A hybrid electric vehicle (HEV) is a vehicle using an on-board rechargeable energy storage system (RESS) and a fueled power source for vehicle propulsion. The different propulsion power systems may have common subsystems or components.
A hybrid vehicle provides better fuel economy than a conventional vehicle, because the engine is smaller and may be run at various speeds, providing more efficiency. Other techniques may be used to recover or reduce waste energy (such as regenerative braking and shutting down the combustion engine). From Wikipedia, the Free Encyclopedia
