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The Boring Company FAQ

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Re: The Boring Company FAQ

#431

> Since concrete production accounts for 4.5% of the world’s greenhouse gas emissions, there is no way this is even close to being correct. For a point of comparison, "Airlines account for about 2 percent of global emissions". just how much concrete does this guy think is being produced. come on. He probably misreported a figure that said concrete production accounts for 4.5% of all construction-related greenhouse ga…

Concrete production actually does have crazy CO2 emissions. Wikipedia says it's up to 5% globally:

https://en.wikipedia.org/wiki/Environmental_impact_of_concre...

Re: The Boring Company FAQ

#432
post #186

Earlier quoted context omitted.

One problem is that trains only move an insane amount of people that are all going the same way. Another problem is that all those people have to walk to and from the end station. A "packet switched" system of sending individual cars at high speed solves both those problems, and going just by my gut feel, should have a quite high throughput too.

>One problem is that trains only move an insane amount of people that are all going the same way. Another problem is that all those people have to walk to and from the end station. A "packet switched" system of sending individual cars at high speed solves both those problems, and going just by my gut feel, should have a quite high throughput too. People are walking from the station to these giant office towers in cen…

Sure, this system works great in the center of one of the biggest cities in the world. That's not in dispute.

Where mass transit struggles is in getting people from one arbitrary spot to another at an arbitrary time.

Re: The Boring Company FAQ

#433
post #176

Earlier quoted context omitted.

Cities like LA will become denser over time. It might seem counterintuitive but increasing density alleviate traffic (people walk). You can't clean a hotel or flip a burger remote. Public transit has failed to solve the problem despite a 100-year head start. Cycling... in LA... I don't think the Boring Company is trying to solve the gridlock. They will, however, provide an option for those who can afford to pop down…

> Public transit has failed to solve the problem despite a 100-year head start. Public transit SOLVED the problem 100 years ago in the US. And then it was sabotaged by the big automakers.

>Public transit SOLVED the problem 100 years ago in the US. And then it was sabotaged by the big automakers.

I think American Individualism sabotaged Public Transit when it realized it could avoid the public by using automobiles.

Re: The Boring Company FAQ

#434
post #342
post #234

Earlier quoted context omitted.

> Musk is not going to push forward a venture like this without loads of research from a team of really smart people. It's not like it's just the one Elon with a fantasy about tunnels. It'd start with a bunch of talented people brainstorming and then, early in the process, they'd surely be speaking with really knowledgeable people who know the industry and pitfalls. Actually, the story is that Musk made it up on a wh…

Same as the Hyperloop story. Just that the Hyperloop story wasn't true, it was really conceived by Et3. And in general - entrepreneur "origin" stories are often bullshit - useful to get go PR, that's it.

>the Hyperloop story wasn't true, it was really conceived by Et3

You might want to look at them closer. Hyperloop and ET3 are very different from a technical perspective, even though they're superficially similar.

ET3 tubes need 1/1,000,000th of an atmosphere to mitigate the sonic boom, and that makes the pumping requirements exceedingly hard (requiring multi-stage pumping with turbo- and cryo-pumps). That also means ET3 has a higher top speed, assuming you can secure the right-of-way to satisfy the minimum curve radius.

Hyperloop tubes use 1/1,000th of an atmosphere, chosen because it's the lowest pressure achievable with purely mechanical pumping. They then route air around the pod, allowing them to approach the speed of sound despite the fact that air has to speed up as it squeezes around the pod (aka the https://en.wikipedia.org/wiki/Kantrowitz_Limit).

So ET3's pumps see basically the same differential pressure, but 1,000x more volume needs to be pumped per m^3 of air that leaks in. This means the Hyperloop requires less pumping power, fewer pump units, uses only cheap mechanical pumps, and can tolerate more air leakage than ET3. This is a big win, since the tube is the expensive part.

Re: The Boring Company FAQ

#436
post #74
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…

I kinda wonder if the tunnel-borers are meant for Mars.

Re: The Boring Company FAQ

#437

Earlier quoted context omitted.

OTOH JR Central is in the process of building a tunnel from Tokyo to Nagoya: https://en.wikipedia.org/wiki/Chūō_Shinkansen

Yes, for a MagLev train that achieves the fantasy of hyperloop (but is actually happening now). From my perspective, hyperloop and TBC are each 100% upside down in terms of their approach. America can only dream of 505km/hr interstate ground transport. I'm writing this from aboard the Nozomi express Shinkansen at around 300km/hr, by the way. Just left 名古屋駅.

Hah, amused to be able to read kanji after so many years (nagoya-eki :P)

I have ridden on the Nozomi and it's a fantastically smooth ride. There are indicators of the current speed on the wagon passage doors and it is incredible when it achieves 270+ km/h and everything is passing by so quickly, and yet you can drink your beverage from a cup just fine, just like in an airplane :)

Re: The Boring Company FAQ

#438

Earlier quoted context omitted.

> 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…

I think LA is an even better example of where it will work. There are no trains, and the bus system is very poor. The tunnels obviously don't make sense in places that have well established train systems, but a lot of places don't have that. Often in America, the only 'practical' way to get around is using a personal vehicle.

Your information is out of date - over the last 20 or so years, LA has built itself a train network:

https://en.wikipedia.org/wiki/Metro_Rail_(Los_Angeles_County...

Re: The Boring Company FAQ

#439
post #74
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…

It's already been mentioned that putting cars in the tunnels increases the usefulness of the tunnels quickly without requiring a large network of tunnels right off the bat. I think it's always possible to convert the tunnels to trains at a later date with a much lower cost than the initial investment. I think having the tunnels be designed for cars makes a lot of sense for Elon in particular because he can design the tunnels as an ideal environment for the first generation of self driving cars. This would give him a good start getting self driving cars on the road.

Re: The Boring Company FAQ

#440
post #298

Earlier quoted context omitted.

The throughput will be tiny because cars take up so much space. http://humantransit.org/2012/09/the-photo-that-explains-almo...

And cars more inefficiently in groups. When at lights, the first car pulls away, then the second, etc etc... There is a delay between each car which after 20 cars really adds up.

This doesn't apply to the centrally controlled car delivery system Musk is planning.
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