The cost of hybrids continues to fall, with the 2010 Honda Insight going for less than $20,000 and the 2010 Prius starting at $22,000, with a cheaper version in the works.

Plug-Ins On Horizon

And the move continues toward producing more plug-in hybrids, with President Barack Obama is pushing to put 1 million plug-in hybrid cars on the road by 2015.

Plug-in hybrids allow motorists to drive a limited number of miles on battery power before the engine switches over to run on gasoline or other fuels. A driver can plug the car into a wall outlet at night and be ready to go electric again in the morning.

General Motors and Nissan will become the first automakers to offer mass-produced, plug-in vehicles available for sale in the U.S. in late 2010 with the Chevrolet Volt and the Nissan Leaf.