Comment by mcv
20 hours ago
Self-driving cars still take up space on the road. Even more than human-driven cars, because now there will also be cars transporting 0 people. It's going to make congestion worse. Public transit is the solution to congestion. Well, one of the solutions, because bikes are probably a better solution for most people: they do start in front of your home, can park anywhere, and don't cause congestion the way cars do.
We're talking about cities, of course; in rural areas, nothing beats cars.
> Self-driving cars still take up space on the road
This is a false argument. Think about this: a bus every 10 minutes is effectively 500-900 meters long! It easily "takes" as much space as 100+ cars. In other words, nothing would change from the traffic perspective if instead of 1 bus every 5 minutes, you had 100 individual cars.
The "people in the shape of a bus" argument makes sense only when you're talking about the performance in a very narrow case of transporting people in a steady, uninterrupted stream of buses. Or if you need to size your traffic bottlenecks.
Moreover, a bus route necessarily is unoptimal for at least some people on a bus. They are effectively "thicker" than other people because they take up more "effective space". But wait, there's more! Buses also necessarily move slower due to stops, so the "effective length" of a bus becomes even longer because cars will clear the road faster.
But wait, there's even more! A single bus needs about 3 drivers to be effective. So with the average daily busload of around 15 people, you have almost 20% of the bus taken by the drivers on average. This makes bus trips pretty expensive. Not quite to the level of Uber/Lyft, but surprisingly close.
And these problems are fundamental. That's why urbanists like NJB don't like to talk about that.
Nothing about this addresses NJB's argument that self-driving cars take up more space than regular cars, because there will now be cars with 0 people in them.
Ultimately the thing you want to transport is not cars, it's people. Walking fits the most people in a limited amount of space, then bikes, buses and other forms of public transport, then cars with 4 people in them, then cars with 3 people in them, then cars with 2 people in them, then cars with only 1 person in them, and finally empty cars. More cars will never reduce congestion.
But to address your point: A bus in a dedicated lane takes up more space than a bus that's stuck in car traffic, you are right about that. On the other hand, when congestion is so bad that cars simply don't move, no matter how many lanes they have, getting people out of cars into more efficient forms of transport, will also help cars. And a bus that actually goes, can do that. If you look in cities with good public transport, more people go by public transport than by car. In cities with good bicycle infrastructure, more people go by bike than by car. That means even cars are less likely to get stuck in traffic in those cities. Even if you take away a car lane.
I don't know where you got the idea that a bus needs 3 drivers.
> Nothing about this addresses NJB's argument that self-driving cars take up more space than regular cars, because there will now be cars with 0 people in them.
And? There are also buses that trundle around with nobody but the driver in it. Or unused bikes and e-scooters that litter the sidewalks.
> Ultimately the thing you want to transport is not cars, it's people.
Yeah. And let's make it efficient. Put these people into 3-level bunk beds. This way they can travel all together in just 1 bus to their assigned workplace. And you don't need to run buses until they're allowed to clock off their shift.
Efficiency!
> On the other hand, when congestion is so bad that cars simply don't move
In this case you close the downtown offices and force them to work on alternate days, like they do in India with cars. Remote work already can replace 70% of all work, and with AI this number will grow.
Apart from that, mild carpooling will decrease the number of cars by 2x. Small vans with 6 seats can _easily_ remove all congestion.
> no matter how many lanes they have, getting people out of cars into more efficient forms of transport, will also help cars.
Just one ask for urbanists. Can you just stop lying, please? Just one thing. Don't say that "transit help cars". It doesn't. There is a lot of research from _you_ (e.g. https://archive.strongtowns.org/journal/2020/1/7/does-buildi... ) that proves this. Transit does NOT decrease the travel time for cars ("traffic") it _increases_ it by increasing congestion due to increased housing density that transit forces.
You want to pack people into 3x3 jails ("microapartments")? Fine. But be honest about it.
> a bus every 10 minutes is effectively 500-900 meters long!
uhhhhhh what. What does every 10 minutes have to do with this at all
> It easily "takes" as much space as 100+ cars.
are you ok??? have you seen a bus before??
> A single bus needs about 3 drivers to be effective
I have never ever seen a bus with 3 drivers in it. If you're talking about 3 drivers over the course of 24h, those drivers are not in the bus at the same time, and therefore don't make up 20% of the passengers on the bus. If you're saying the average bus route serves 15 people per day, you are certainly mistaken.
> If you're saying the average bus route serves 15 people per day, you are certainly mistaken.
Definitely mistaken for London - currently (according to DFT's numbers) about 18 people per bus average (not per day, though.)
> uhhhhhh what. What does every 10 minutes have to do with this at all
See the word "effective". Think about the road space that a bus requires but doesn't use if it is just once per 10 minutes.
> I have never ever seen a bus with 3 drivers in it. If you're talking about 3 drivers over the course of 24h, those drivers are not in the bus at the same time, and therefore don't make up 20% of the passengers on the bus.
Yes, I'm talking about the drivers that are needed for a reasonable 16-hour bus service. And the typical ratio is actually a bit more than 3 drivers per 1 bus.
> If you're saying the average bus route serves 15 people per day, you are certainly mistaken.
No. I'm saying that on _average_ there are 15 people in a bus. More during the rush hour, fewer during the off-hours.
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> We're talking about cities, of course; in rural areas, nothing beats cars.
Where I grew up in NW Scotland, it's a five hour round trip to go to the supermarket. You pretty much need a car for that.
Where I live right now it's a five minute walk to the supermarket, but I still need a car because the things I work on are a long way from where I live, often up steep muddy mountain tracks.
When I lived in the middle of Glasgow people used to come up and have a go at me about driving a massive V8 4x4 in the middle of a city. What am I supposed to do with it? Bike to the suburbs and then go and drive up a mountain?
"But why not get a job where you don't need to drive hundreds of miles in a massive 4x4?"
Because then the things on the tops of mountains don't get fixed when they break, and the radios don't work properly, and then people like you die in a fire.
Sometimes it's hard for people to grasp that just because their not-really-a-job tapping numbers into an Excel spreadsheet all day can be done from home or from an easily walkable city centre location, it doesn't mean that everyone's job looks like that.
I do wish I could usefully use a cargo bike. Those things are awesome.
What people really misunderstand in these discussions is that no one is talking about completely killing off driving as an option, and no one says that public transportation works in literally 100% of circumstances.
We just want there to be viable public transportation options for situations where it makes sense. This even makes it easier for the people who do have to drive, like you, as there will be less congestion because a single bus can replace literally dozens of cars, combine that with a single tram and a single metro car and you're replacing literally hundreds of cars that would otherwise be on the roads instead.
Exactly. It would be awesome if we had viable public transport options in rural areas too, although necessarily they would not be as frequent of flexible as in cities. There wouldn't be the requirement for them so much, because of the lower population density and the different patterns of vehicle use.
But growing up in a rural area where there are two buses a day none of which are useful for anything other than high school pupils (although they're not school buses) it does tend to limit everyone's options.
> What people really misunderstand in these discussions is that no one is talking about completely killing off driving as an option
I find this statement utterly hypocritical. Sure, we're not killing off driving. We are just choking off the roads with bike lanes, forcing extra-high density ("just build more"), removing parking, forcing the drivers to pay for transit that they don't use, and just to pay in general.
But no, we're not preventing driving. Not at all.
Urbanists want to stop people from using cars as much as they can force that.
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