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Does it make sense to make a large capital bet on mass transit at this time? Yesterday, Telsa released a video of their new car self-driving, including dropping

Does it make sense to make a large capital bet on mass transit at this time? Yesterday, Telsa released a video of their new car self-driving, including dropping a passenger off and getting into a parking lot. It strikes me that a personal rapid transit system - think something like Uber, operating on lanes dedicated to self-driving cars - could provide much of the functionality of this, and be ready a lot sooner.

jseliger 10y ago
Short answer: Yes. I don't have time to dig up the studies or articles at the moment, but even optimistic-case self-driving car systems aren't going to more than double or triple existing road capacity. Good rail systems already, today, have about 5 – 10x the capacity of road systems. Self-driving cars and medium- to long-distance urban transit system are actually likely to be complements, not substitutes, especially if/when cities continue to get denser.
- alooPotato 10y ago
  What about shared self driving cars + dedicated express bus lanes? The idea being we tax cars for usage of the road and the buses become effectively free (and faster) while self driving shared ubers are $2/ride. Making roads better and taxing them right (so we can do dynamic pricing) seems so much better than huge chunky capital costs of digging tunnels and installing subway infrastructure. We already have roads, people get to go door to door, and deploying a usage based tax model on roads is just software. Seems so much better than decade long projects.
  - tajen 10y ago
    There's a lot of added value for the community in mass transport. It costs less per fare than car systems you can think about (even ridesharing & co), consume/pollute less, but more importantl it allows lower-class and middle-class citizen to move around the city. All the cleaning personel, food, assistance personel can afford coming to the city to provide for high-value-added workers. All high-value-added can afford to live farther away along the lines, in better appartments than the constricted downtown space. And the new density created by gathering more people in the same place during the day allow the collaboration of more people.
    - alooPotato 10y ago
      agreed. but buses instead of subways no?
      - ufo 10y ago
        When it comes to transport capacity its usually Subway >> Light Rail ~ Bus Rapid Transit >> Regular Bus >> Cars
        alooPotato 10y ago
        I'm imagining buses that go down major arteries like Geary. They'd come often and there would be a lot of them and they'd have dedicated lanes. Seems so much more flexible than fixed infrastructure.
        ufo 10y ago
        Public transit doesn't need to be flexible though. Individuals might change their routines every day but when you average the traffic for the whole city the throughtput of the major arteries is very predictable. The biggest priority in these situations is making the transport be cheap and efficient and make it scale to demand. And just because a mode of transportation is on wheels doesn't mean it flexible. If you look at a Bus Repid Transit system[1] you would notice that the buses are specialized for driving in separate lanes that go in a straight line and the bus stops are custom built (and are less frequent than a regular bus). [1] https://en.wikipedia.org/wiki/Bus_rapid_transit https://en.wikipedia.org/wiki/Bus_rapid_transit
    - eru 10y ago
      > All high-value-added can afford to live farther away along the lines, in better appartments than the constricted downtown space. Just build up. There's plenty of room in downtowns. The elevator can be the most important form of `public transport'.
      - closeparen 10y ago
- sliverstorm 10y ago
  For the compliment story- One of the challenges with things like rail is getting to and from the station, and parking. If you could step out your door, ride to the train, get dropped off, get on the train, get off, and ride to your office- rail could become dramatically more compelling for people who are not very close to the stations. In short self-driving cars could improve rail's "last-mile" challenge
- closeparen 10y ago
  >Good rail systems already, today, have about 5 – 10x the capacity of road systems Do they have that capacity in seats or in hands on the overhead rails with backpacks held in hands and zero personal space? If the latter, that's a fairly disingenuous comparison.
  - eru 10y ago
    Why? Still gets you from A to B.
    - closeparen 10y ago
      Banning air conditioners in the South would be great for energy efficiency. It's just comfort, not survival. Forcing people out of cars (or previously available train seats) onto standing room only trains because "you still get from A to B" would be roughly the same. Everything is "more efficient" if people simply accept worse outcomes. That's not an accomplishment. Contrast with actual improvements over status quo like more effiently packed passenger cars, self driving cars, rail service with enough seats, etc. Upward change is good. Lateral change is fine. Reaching into people's lives and making them worse because "you didn't really need that, and my values are more important than yours" is disturbingly fashionable in these threads.
      - eru 10y ago
        I agree, but the context of my comment was jseliger comment further up about capacity alone. No need to force people out of cars. But often the limiting factor for road transport happens to be congestion: when people are in effect running an auction with their time, and persons most willing to set in traffic are the highest bidder and `win the road'; then it is economically more efficient to make people pay with money instead of time and introduce a congestion charge or an Certificate of Entitlement system like in Singapore. The road still gets rationed by an auction, but instead of bidding by wasting your time, you bid with actual money that can be re-used for other things. (And time is, of course, money.) I hope you forgive me what seems like a digression: what looks like `forcing people out of their cars' might actually just be replacing wasteful time-bidding with money-bidding.
deleted 10y ago
[deleted]
chrismealy 10y ago
https://img.washingtonpost.com/blogs/wonkblog/files/2015/08/7hAJ4qG1.gif https://img.washingtonpost.com/blogs/wonkblog/files/2015/08/...
SilasX 10y ago
Unless that's a self-driving clown car, it's not a substitute -- it can't have the person density or be protected from having to yield to other traffic like a subway can.
raldi 10y ago
Quoth the SFMTA's Liz Brisson: There’s no way that autonomous vehicles running on surface streets gets you the level of capacity that grade-separated high-capacity transit gets you. I don’t think I’ve heard anyone argue that it will. E.g. a 10-car BART train with 119 passengers per traincar running at 24 trains/hour today and 28/hour in the future with ATCS upgrades.
marcoperaza 10y ago
Everyone who is discounting this criticism is assuming that it's either self-driving cars occupied by a single person each, or mass fixed-rail transit. That's a bogus assumption. Self-driving uberpool-like services, self-driving buses, etc. will also play a role. Building fixed-line transit at this point is a massive waste of money. But construction is where the action is in local corruption, so they'll keep doing it.
pdx6 10y ago
You seem to be getting down-voted, but autonomous public transportation is a good thought exercise, and yes it already exists on (small) rubber tire fleets. There are some unresolved problems here, such as where do all the SDCs go when empty? Are they leased? Do we have parking garages with empty cars going in and out of them all day? How do we charge for that? How does this impact green house gas emissions? Even dedicated SDC lanes would have a maximum hourly capacity. SDCs are a good last mile solution, particularly in mid density areas and for the disabled. Conventional trains make more sense to delivering large amounts of people to or from a city center as well general regional transportation.
- capkutay 10y ago
  Hey pdx, I'd love to help out as a SF transit advocate in any way I can. Feel free to shoot me an email.
bbcbasic 10y ago
Yes another automation factor is automated deliveries that can happen during the night rather than during office hours. And remote working + VR - say no more!

jseliger 10y ago

Short answer: Yes. I don't have time to dig up the studies or articles at the moment, but even optimistic-case self-driving car systems aren't going to more than double or triple existing road capacity. Good rail systems already, today, have about 5 – 10x the capacity of road systems. Self-driving cars and medium- to long-distance urban transit system are actually likely to be complements, not substitutes, especially if/when cities continue to get denser.

alooPotato 10y ago
What about shared self driving cars + dedicated express bus lanes? The idea being we tax cars for usage of the road and the buses become effectively free (and faster) while self driving shared ubers are $2/ride. Making roads better and taxing them right (so we can do dynamic pricing) seems so much better than huge chunky capital costs of digging tunnels and installing subway infrastructure. We already have roads, people get to go door to door, and deploying a usage based tax model on roads is just software. Seems so much better than decade long projects.
- tajen 10y ago
  There's a lot of added value for the community in mass transport. It costs less per fare than car systems you can think about (even ridesharing & co), consume/pollute less, but more importantl it allows lower-class and middle-class citizen to move around the city. All the cleaning personel, food, assistance personel can afford coming to the city to provide for high-value-added workers. All high-value-added can afford to live farther away along the lines, in better appartments than the constricted downtown space. And the new density created by gathering more people in the same place during the day allow the collaboration of more people.
  - alooPotato 10y ago
    agreed. but buses instead of subways no?
    - ufo 10y ago
      When it comes to transport capacity its usually Subway >> Light Rail ~ Bus Rapid Transit >> Regular Bus >> Cars
      - alooPotato 10y ago
        I'm imagining buses that go down major arteries like Geary. They'd come often and there would be a lot of them and they'd have dedicated lanes. Seems so much more flexible than fixed infrastructure.
        ufo 10y ago
        Public transit doesn't need to be flexible though. Individuals might change their routines every day but when you average the traffic for the whole city the throughtput of the major arteries is very predictable. The biggest priority in these situations is making the transport be cheap and efficient and make it scale to demand. And just because a mode of transportation is on wheels doesn't mean it flexible. If you look at a Bus Repid Transit system[1] you would notice that the buses are specialized for driving in separate lanes that go in a straight line and the bus stops are custom built (and are less frequent than a regular bus). [1] https://en.wikipedia.org/wiki/Bus_rapid_transit https://en.wikipedia.org/wiki/Bus_rapid_transit
  - eru 10y ago
    > All high-value-added can afford to live farther away along the lines, in better appartments than the constricted downtown space. Just build up. There's plenty of room in downtowns. The elevator can be the most important form of `public transport'.
    - closeparen 10y ago
sliverstorm 10y ago
For the compliment story- One of the challenges with things like rail is getting to and from the station, and parking. If you could step out your door, ride to the train, get dropped off, get on the train, get off, and ride to your office- rail could become dramatically more compelling for people who are not very close to the stations. In short self-driving cars could improve rail's "last-mile" challenge
closeparen 10y ago
>Good rail systems already, today, have about 5 – 10x the capacity of road systems Do they have that capacity in seats or in hands on the overhead rails with backpacks held in hands and zero personal space? If the latter, that's a fairly disingenuous comparison.
- eru 10y ago
  Why? Still gets you from A to B.
  - closeparen 10y ago
    Banning air conditioners in the South would be great for energy efficiency. It's just comfort, not survival. Forcing people out of cars (or previously available train seats) onto standing room only trains because "you still get from A to B" would be roughly the same. Everything is "more efficient" if people simply accept worse outcomes. That's not an accomplishment. Contrast with actual improvements over status quo like more effiently packed passenger cars, self driving cars, rail service with enough seats, etc. Upward change is good. Lateral change is fine. Reaching into people's lives and making them worse because "you didn't really need that, and my values are more important than yours" is disturbingly fashionable in these threads.
    - eru 10y ago
      I agree, but the context of my comment was jseliger comment further up about capacity alone. No need to force people out of cars. But often the limiting factor for road transport happens to be congestion: when people are in effect running an auction with their time, and persons most willing to set in traffic are the highest bidder and `win the road'; then it is economically more efficient to make people pay with money instead of time and introduce a congestion charge or an Certificate of Entitlement system like in Singapore. The road still gets rationed by an auction, but instead of bidding by wasting your time, you bid with actual money that can be re-used for other things. (And time is, of course, money.) I hope you forgive me what seems like a digression: what looks like `forcing people out of their cars' might actually just be replacing wasteful time-bidding with money-bidding.

deleted 10y ago

[deleted]

chrismealy 10y ago

https://img.washingtonpost.com/blogs/wonkblog/files/2015/08/7hAJ4qG1.gif https://img.washingtonpost.com/blogs/wonkblog/files/2015/08/...

SilasX 10y ago

Unless that's a self-driving clown car, it's not a substitute -- it can't have the person density or be protected from having to yield to other traffic like a subway can.

raldi 10y ago

Quoth the SFMTA's Liz Brisson: There’s no way that autonomous vehicles running on surface streets gets you the level of capacity that grade-separated high-capacity transit gets you. I don’t think I’ve heard anyone argue that it will. E.g. a 10-car BART train with 119 passengers per traincar running at 24 trains/hour today and 28/hour in the future with ATCS upgrades.

marcoperaza 10y ago

Everyone who is discounting this criticism is assuming that it's either self-driving cars occupied by a single person each, or mass fixed-rail transit. That's a bogus assumption. Self-driving uberpool-like services, self-driving buses, etc. will also play a role. Building fixed-line transit at this point is a massive waste of money. But construction is where the action is in local corruption, so they'll keep doing it.

pdx6 10y ago

You seem to be getting down-voted, but autonomous public transportation is a good thought exercise, and yes it already exists on (small) rubber tire fleets. There are some unresolved problems here, such as where do all the SDCs go when empty? Are they leased? Do we have parking garages with empty cars going in and out of them all day? How do we charge for that? How does this impact green house gas emissions? Even dedicated SDC lanes would have a maximum hourly capacity. SDCs are a good last mile solution, particularly in mid density areas and for the disabled. Conventional trains make more sense to delivering large amounts of people to or from a city center as well general regional transportation.

capkutay 10y ago
Hey pdx, I'd love to help out as a SF transit advocate in any way I can. Feel free to shoot me an email.

bbcbasic 10y ago

Yes another automation factor is automated deliveries that can happen during the night rather than during office hours. And remote working + VR - say no more!