Driving Is Actually Less Energy-Efficient Than Flying

If you've ever wrestled with the moral implications of flying from Washington to Chicago when you could perfectly well drive there, you may be comforted to know that airplane travel actually demands less energy per person, per mile. This hasn't always been the case. But, according to some national data recently compiled by the University of Michigan's Michael Sivak, air travel in the U.S. became less energy-intensive than driving around the year 2000, and it's remained that way ever since.

This chart, compiled from Sivak's data, illustrates the efficiency gains by the two modes of transportation over the last 40 years, measured in BTU per person mile. This takes into account the typical passenger load on domestic flights for all certified air carriers, as well as the number of occupants carried on average by light-duty vehicles. Think of it as the total amount of energy it takes to move one person one mile, by either plane or car (including the energy needed to cool our cars along the way, or to pressurize airplane cabins mid-flight):