If you eliminate parking, what happens to the cars when not in use?
Theyre either circling the block waiting for a rider, creating congestion, or need to be parked somewhere
Shared cars need a WHOLE LOT LESS parking than one-per-person cars. We're going to eliminate a LOT of parking, particularly in the urban core (CBD), where the space can be better used for bike, ped, & bus.
Zipcar already has eliminated a lot of parked, idle cars (but the spaces saved got eaten up by resident permits that are still too cheap and encourage over-parking)
Private cars park something like 22hours out of 24 (and serve 1 person)
Zipcars park something like 18 hours out of 24 (and serve 4 people 4-to-1 reduction in cars resulting in a 4-to-1 reduction in overnite spots required and a reduction from 32 "midday" spot-hours (4x8) to roughly 6 midday spot hours, a 5-to-1 midday reduction)
The same way that a Zipcar's four daily users share one car and one spot, self driving cars will have (say) 10 users each day sharing one car and its one spot. So that's a 10-to-1 reduction in parking demand, and the spot that is demanded is overnight-only (no "downtown" parking needed...so the space can be returned to bus, bike, & pedestrians)
For a self-driving car (or any cheap "Uber" mode)
- When riders are plentiful, they'll be busy carrying them, not parking
- When demand is light, traffic will be light, and prowling won't be congesting.
If they need to park, they can calculate the opitimal blend of parking local, parking remote, or prowling. Either way, they're working hard to not be a zero-occupant-parker.
Cars today park for HOURS. They park for errands. They park for their sole user, waiting to come back.
Imagine, for example that your self driving car has just dropped you at work on Devonshire St. When you step out, it immediately goes into "Uber" mode, and is assigned a fare, and spends your whole working day earning money as a cab, but you and it negotiate the pre-agreed trip home for you. You and 10 people share 1 car and its one spot that day. And at that point, you're better of not owning that car. Just rent, as time share jets are, from a big fleet owner.
Midday, there's no demand...but that also means there's less traffic and not much penalty imposed by letting your car prowl (or it could park someplace outside the CBD where parking prices are lower). Still, it has done its job: 9 other people "shared" your car and their trips produced no demand for parking at all.
Self-driving Ubers will have fully-idle moments. In that moment, the car will pick the most economically efficient activity:
- prowl on less congested streets
- park in an rare-but-expensive spot in the CBD (maybe to refuel/recharge)
- drive further out and park cheaper
- and park with its clones in last-in first-out (LIFO) dead ends that "regular" cars cannot use (because you demand "your" car back) and taxi drivers can't use (because LIFO parking is unfair to human drivers working shifts, but works fine with machines (its how shopping carts work, usually)