General Motors' Saab division went fossil-fuel free for the introduction of its BioPower Hybrid Concept at the 2007 Detroit Auto Show. Built as a 9-3 convertible, the BioPower Hybrid combines an electric motor with a 2.0-liter turbocharged four-cylinder engine that runs on bio-ethanol alcohol, called E100. E100 contains no gasoline and allows the engine to produce 260 horsepower.

Electric propulsion comes in the form of GM's "2-Mode" hybrid technology. This system allows the car to run on one or both of its power sources and requires no plug-in charging. Energy storage for the electric motor comes from a 300-volt lithium-ion battery that stores beneath the trunk floor and takes up no additional cargo space. The car has a "Zero Mode" button on the console that allows it to run exclusively on electric power at speeds below 30 mph. Zero Mode provides a range of between six and 12 miles and automatically restarts the gas engine when the car goes above 30 mph or has a low battery charge. There was no word from GM as to whether or not the BioPower Hybrid will see production.

Saab BioPower Concept