How things work

Hybrid Electric Vehicles
Hybrid vehicles—automobiles that use multiple power sources—are all around us. Mopeds—use a gasoline engine and the muscular strength of the rider—were perhaps the simplest hybrid in India for long years. However, there's a lot of interest around hybrid cars. In India, Toyota has launched its hybrid Prius recently, and GM plans to get the Volt by the year-end.

These are cars that use a mix of energy sources, typically electric motors with traditional gasoline engines. They are preferred more than electric cars, as the latter have speed limitations and need to be recharged often.

Hybrid electrical vehicles can be broadly classified into three types—parallel hybrids, series hybrids and parallelseries hybrids.

In parallel hybrids like Honda's Civic, the gasoline engine and the electric engine both can simultaneously transmit power to drive the wheels. In the series hybrids, only the electrical engine powers the wheels. The gasoline engine in turn powers the electrical motor and recharges batteries. Parallel-series hybrids can operate either in series or parallel modes.

Some hybrids are also "smart" cars—when the car brakes, the kinetic energy produced is captured and used to charge the battery systems.