Hybrid electric vehicle (HEV) is a vehicle that employs a combustion engine system together with an electric propulsion system. Hybrid technologies expand the usable range of EVs beyond what an all-electric-vehicle can achieve with batteries only.

How do Hybrid electric vehicle work?

Hybrid vehicles have a conventional engine (gasoline or diesel) as well as a large battery and an electric motor, so that the wheels of the car are driven by both an internal combustion engine and an electric motor. There are various arrangements for these two motors. In the parallel hybrid car, both the conventional engine and the electric motor are attached to the driveshaft and the wheels of the car. In the series hybrid car, the conventional engine is used only to generate electricity, which then goes through a wire to an electric motor that drives the wheels. Combinations also exist; for example, the front wheels are driven by a conventional engine and the rear wheels by an electric motor.

The hybrid vehicle typically achieves greater fuel economy and lower emissions than conventional internal combustion engine vehicles (ICEVs), resulting in fewer emissions being generated.

Following features make a hybrid vehicle particularly efficient for city traffic where there are frequent stops, coasting and idling periods.

• Recapturing energy normally wasted during braking etc.
• Shutting down the gasoline or diesel engine during traffic stops or while coasting or other idle periods;
• Improving aerodynamics - improving the shape and aerodynamics of a car is a good way to help better the gas mileage and also improve handling at the same time.
• Using low rolling resistance tires
• Relying on both the gasoline (or diesel engine) and the electric motors

Toyota Motor Corp said that it has developed an advanced new zero-emission fuel-cell vehicle that can run for 830 km (516 miles) on a single tank of hydrogen and in temperatures as low as 30 degrees Celsius below freezing temperature (-22 F).

Toyota has been developing its hydrogen fuel cell technology since 1992 and has announced they’ve created a more efficient version of their Fuel Cell Hybrid Vehicle (FCHV) named the FCHV-adv.

In comparison to the previous FCHV which had a range of 205 miles, it is claimed fuel efficiency has been improved by 25% through improving fuel cell unit performance, enhancing the regenerative brake system and reducing energy consumed by the auxiliary system

Fuel-cell vehicles are widely considered the ultimate longer-term alternative to today’s conventional cars as they run on an inexhaustible and cheaper source of fuel — hydrogen — have no harmful tail-pipe emissions, and do not compromise driving performance.