a somewhat larger scale, where there are better maxima available, then the correct conclusion is that they are absolutely not optimized.

Re: The Boring Company FAQ

#204

Post by politician »

gosheroo wrote: post #30

If speed is key, what about developing nuclear-powered TBMs?

Put a rocket on it; converting the thrust to electrical energy to drive the system.

https://www.youtube.com/watch?v=9-_xfTUs3R0

(These things are pretty inefficient, but it'd be a way to wrap SpaceX into this new company along with Tesla.)

Re: The Boring Company FAQ

#205

Post by agjacobson »

This is a little crazy. Because of too much surface traffic, let's bore tunnels and develop sleds. The problem is: inefficient use of the existing infrastructure, 1 person per car, and the like. This wii be improved by the sharing of vehicles, and the driving of vehicles in formations by filing flight paths, using driverless technology. Cars are a highly unattractive investment anyway, a $50,000 car sits unused 23 hours a day. I am also skeptical that right of way, permits, and local governments could ever be satisfied by this scheme. And one pleasure of driving is looking out the window. You want to go in tunnels? By yourself? Oh you will work?

Nahh.

Re: The Boring Company FAQ

#206

Post by Cthulhu_ »

erentz wrote: post #74
Animats wrote: post #61

So, the key ideas are: - Smaller diameter tunnels. 14' is suggested. This is slightly larger than the deep London Tube lines. - Electrically powered TBMs. Those exist. However, often the business end of the machine is hydraulically powered. Musk is probably thinking of going all electric, at least for the cutter head. After all, he has lots of experience with high-torque electric motors. - Do cutting and tunnel ring…

Yeah this is all very odd and everyone is lapping it up. He claims to want to reduce tunneling costs by a factor of 10, but starts by quoting a very high benchmark of $1 billion per mile which is quite easy to beat. Then he reduces diameters to something much smaller than all the expensive mega projects, into the range of something where technology is well established and costs are already 1/10th of his quoted $1 bil…

With the capacity in mind, this project will end up having much lower throughput than a regular road, even when taking congestion in mind - unless they build dozens of parallel tubes, in which case the costs will become very, very large. I also don't see it becoming a long-distance alternative, again because tunneling is a slow and long process.

It would be interesting I guess if they combined it with the Hyperloop concept, board the tube system in the city, transition to a (cheaper?) above-ground vacuum tunnel system at a transit station.

But it's all very science-fiction and, if anything, it's not going to be cheap. Like, at all.

At least it's a commercial project, not something a government has to pay for.

Re: The Boring Company FAQ

#207

Post by elihu »

arcticbull wrote: post #159
elihu wrote: post #110

Earlier quoted context omitted.

Because the decision whether or not to invest in public transport is a political one. A private company can't force society to allocate more tax money to public transport infrastructure. It can, however, provide more attractive infrastructure options, which seems to be what the Boring company is trying to do.

It could just build transit though couldn't it? Instead of sleds? Private companies operate passenger and freight rail networks, especially in the UK to my understanding.

I believe they're usually heavily subsidized. Possibly, if a private company could reduce costs enough they could operate a transit system without subsidies and make money doing it, but I think ordinarily a private company running public transit is heavily reliant on government support. (Bus networks might be an exception, since they can use the roads that already exist and there isn't a huge up-front cost.)

It sounds like the Boring company is mostly interested in providing the capability to make small tunnels cheaply. The car sled thing is just one possible way to use the tunnels, but if some city wants to do something different with them that's up to them.

Re: The Boring Company FAQ

#208

Post by Cthulhu_ »

picosat wrote: post #184
djsumdog wrote: post #151

Earlier quoted context omitted.

But even with the stations, escalators and everything else, you're talking about orders of magnitude between trains and cars. London during peak hour has trains arriving less than 1 min 30 sec apart. They move an absolutely insane amount of people. Singapore's trains are entirely automated and arrive at Everything about Musk's idea seems absolutely terrible. If America had better trains and subways, it could move mas…

The American obsession with "alone time" is exactly why Musk's idea is the only effective way to relieve the traffic problem. Americans are adverse to change, and the result of this is a solution needs to leverage our existing infrastructure. Putting the cars on sleds allows people to keep the luxury and flexibility of personal cars without requiring a lifestyle shift. Furthermore, a solution that leverages personal…

> Americans are adverse to change

I don't get it, where does that come from anyway? I mean America's mostly a country of immigrants; most inhabitants' forefathers, only a couple generations ago, abandoned everything they know to build up a new life. If that's not change, then IDK what is.

I think that at one point it's not about what they want - having the option even to drive anywhere is a luxury a lot of people don't have - it's what's practical. Driving in New York isn't practical, so people take the tube - regular services, high capacity, etc. There's no way a tunnel system with individual cars, which will have a much lower capacity than a regular road, will be able to compete, neither on cost nor capacity.

Of course, if you're rich then it doesn't matter. I'm sure it'll work in SF, where there should be plenty of people that can afford it.

Re: The Boring Company FAQ

#209

Post by hwillis »

espadrine wrote: post #199
Animats wrote: post #61

So, the key ideas are: - Smaller diameter tunnels. 14' is suggested. This is slightly larger than the deep London Tube lines. - Electrically powered TBMs. Those exist. However, often the business end of the machine is hydraulically powered. Musk is probably thinking of going all electric, at least for the cutter head. After all, he has lots of experience with high-torque electric motors. - Do cutting and tunnel ring…

> Issues glossed over: Soil variability. … The back end. Good points. And beyond the technical aspects, there's a lot that the FAQ doesn't say about the service: - How do you tell your sled where to go? Does it always go to the same place? If so, do you merge lanes? If you merge lanes, wouldn't there be jams there? If instead you build many parallel tunnels, don't you remove the gains you had from building smaller tu…

TBMs can turn, albeit slowly. Bigger tunnels are not necessarily more efficient than parallel tunnels. Consider changing a 1 lane to a 2 lane tunnel. You can dig two adjacent tunnels, or you can use a TBM that is twice as wide, and therefore has to remove 4x as much material. Even if you can only build 2 or 3 TBMs per bigger TBM, it's a win.

The tunnels are still pretty big, and the sleds could be 10' wide and 10' vertical if the tunnel ID is 14'. That's pretty comparable to a subway or bus, and the increased distance between the sleds is made up for by the increased speed.

Re: The Boring Company FAQ

#210

Post by aMayn »

Tunnel construction/operation is silent to anyone on the surface.

I am pretty sure the neighbours of the Copenhagen metro construction sites would wholeheartedly disagree.

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