Note: Numbers represent estimated Exajoules. Source: adapted from Intergovernmental Panel on Climate Change (2014) Climate Change 2014: Mitigation of Climate Change.
The above chart depicts the respective share of energy consumption by type of fuel, transportation mode, type of transport (passenger or freight), and the level of energy efficiency. It also depicts the primary energy flows between sectors. Oil-related fuels accounted for 94% of the energy used by transportation modes, with gasoline being the most used fuel (42.5%; 39 Exajoules), followed by diesel (34.5%; 32 Exajoules) heavy oil, biofuels, and kerosene (21.8%; 20 Exajoules). Electricity and gases (e.g. LNG) account for marginal use as fuels. Gasoline is mainly used for light road vehicles (cars and vans) for passenger transportation. Diesel is the prevalent fuel for heavy road vehicles for freight transportation. Water transportation relies on heavy oils, and most of the fuel is used for freight transport. Kerosene is the primary fuel for air transport, mostly used to carry passengers. The energy conversion level for the transport sector is around 32%, which is higher for freight transport than passenger transport.