There is growing interest in developing hybrid electric-internal combustion eco-cars, or supercars, getting 64-128+ kilometers per liter, that is around 150-300+miles per gallon. They get most of their power from a small hybrid electric/fuel engine that makes its own electricity and uses a small battery or flywheel to provide the extra energy needed for acceleration and hill climbing.

The small gasoline engine keeps the batteries charged, thus reducing the number of batteries needed and greatly increasing the range. If needed, the electric engine could also operate emission-free in urban areas. Canada’s HydroQuebec has developed a hybrid car system that places small electric motors in all four of a car’s wheels.

In 1997 Toyota developed a hybrid electric/gasoline vehicle that is twice as fuel efficient as an equivalent gasoline-powered car, while significantly reducing air pollution emissions. This car, called Prius, is on the market in Japan and gets 28 miles per liter. 1n 1999, Honda began selling a fuel efficient, hybrid-engine car.

A major limitation of gaseous fuels such as natural gas and hydrogen is that they require fairly heavy and bulky fuel tanks, which reduce efficiency and range. However, a hybrid car might be able to overcome this problem by going 700 kilometers on just 5.6-11 liters of gas. » Read more: Development of Eco Cars