A hybrid electric vehicle (HEV) is a vehicle that uses two or more distinct power sources to propel the vehicle. Common power sources include:
• On-board rechargeable energy storage system (RESS) and a fueled power source (internal combustion engine or fuel cell)
• Air and internal combustion engines
• Human powered bicycle with electric motor or gas engine assist
• Human-powered or sail boat with electric power
The term most commonly refers to Hybrid-electric vehicle (HEV) which include internal combustion engines and electric motors.
