The paycheck giveth. The gas pump taketh away

Here is an artcile about Hybrid cars, which could be our future(hopefully):

The basic problem with automobile gasoline engines is that, to let you blithely roar down the highway, they have to be designed for peak power demands. So, for crawling around the city, they're grossly inefficient. (For waiting at red lights, they are infinitely inefficient.)

In response, hybrids use a battery-powered electric motor in low-power situations, and a gas engine in high-power situations, switching back and forth automatically. The gas engine is simply switched off at red lights, and is often designed to operate in a narrow power range when it is switched on, making it more efficient. The battery is recharged by the gas engine. Generators attached to the brakes can also turn some of the braking momentum (normally lost as heat) into electricity for battery charging.

Read on here...Hybrid cars.