Just like cars that we drive, self driving cars enable sprawl. Sprawl will never be environmentally sustainable. We need cities that you move through by foot, bike, and public transit.
I will say that self-driving cars help a bit in getting people to bike, though. The biggest barrier to biking in San Francisco is people's fear of getting killed by cars (the SF Bike Coalition has done surveys on this). Self-driving cars should pose less of a risk to cyclists - they don't run red lights or speed, etc.
Another potential benefit would be reducing the need for parking. The biggest obstacle to physically separated bike lanes is the space they take up - typically that requires removing parking. If self-driving taxis are super cheap, that should lead to less car ownership, and possibly less demand for parking.
That's all very speculative though.
A great commuter rail system is what allows people who work in the world's premiere cities to live in strip-mall exurbs and take the train to work.
I live in Washington, DC. Metro is what allows huge numbers of people to live in sprawling suburbs instead of in the city. Yes, some drive, but traffic is rough and would be unbearable without Metro. Fewer people would be able to live outside the dense city center.
A massive proportion of the DC area population lives in the burbs, drives to a cheap/nearby parking garage at a transit center, and then takes mass transit into the city to work.
This lifestyle would be impossible without mass transit.
What makes you think that density/economic output are the main factors in how much public transit actually gets built?
EDIT: I actually love public transit, but I just don't see any evidence that it does anything but encourage sprawl just like cars do. Also, public mass transit's environmental advantage over cars will vanish with electrification. What public transit does do extremely well is get people from A to B with high throughput. That by itself is highly valuable in any major city.
It will make the politics of building mid-rise housing without extensive, expensive underground parking space a lot more politically palatable in American cities. The same is true of replacing parking with pedestrian and bike infrastructure. And that says nothing about the safety benefits that will make cycling and walking a lot more pleasant and accessible in a lot of the US. (There are no technical barriers to building mid-rise urban housing without parking and replacing parking with high-quality pedestrian and bike infrastructure in the US today, but the politics are very difficult as drivers treat free/cheap access to city-owned street space as a right)
Plus, urbanites paying the marginal per-mile cost of a robotaxi trip, as opposed to buying a car as a huge sunk cost and then trying to get the maximum use from it, means that people will consider the car-versus-transit-versus-bike economics a lot more often, rather than buying a car and becoming someone who drives everywhere.
In cities and dense inner suburbs, parking is a limiting factor to higher density; typically every parking spot is taken, and then some.
Also, automatic driving could greatly improve the cost and convenience of public (or private fleet) transit.
And yet https://www.nytimes.com/2017/09/01/opinion/cities-suburbs-ho...
"Despite the hype around “micro-apartments” and other innovations intended to cram more people into less room, many Americans still want space. They want to live in detached suburban homes, or in an apartment with enough square footage and access to outdoor space that it feels like one. Two-thirds of people born since 1997, including those who live in cities, want to live in single-family suburban homes, according to a 2015 survey, but the costs make this aspiration prohibitively expensive in most urban centers."
We actually did decent low density non-sprawl until after WWII. Find it at the center of any city that existing before that (and wasn't bulldozed).
Assuming clean, renewable energy powers all electric mobility, why not? I do not want to live in a city/urban area, and I will pay more not to.
EDIT: @InitialLastName
Sorry, HN throttling kicked in, can't reply to your reply so I'm putting this here.
If I have a well for water, septic for sewage, solar on my roof, and a gravel road to town, what's the problem? I understand its super expensive for cities to deliver utilities and services across sprawl, but if I'm not asking for those services and utilities to be provided, it should be a non-issue.
If anything, sprawl will make service and utility delivery more efficient, as we'll have no other choice for those who choose that lifestyle.
Have a look at the graph of the cost of delivering utilities. This isn't about environmental sustainability as much as long-term economic sustainability.
When towns sprawl, utilities with costs that scale with distance cost more per person.
When factored in with total cost of living are these cities cheaper or more expensive? I can think of plenty of dense efficient cities that are more expensive than cities with sprawl.
That StrongTowns blog graph is intentionally misleading. It's not a cost of delivering utilities, it's a cost of utilities based on tax revenue a given parcel generates. It's an attempt to make cities "for profit".
Obviously, anywhere significant amounts of people live is going to come up "red", because we don't tax people the same rate we tax corporate offices, and because people use more resources there (most people live / cook / shower / sleep / etc at home, not in their cubicle).
That doesn't make it less worth that cost though (those downtown regions are only able to be "green" because there's lots of red around them). And it doesn't really have to do with sprawl. (The cost does rise with distance, but in mostly trivial ways. And those costs spiral backward again too -- 5,000 feet of new powerline in suburbia is far cheaper than 500 feet of new powerline in Manhattan, for instance).
> This isn't about environmental sustainability as much as long-term economic sustainability.
If that's the argument, then cities are almost entirely ruled out already. Cities aren't even economically sustainable for their current residents today, sprawl is the only thing preventing cities current economic issues from becoming even worse.
Sprawl is the only reason the majority of regular folks have any housing to sleep in at all.
* traffic problems will be significantly reduced * you won't need traffic lights like they exist today * the vehicles can be reduced in size (double occupancy perhaps); a family can just order a couple cars and have communication between them * streets can be reduced to fewer lanes; possibly one-way because the vehicles can navigate the best route in any case
A self-driving car increases the radius of effect of things like mass transit stations. That can be a useful intermediate step before another transit stop gets built.