In the US, traveling by car uses more than double the energy you need to fly---unless you're behind the wheel of a new hybrid. When I moved to San Francisco from New York last year to join WIRED, my new boss scolded me for flying instead of enjoying an epic road trip. (Are you driving cross-country? he implored.

Whether driving or flying is more energy-efficient depends heavily on the distance of the trip and the number of passengers in the vehicle. On a strictly "per passenger mile" basis, modern commercial flying is often more efficient than a single person driving a standard gasoline-powered car for long distances, as airlines maximize efficiency by filling hundreds of seats and flying at optimized altitudes. However, for shorter trips (under 300 miles), driving a fuel-efficient or electric vehicle is typically better because airplanes consume a massive amount of fuel during takeoff and climb. Furthermore, the "efficiency" of driving scales significantly with occupancy; a car with four passengers is far more efficient than a plane, as the energy cost is shared. In 2026, with the rise of electric vehicles and more fuel-efficient jet engines like the LEAP-1B, the gap is narrowing. Generally, if you are traveling alone over a long distance, flying might have a lower energy intensity, but carpooling in a modern vehicle remains the greenest way to travel on land for groups.