But what to do with all the dirt?
Perhaps they aren't fully aware of the volume disturbed soil takes up. Logistics of moving it could be a cost not necessarily considered.
371–380 of 472 posts
But what to do with all the dirt?
Perhaps they aren't fully aware of the volume disturbed soil takes up. Logistics of moving it could be a cost not necessarily considered.
I wish them the best of luck but I can't help feel the entire premise of the company is based on a pun.
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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 c…
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…
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 c…
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The car in the video looks like Model S size. About 16 feet long. Add 2 feet on each end for an even 20 feet for the sled. At 125mph one gets 660,000 feet per hour. So if you can pack the cars next to each other, the maximum is 33,000 cars per hour. So 33,000 people per hour with each person getting a space that would rent in SF for $1000/month. Pack that sled space with people at the same density as a train at rush…
>each other, the maximum is 33,000 cars per hour. Yeah, but that's 33,000 cars per hour without any of the cars stopping to exit the tunnels. The trains used in BART and other public transit systems can very easily exceed 60+mph already, but they don't because they have to stop, bringing down the average speed of the system. BART, by the way, does 28000 passengers per hour per direction in the Transbay Tube ( https:/…
Of course the sleds in an operating system would not be absolutely packed together. This was just a Fermi estimation to get some idea of the flow rate the parent comment was wondering about. Looks like max rates would vary from somewhat worse than trains to much better.
The sleds would be automated so that when one wants to exit the others would give it enough space to do so without problems. Another Fermi estimation could be done to get an idea of how long the exit tunnel would need to be for a sled to stop given a range of deceleration rates.
I think Musk is on the right track but that his biggest hurdles may be social and political in the USA. Maybe China or India will want to try it out (or the Swiss).
[1] https://www.bart.gov/sites/default/files/docs/2016Factsheet_...
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How about bus pods directly after bus pods? It'd be comparable or even higher (20 passengers/pod).
Congratulations, you just reinvented the train.
Those aren't new either, but not common for urban transportation.
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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If NYC didn't have a third dimension for transportation (subway and trains), no amount of busses and bikes would fix the soul-destroying traffic. The listed alternatives are all nice, but none of them allow you to move at 125+ mph. We should be able to get to our destination faster, not just with a bit less soul-destruction. Remote work is of course not for every or even most professions, and I don't see why it would…
> If NYC didn't have a third dimension for transportation (subway and trains), no amount of busses and bikes would fix the soul-destroying traffic. Yes they would. If you took the existing surface street network and made it 100% buses and/or ground-level trains you could accomodate current subway and road capacity with room to spare, even before you reclaimed all the space currently used for car parking. Private cars…
... and buses are even worse.
NYC works because of trains and as a proponent of train travel and public transportation (except buses) I believe they have indeed solved many problems with their diverse rail network.
Buses are a canard - they are the minimum viable public transport option that were pried out of suburban taxpayer hands and presented to poor urban (usually black) riders by planners who didn't care about public transportation at all.
This ruse has gone on so long that in 2017, well meaning (and brainwashed) proponents of public transportation see buses as one of the core components of a transport network. Wake up. This is false. You need subways and trains.
Well-functioning transit in cities that prioritize it use very few buses and they use them for weird stopgap or edge cases (or emergencies). BRT is a farce[1]. You should be demanding real, not fake, investment in transit networks. You should be demanding trains.
[1] To be fair, I have seen two very functional BRT models - both in very specific (and wealthy) environments: VelociRFTA in Aspen and Hop/Skip in Boulder. In both cases, however, a well-designed rail corridor would be even better.
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>How do you tell it where to go? the giant ipad on the dashboard of your tesla, or your phone otherwise. >If you merge lanes, wouldn't there be jams there? If instead you build many parallel tunnels [etc] because if the increased speed, one lane is the equivalent of about 2.5 highway lanes in terms of throughput per hour. Regarding safety distance, I think you can actually safely achieve smaller spacing with a roller…
Using actual numbers: Melbourne's light rail E-class trams have a carrying capacity of 64 seated: 146 standing. They can regularly mix with pedestrians. The E class is the "big" one at about 40 seconds: https://www.youtube.com/watch?v=kmBlZ4xpS5Q Melbournes older, 6 car trains have a crush capacity of ~1526. Seatwise they have ~500-600, with a standard target capacity of about 800 (above that the extra variance/numbe…
The problem is that most US cities are completely unwalkable, so you need a car once you hop out of the station, or you need an incredibly large subway system.
This is being proposed for LA initially, which is one of the most sprawled, least walkable cities in the US.
I wish we had more walkable cities here.