Driverless Cars: Boon or Bane?

The good:Driverless vehicles are expected to help children, the blind, the elderly and others who currently cannot safely drive themselves.

The not so good: Smarter driving will lead to more driving, because smarter driving reduces the cost per mile of vehicle usage. The end result of additional driving could be more traffic and more aggregate fuel consumption.

The good:Driverless vehicles are expected to help children, the blind, the elderly and others who currently cannot safely drive themselves.

The economics: Fuel and wear and tear cost roughly 50 cents a mile, which is why employers reimburse employees for job-related personal vehicle usage at about that rate. At an average speed of 30 miles an hour (including stops, traffic conditions and so on), each mile takes two minutes of driver time. For those who value their time at more than $15 an hour, the time cost of the trip exceeds the combined fuel and wear and tear costs.

The behavioral response: Research has shown that cutting travel costs through reduced gas prices causes people to drive more, for example by eschewing carpools and public transportation. A driverless car should also cause people to use their vehicles for more miles, because they could use their time in the car to sleep, work, watch television, read a book and do other things they might normally do at home.