Combustion road vehicles: Overview
The engines that move most of the world's people and goods
The engines that move most of the world's people and goods What this tile covers Cars, trucks and buses burning petrol, diesel, CNG or LPG. Share of use 20% share of final energy use (2019)Share of world total final energy consumption (about 435 EJ, calculated: motor systems 13,462 TWh are 53% of electricity, so about 25,400 TWh or 91 EJ, and electricity is about 21% of final energy) that passes through this device or is used by this sector, latest year available. Electricity-based devices use electricity's 21% share of final energy (IEA WEO 2025). Overlaps between devices and sectors are allowed and noted. Road transport used 49.2% of final oil, and oil was 40.4% of final energy in 2019, so about 19.9% (calculated). Excludes road biofuels and gas; overlaps engines. Source: Key World Energy Statistics 2021, International Energy Agency.
Key facts
| Chain | Chemical → heat → mechanical (pistons) → kinetic |
| Typical efficiency | About 25-30% (petrol engine) |
Included from the reference tables
- Petrol car
- Diesel truck and bus
- CNG and LPG vehicles
Linked to the material world
Oil Crude oilAlso in Transport systems
EV Electric and hybrid vehiclesRail Rail tractionJet Aviation propulsionShp Ship propulsionRkt Rockets and human powerExplore paths from here
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