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by njarboe 2870 days ago
The more "mass" the transit the harder it is for the vehicle to go exactly where all the people on it want to go. Subway, maybe walk a 1/2 mile, bus somewhat less but lots of stops, individual road transport, very close.

An auto-car just sitting costs almost nothing per hour (capital cost, but very little other cost), so you can have lots of them everywhere. Pickup time can be very short. I almost never used taxis in my town because of long and unreliable pickup times. Use uber all the time now. I still own a car, but if I did not have off street parking like many in my neighborhood, getting rid of it would be a no-brainer.

2 comments

> An auto-car just sitting costs almost nothing per hour (capital cost, but very little other cost)

I'm not sure it's fair to dismiss capital cost parenthetically as part of "almost nothing". Maybe if the auto-cars were retrofitted 10-15 year old vehicles and the retrofitting cost a fraction of the vehicle's value, I'd agree. However, if they're all brand new (and even electric, where the TCO is weighted toward capital and away from operating costs), I say it's far from almost nothing.

Additionally, you go on to point out:

> if I did not have off street parking like many in my neighborhood, getting rid of it would be a no-brainer.

Therein lies a cost of "just sitting" that is routinely brought up in any car vs public transit (or other alternatives like bicycles or walkable designs) conversation.

The denser the area, the higher the cost. I suspect that if you did not have off street parking due to density, the parking portion of the "just sitting there" cost included in the pricing of the auto-car would make it no longer a no-brainer.

Where auto-cars could at least gain some space efficiency is in being able to park bumper-to-bumper and with minimum side clearance, since there would be no need for a human to enter or exit while it's in storage.

Auto cars can also drive away from expensive parking when not in use. Lots of Uber drivers live in Sacramento but work in SF 80 miles away.

Maybe if interest rates go up capital costs will be an issue, but using a 100k car paying 4% interest is $4000 a year or about $0.50 per hour. When not moving there is basically no wear and tear or fuel costs. Almost nothing compared to paying a driver.

> Auto cars can also drive away from expensive parking when not in use.

Driving away is, of course, not standing still. That increases the cost, but, perhaps more importantly, increased latency (or, rather, jitter).

They need not be stored in the most expensive, densest areas, but, for those who want to get rid of car ownership, that non-zero cost (especially if borne by the public with free on-street parking) isn't likely one they're willing to ignore.

> about $0.50 per hour.

A car sitting idle for 9 hours per day and averages 30mph while driving adds 1 cent per mile. A car sitting idle for 18 hours adds 5 cents per mile.

The former may be almost nothing, but the latter isn't.

> Almost nothing compared to paying a driver.

I still disagree, but that's just semantics.

Depreciation and utilization rates need to be incorporated.

If interest + depreciation is about $9K/yr, that's $25 a day, which means if you drive 8 hrs a day and have a 58% utilization rate, is $5.38/hr which is not all that far from what Uber drivers net. At 30 mph, it's 18 cents added per mile.

A self-driving car could perhaps operate more than 8 hours a day, but that doesn't mean that customers will be equally available at all hours.

I strongly suspect that when you do a proper analysis, self-driving cars are just competitive and not hugely cheaper.

> Depreciation and utilization rates need to be incorporated.

That's tough to do, since we don't know either one. I suspect there's also a (perhaps incorrect) assumption that an unused auto-car will be "just sitting there" rather than moving, in which case utilization is, effectively, 100%.

That's not possible with a human driver in at least the case of a long one-way trip. However, with auto-cars, this could end up merely increasing the capital cost at the expense of unpaid/empty trip cost.

The extra cost is something I mentioned in my latency/jitter comment, wrt cheaper parking.

> $5.38/hr which is not all that far from what Uber drivers net

I didn't check your arithmetic, but, if so, it's is quite far from the fair/livable wage of $15/hr that at least I've been assuming for this conversation.

The fact that rideshare services are currently, effectively, paying much less is certainly an indication that even that may not be enough to lure people away from ownership.

Utilization rate means percentage of time that is billed to a customer, I believe/presume. Whether a car is moving is not the same thing. The issue is whether it is on the clock or not, and given that computers already are used to match passengers and route cars, I'm not clear on why we would expect a drastic increase. Currently, we see 50-60%. Even a perfect routing algorithm can't make it 100%, because there are only so many customers, so things like how many cars there are per customer matter. If you reduce the cars per customer, service suffers. If you increase the number, utilization falls.
Seems like depreciation (assuming straight line over 20 years) is going to roughly double that figure.
Nice inclusive term, individual road transport can only mean bicycle since that is the only way you can get enough parking close for everyone.
auto-vehicle? I'll try to use that. A much better word especially since car=always bad for some people.

Bicycle parking is also a problem in many areas that have a high density of bicycle users. See Amsterdam train stations or apartment buildings where you have to store your bike in your 600sqft apartment.

Walking is really the best although these new electric skateboards seems to be almost totally portable and storable.