Preparing for the Impact of Driverless Cars


The buzz has been building about driverless cars for a while now, and this week I want to talk about a couple of new articles on the topic followed by my own thoughts.  The first is a McKinsey article based on MIT research:

Full speed ahead: How the driverless car could transform cities

"By combining ride sharing with car sharing—particularly in a city such as New York—MIT research has shown that it would be possible to take every passenger to his or her destination at the time they need to be there, with 80 percent fewer cars

Clearing the roads of four out of five cars has momentous consequences for cities, by measures such as environment, traffic, efficiency, and even parking. In most cities, for example, designated parking accounts for a huge amount of land, which ends up being useless for most of the day. With fewer cars, much of this space could be freed for other uses. Such reductions in car numbers would also dramatically lower the cost (and related energy consumption) of building and maintaining the roads. One engineering study found that automation could quadruple capacity on any given highway. And, of course, fewer cars also means less noise and a smaller environmental impact. 

Driving patterns of individual cars can be algorithmically optimized as well. Because autonomous vehicles don’t get lost, they create less congestion and shorten travel times. More important, self-driving cars would also make for much safer roads; more than 30,000 people a year die in automobile-related deaths in the United States every year and 1.2 million worldwide."

I do have one quibble with the assertions above: yes, there will be fewer cars, but I suspect there will be a similar number of car *trips* (for example, one taxi providing 20 trips/day instead of 10 owned cars each providing two trips/day), and that means just as much wear and tear on the roads,unless a lot more car sharing happens (i.e. one vehicle carrying multiple people on separate trips at the same time).  More on that later...

The second article is from The Economist and chock full of interesting facts:

  • Cars sit idle 96% of the time.
  • Google thinks self-driving taxis could have utilizations of 75%+.
  • Stanford estimates we'll need 70% fewer cars to provide the same trips.
  • "The idea that autonomous vehicles will be owned and used much as cars are today is a “tenuous assumption”, says Luis Martinez of the International Transport Forum, a division of the OECD, a think-tank. Fleets of self-driving vehicles could, he says, replace all car, taxi and bus trips in a city, providing as much mobility with far fewer vehicles. An OECD study modelling the use of self-driving cars in Lisbon found that shared “taxibots” could reduce the number of cars needed by 80-90%. Similarly, research by Dan Fagnant of the University of Utah, drawing on traffic data for Austin, Texas, found that an autonomous taxi with dynamic ride-sharing could replace ten private vehicles. This is consistent with the finding that one extra car in a car-sharing service typically takes 9-13 cars off the road. Self-driving vehicles could, in short, reduce urban vehicle numbers by as much as 90%."
  • 94% of accidents are from human error, and these could be eliminated.
  • "A study by the Eno Centre for Transportation, a non-profit group, estimates that if 90% of cars on American roads were autonomous, the number of accidents would fall from 5.5m a year to 1.3m, and road deaths from 32,400 to 11,300."
  • "As well as being safer, self-driving vehicles would make traffic flow more smoothly, because they would not brake erratically, could be routed to avoid congestion and could travel close together to increase road capacity. A study by the University of Texas estimates that 90% penetration of self-driving cars in America would be equivalent to a doubling of road capacity and would cut delays by 60% on motorways and 15% on suburban roads. And riders in self-driving vehicles would be able to do other things. Morgan Stanley calculates that the resulting productivity gains would be worth $1.3 trillion a year in America and $5.6 trillion worldwide. Children, the elderly and the disabled could gain more independence." 
  • "With cars in constant use, much less parking space would be needed. Parking accounts for as much as 24% of the area of American cities, and some urban areas have as many as 3.5 parking spaces per car; even so, people looking for parking account for 30% of miles driven in urban business districts. By liberating space wasted on parking, autonomous vehicles could allow more people to live in city centres; but they would also make it easier for workers to live farther out. If you can sleep on the journey a longer commute becomes feasible, notes Mr Fagnant, who foresees a “simultaneous densification of cities, and expansion of the exurbs”.

Again, I think it's worth noting that even though the number of vehicles drops, the amount of vehicle-miles probably stays pretty steady or maybe even increases as people can be productive on longer commutes.  In essence, there will be fewer vehicles, but they will get used up/worn out much more quickly from their high utilization (similar to buses today), so the car industry may be safe from complete collapse, although it will certainly be massively disruptive.

A key question is how much car sharing will occur, which reduces prices and increases efficiency by picking up and dropping off multiple people along routes.  It can be a bit awkward sharing a vehicle with strangers.  I would not be surprised to see someone like Uber custom design a vehicle with individual personal compartments.  Imagine 5-6 private individual seating compartments in a 6-door SUV-sized vehicle.  When it pulls up, an indicator tells you which door to get into for your compartment, and then alerts you again when it's time for you to get out, based on the destination you put into your smart phone.  Private ride, shared prices and efficiency - best of both worlds.  Mass adoption of shared rides would solve our traffic congestion problems almost overnight.

A couple of additional thoughts: If most accidents get eliminated, do we still need shoulders? Maybe those could be converted to extra lanes?  The same for street parking if vehicles are continuously utilized - long-term those spaces might be convertible to additional lanes, adding surface street capacity.  Or in some cases, it might make sense to expand the sidewalk/public realm into that space instead.

So what should cities be doing now to prepare for this future?

  1. Loosen up or even eliminate minimum parking requirementsnow so available parking starts shrinking naturally over the next few years.  This will also enable greater infill and density in cities as well as supply much-needed new housing stock.
  2. Stop investing in new rail transit - they're not going to be able to achieve their payback before this revolution (if they ever could in any case).  Managed-lane networks are a better investment, as they can be used for buses, HOVs, and toll-payers now, and easily switched over to automated vehicles later.

It's going to be a brave, brave new world...

Tory Gattis is a Founding Senior Fellow with the Center for Opportunity Urbanism, and co-authored the original Opportunity Urbanism studies. Tory writes the popular Houston Strategies blog and its twin blog at the Houston Chronicle, Opportunity Urbanist, where he discusses strategies for making Houston a better city. He is the founder of Coached Schooling, a startup to create a high-tech network of affordable private schools ($10/day) combining the best elements of eLearning, home and traditional schooling to reinvent the one-room schoolhouse for the 21st century. Tory is a McKinsey consulting alum, TEDx speaker, and holds both an MBA and BSEE from Rice University.

By Driving_Google_Self-Driving_Car.jpg: Steve Jurvetsonderivative work: Mariordo [CC BY 2.0], via Wikimedia Commons.

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Heavy vehicles—buses and

Heavy vehicles—buses and trucks—cause the most wear and tear on the roads, not so much cars. Eliminating buses would help but perhaps to go from 75% utilization (according to Google) to 100%, those empty AVs could be utilized to deliver cargo. Just a thought.

Car sharing might initially be along the lines of social networks today. You "friend" people who you're will to share a ride with. In addition I'm sure the car services will offer several levels of vetting. Non-vetted rides though could be in compartmentalized vehicles. Commuting now is "alone time." Non-compartmentalized car sharing would be a big step for most people. It might be a nice change for many.

Watch for local Mothers Against Self Driving™ chapters to start springing up soon after AVs start to gain market share. City centers will be the first to ban self-driving, expanding out to the suburbs, until whole metropolitan areas outlaw self-driving except on Sundays between 8am and 4pm, for those "kooks" who drive for nostalgia's sake. The reduced carnage from automobile accidents will force politicians' hands to gradually ban self-driving.

May you live in interesting times

1. Commuter rail is doomed.
2. By 2060 it will be illegal for humans to drive cars in the USA.
3. More urban sprawl? People do love their acreage.

Dave Barnes

car reduction

If most people continue to commute at the same time how much of a reduction can that lead to in the number of vehicles? Your compartmentalized vehicles seems like they are high end self driving buses. Plausible I suppose as buses do take some cars off the road.