When you make something more available/cheaper, overall usage often goes up. Overall energy use is an important metric regardless of energy per task. Airplane

When you make something more available/cheaper, overall usage often goes up. Overall energy use is an important metric regardless of energy per task. Airplanes are WAY more efficient per passenger than they were in the past, but it's still valid to express concern over the energy usage and pollutants of air travel with so many more routes being flown.