Hybrid electric vehicle

A hybrid electric vehicle (HEV) is a type of hybrid vehicle that combines a conventional internal combustion engine (ICE) system with an electric propulsion system (hybrid vehicle drivetrain). The presence of the electric powertrain is intended to achieve either better fuel economy than a conventional vehicle or better performance. There is a variety of HEV types and the degree to which each functions as an electric vehicle (EV) also varies. The most common form of HEV is the hybrid electric car, although hybrid electric trucks (pickups and tractors), buses, boats,^[2] tow trucks,^[3] and aircraft also exist.

Modern HEVs make use of efficiency-improving technologies such as regenerative brakes which convert the vehicle's kinetic energy to electric energy, which is stored in a battery or supercapacitor. Some varieties of HEV use an internal combustion engine to turn an electrical generator, which either recharges the vehicle's batteries or directly powers its electric drive motors; this combination is known as a motor–generator.^[4] Many HEVs reduce idle emissions by shutting down the engine at idle and restarting it when needed; this is known as a start-stop system. A hybrid-electric produces lower tailpipe emissions than a comparably sized gasoline car since the hybrid's gasoline engine is usually smaller than that of a gasoline-powered vehicle. If the engine is not used to drive the car directly, it can be geared to run at maximum efficiency, further improving fuel economy.

Ferdinand Porsche developed the Lohner–Porsche in 1901.^[2] But hybrid electric vehicles did not become widely available until the release of the Toyota Prius in Japan in 1997, followed by the Honda Insight in 1999.^[5] Initially, hybrid seemed unnecessary due to the low cost of gasoline. Worldwide increases in the price of petroleum caused many automakers to release hybrids in the late 2000s; they are now perceived as a core segment of the automotive market of the future.^{[6][7][better source needed]}

As of April 2020^[update], over 17 million hybrid electric vehicles have been sold worldwide since their inception in 1997.^[8][9] Japan has the world's largest hybrid electric vehicle fleet with 7.5 million hybrids registered as of March 2018^[update].^[10] Japan also has the world's highest hybrid market penetration with hybrids representing 19.0% of all passenger cars on the road as of March 2018^[update], both figures excluding kei cars.^[10][11] As of December 2020^[update], the U.S. ranked second with cumulative sales of 5.8 million units since 1999,^[12] and, as of July 2020^[update], Europe listed third with 3.0 million cars delivered since 2000.^[13]

Global sales are led by the Toyota Motor Corporation with more than 15 million Lexus and Toyota hybrids sold as of January 2020^[update],^[8] followed by Honda Motor Co., Ltd. with cumulative global sales of more than 1.35 million hybrids as of June 2014^[update];^[14][15][16] As of September 2022^[update], worldwide hybrid sales are led by the Toyota Prius liftback, with cumulative sales of 5 million units.^[1] The Prius nameplate had sold more than 6 million hybrids up to January 2017.^[17] Global Lexus hybrid sales achieved the 1 million unit milestone in March 2016.^[18] As of January 2017^[update], the conventional Prius is the all-time best-selling hybrid car in both Japan and the U.S., with sales of over 1.8 million in Japan and 1.75 million in the U.S.^[17][9]