Car manufacturers have gotten the word that "green" is in.
Though most of what was on the floor at this year's North American International Auto Show still run on fossil fuel and spew some level of pollutants into the atmosphere, the car makers had plenty to show that gives at least a glimpse of a cleaner, greener future.
Though a few of the vehicles they showed are ready to take to the streets, some are concepts that will be a long time coming, if indeed they ever arrive in dealer showrooms.
They include hydrogen fuel-cell vehicles whose development hinges on getting a refuelling infrastructure in place to provide the necessary hydrogen. Some experts predict mass use of hydrogen vehicles is at least two decades away.
But these fuel-cell vehicles are touted as the best solution in the long run to decreasing the use of fossil fuels and eliminating noxious tailpipe emissions. The only emission from the exhaust pipe of a hydrogen-powered vehicle is water.
One such concept shown by Chrysler was the Chrysler ecoVoyager, a four-door passenger vehicle that looks like a cross between a sedan and a minivan.
The elegant ecoVoyager, with doors on each side that open in opposite directions, runs on an electric motor powered by a hydrogen fuel cell. It has a range of 480km between fill-ups.
Chrysler also unveiled the Dodge ZEO, a four-passenger sport wagon that runs on electricity, using a 200-kilowatt/250-horsepower motor that can propel the car from zero to 96km/h in less than six seconds. It has a cruising range of 400km, but must be recharged from an external power source.
More practical in today's market would be the third Chrysler concept, the Jeep Renegade. This two-seater is a diesel-electric hybrid that has electric drive motors at all four wheels, a battery pack under the floor, and a small, clean-burning diesel engine that is used not to drive the wheels, but to recharge the batteries.