No, this post is not an advertisement for a new car only slightly different than last year’s edition. It’s a suggestion for a new design feature on cars that would help you drive more efficiently and save money on gas, while improving your health.

Premise 1: Accelerating on a bicycle is hard–you have to pedal.

Premise 2: Accelerating in a car is easy–you just push your foot down lightly.

Conclusion 1: Compared to bicyclists, drivers don’t mind needless acceleration. What this also means for driving, where you have a route of fixed length, is that drivers don’t mind braking.

For example, on a bicycle I will often slow down well ahead of a red light, so that I can coast slowly until it turns green. But when I drive, usually I will maintain my speed, stop at the light, and then re-accelerate from zero. Drivers start-and-stop more than necessary, especially in cities. Hypermilers have already discovered large inefficiencies in driving behavior, but it’s highly effortful to consciously change how you drive and for most drivers this is unintuitive. The Economist points to a product that promises 30% gains in efficiency from similar changes in behavior.

Solution: Change the automobile interface to make acceleration difficult, like on a bicycle. You wouldn’t be powering the car, but you’d have to be pedaling for the car to go–and you could even make it harder to go uphill. You’d have to change the layout of the car a little bit, but technically I’m sure it’s possible. This would make intuitive driving more efficient, because people are lazy. So you’d be saving gasoline and helping people improve their health.

Edit (2021): I think this post displays a very 2013-era approach to “nudging” that I now mostly disavow.