By making automotive transport easier and more convenient, the obvious consequence is a general increase in automotive traffic. In city centers the worst exter

By making automotive transport easier and more convenient, the obvious consequence is a general increase in automotive traffic. In city centers the worst externality of cars is the space they hog. Self-driving electric cars won't fix that; instead they are likely to increase the utilization of that space: unlike with humans where congested traffic suggests the drivers to look for alternative options such as mass transit, an empty car doesn't mind waiting in traffic by itself. Suburbia is likely to expand further because if you can work a few hours in your car that means you can afford to live further away in a cheaper location. And school kids can get to school in a car by themselves, so the total number of automotive miles is likely to go up.