After Earth Day, Understand The Transit Compromise To Grasp Efficiency

InnovationTransportationAfter Earth Day, Understand The Transit Compromise To Grasp EfficiencyByBrad Templeton,Senior Contributor.Forbes contributors publish independent expert analyses and insights. Brad Templeton, who was early at Waymo, covers transportation's futureFollow AuthorApr 23, 2026, 02:45pm EDT--:-- / --:--This voice experience is generated by AI. Learn more.This voice experience is generated by AI. Learn more.Previously, transportation planners have thought bigger was more efficient. It didn't work, but in the world of self-driving, a different answer is possible: Less is moregettyBigger isn’t more efficient when it comes to transportation.A large fraction of our energy use in modern society goes to transportation, and most of our oil. About 25% of greenhouse gas emissions come from transportation, so it’s naturally one of the top topics for yesterday’s Earth Day. A common thrust of earth day messages is to use more transit. The problem is that in the USA, transit is surprisingly energy inefficient. Many people are unaware that U.S. systems almost universally use more energy per passenger-mile than the average equivalent private automobile. Often a lot more.One of the biggest questions to address in transportation is why this is, and what can be done to fix it. The proximate cause of this inefficiency is poor “load factor”--how full the vehicle is. While a packed bus or train is efficient, no transit system consists of only full vehicles. Theoretical efficiency is nice, but moving empty seats is not efficient, and so the cause of these empty seats is important.(It should be noted that this is relevant to the debate about transport system design. It is generally more efficient for an individual to hop on an already operating train to take one of those empty seats than to go drive their own car. That doesn’t mean the question of why a transit system does so poorly isn’t important.)Some wake-up numbers are in order. The Dept of Energy publishes...