The transportation of people and goods accounts for about 25% of all energy consumption in the world. Passenger transportation, in particular light-duty vehicles, accounts for most transportation energy consumption—light-duty vehicles alone consume more than all freight modes of transportation, such as heavy trucks, marine, and rail. The United States was the world’s largest transportation energy consumer in 2012, the most recent year with detailed international transportation data by mode. The United States, where on-road passenger travel is especially prevalent, consumed 26 quadrillion British thermal units (Btu), or 13 million barrels of oil equivalent per day (b/d), representing 25% of global transportation energy demand in 2012. Major European countries (those in the Organization for Economic Cooperation and Development, or OECD) and China are also major transportation energy consumers, at 19 quadrillion Btu and 13 quadrillion Btu, […]