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by dymk 1137 days ago
Good public mass transit is absolutely superior. Waymo cars don't solve traffic, it only partly solves parking and paying a human.

Having (on average) a single person take up 40 square feet of space on the road for travel is horribly inefficient. You do a few orders of magnitude better with a full train car or bus.

3 comments

Not only don’t autonomous cars solve traffic, they will actively make it worse. The marginal cost of operating a car drops dramatically when you remove the human drivers from them (who also suffer from pesky conditions like boredom and drowsiness), and so we can expect these vehicles to drive signficantly more frequently than their human-operated cousins.

Think about uses like DoorDash. Instead of (in a city) walking to nearby restaurants, we now replace a larger share of those dinners with ones where cars are driving back and forth across the city to pick up the food and deliver it. This will only become more common when the cost drops by not having to pay a human being, and so we can expect a much greater volume of traffic from this one example use.

Other currently-marginal use cases will see equivalent growth due to the similar economics.

Most buses off rush hour are sparsely populated. Look up actual energy efficiency of American mass transit systems per rider mile. https://www.templetons.com/brad/transit-myth.html

Re traffic: with robot-driven cars, congestion pricing would be technically easy. This is an example of not considering possibilities created by the new tech.

You are comparing with the least efficient form of transit, and looking at cities that are not really designed for transit anyway. So yes, bad transit in cities not designed for it isn't that efficient. Note, on top of this, that you are purely looking at energy efficiency, when the key problem of individual robotaxis is space efficiency.

Realistically, what breaks efficiencies in the US is city design: Places of work mostly detached from activities and housing, pretty much guaranteeing inefficiency. The robotaxis don't make a difference here: The max number of people looking to travel at once doesn't change, and neither does their destination. This makes the number of vehicles actually on the road not change very much at all: The best you can do is hope for people being comfortable (and not inconvenienced) by carpooling with strangers, not unlike what lyft and uber offer already. In the middle of the day, there's no new demand for robotaxis: They'd be parked somewhere, and every mile they move is a car/mile of congestion they create. So you either park the cars where the jobs are, getting, in practice, the same results as private vehicles, or you park them somewhere else, increasing total congestion. It's not just robotaxis that would park: See what happens in all the train commuter lines in American cities, where most trains just get parked in a yard.

The miracle of cities with top transit (See, for instance, Madrid), is that a relatively high percentage of the network is about equally busy in both directions. Trains might stop in rush hour, but route 6 will be useful in either direction most of the time, with little waste compared to US cities. This is the real weakness of the argument of just adding more transit: What we need to make it work is basically urban rebuilds. IMO still a good idea, bit it's a far slower, and more expensive problem than it might appear.

Most roads off rush hour are sparsely populated; seems inefficient, let's pedestrianize them.
With autonomous vehicles we could! You could safely bike coast to coast on the shoulder of any highway. The possibilities are truly spectacular.
Autonomous vehicles will not make cycling or walking next to much faster multi-ton vehicles more pleasant, even if those vehicles are less likely to kill you. I mean, have you walked along even a 35mph road with significant traffic? It's extremely unpleasant due to the noise and air pollution.

In fact, today the area around elevated freeways is often much cheaper than the surrounding area for several blocks.

Thank you
Good for your rich tech salary utopia to have congestion pricing and pay for it to get ahead of the rest.

People with lower income benefit from having a decent bus system that doesn’t require them to pay $10K a year on a car.

They were wrong and their argument was bad, but it remains a fact that America has dismal public transit compared to other developed nations (which is why their argument was bad).
London is looking at apeing some Uber-like technology but for paying to drive your own car.
Congestion pricing is congestion pricing because traffic is bad. Waymo doesn’t solve traffic.
Robo cars are more expensive during peak usage, so they can form habits where public transit is both encouraged because I took a robocalled to work and the bus home because then it was rush hour, or Vice versa. Or I took the bus to work and left late at night after the buses stopped running via a robo taxi…etc. All this occurs with Uber already, I don’t bother renting a car because even though it sucks to take the bus from the airport, I can Uber that and use more efficient transit when available, since I have something that fills in the gaps. Robo cars just make that link more efficient (lower cost eventually as humans become more and more expensive).

They make not taking your car with you a bit more feasible, and that’s a start at least.

it solves static traffic, which in many cities will solve traffic
How does it solve static traffic? Do you mean parking? Because a Waymo car takes up just as much space on the road as a human driven one.
Traffic isn't a function of road space. The true throughput of roads is immense when utilized by better drivers (one extreme example: https://www.youtube.com/watch?v=4pbAI40dK0A). A lot of traffic is caused by bad human drivers: accidents (and associated rubbernecking), shockwaves, running red lights, double parking, circling around looking for parking. Additionally entire additional lanes of traffic (for cars or personal mobility vehicles) will be available when streetside parking isn't necessary. Personally I look forward to the possibilities of turning all that unecessary parking space into something useful ("we’re the Saudi Arabia of developable land in cities").
> Look up actual energy efficiency of American mass transit systems per rider mile.

Could you pick a worse example?

Good public mass transit presumably involves cops kicking out the smelly homeless people, right? I don't think that would fly in most places these days though, it isn't humane. Yet it's the only way to make public transit tolerable.
A better idea might be to provide the homeless with a better standard of living, therefore making them nicer to be around on public transport
Some of them aren’t merely lacking access to resources. Mental illness is part of the picture too. Trains and busses are warm comfortable places for such, as well as the criminal element. People think of bus and subway stations as dirty and often dangerous places, not just in the USA.
I don't know if they're un-homed or not, but I've encountered a lot of people smoking, shouting, or making a mess with food in rail cars, making them unusable for everyone else.
You can't make them wipe.