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by majormajor 1430 days ago
Is it weird? I think there's two big things that explain why it's not weird:

1) How expensive and disruptive to build would "good transit" actually be?

2) How much do people appreciate more direct point-to-point transportation?

This incident occured in a town of 51,000 people with a density of 1,700/sq mile, that looks like a suburb of Salt Lake City which itself has 200,000 people with a density of 1,800/sq mile.

What's the cost and timetable for turning that into a transit-friendly city even if everyone wanted to have smaller homes in a presumably-more-dense footprint?

On the other hand, self-driving cars would sit on top of existing infrastructure to enable even more personal privacy and land use. So even if people were 50/50 which way to go, the latter would likely be far cheaper.

If you go back 100 years and prevent cars from ever be mass-produced, yeah, American cities would've grown and suburbanized in a more British, rail-oriented way. But reversing that would be far, far harder.

2 comments

So…… 25 sq miles. Let’s assume a 5 mile x 5 mile grid. Let’s put a bus route every half mile. That’s 20 bus routes. Let’s run a bus on each route every 15 minutes…. The buses run at an average speed of say 20 mph. So each bus takes 20 minutes to traverse the route in one direction. You would need 2 buses per route. That’s 40 buses. Let’s say it costs $100 per hour to run the bus. (Googled it). So that’s $4000/hr to run the entire system. Let’s run the system 16 hours a day. 4000 * 16 = $64000 per day. $23 million dollars a year. The 51,000 population would have 17,000 cars. 17,000 * $5000 = $85 million. So it would be much cheaper to have a bus system….
Where'd this $5000/car(/yr?) number come from? Total cost of ownership for a car is far less than that. You can only really get to $5k/year through very high depreciation, and people buying those kinds of cars won't be riding your busses anyway.

Also, $100/hr to run a bus is probably a fine operating cost number, but you do have to buy the bus (capitalized cost) and take the depreciation hit just like cars.

The total cost of ownership includes gasoline, repairs, insurance, road tax as well as depreciation. The $100 per hour includes the cost of buying the bus.
Look at [1] and you see it's the average across the US. It's more expensive than that in many states. Unless you're discounting the purchase price/monthly loan payment/lease price.

[1]: https://www.move.org/average-cost-owning-a-car/#data

Key word there is probably average. Median would be more interesting.
New Mexico is sitting at the median (spot 25, so not quite, need to average out the two middles) at $5,063.78.
The median of a list of averages is not the median of the population.
I don't think I've paid (the equivalent of) $5000 for every car I've ever owned, in total.
This analysis reeks of confirmation bias. You don't need one personal car for every 3 people if you were to comparing busses with self driving cars. You would have a fleet, just like you do with busses. Here is something posted a couple days ago:

https://www.npr.org/2022/07/19/1111765630/on-demand-shuttles...

15 minivans replaced 6 busses, at a cost of 1.6 million to 1.3 million per year - but with much better coverage than the busses.

Of course this equation will look very different in big cities where economies of scale from mass transit kick in, but hey, small cities need transit too.

There are no self driving cars … why would I compare buses to them?

But the minivan link was interesting.

Fleets of cars would require additional infrastructure being built (specialized parking structures, staging areas, etc) so would increase costs. At this point we're also talking about the theoretical extension (fleets) of a theoretical concept (self-driving cars) so basing this execution in reality seems fraught.
The "self-driving" cars would be piggy-backing on the massive subsidies provided to driver-driving cars and infrastructure demanding them, siphoned away from public transit.