Share a Car, Save the Planet

Share a Car, Save the Planet

Share a Car, Save the Planet

A recent study has found that increased vehicle access in urban areas might actually reduce fuel consumption – as long as those cars are shared, not individually owned.

It may seem counterintuitive that putting more drivers behind the wheel could have an environmental benefit, but Elliot Martin and Susan Shaheen at the University of California Transportation Center say that car-sharing services such as Zipcar, Car2Go and Relay Rides are most often used by those looking to get rid of a car.

Therefore, car sharing reduces overall vehicle ownership, takes older cars off the road and helps individuals move away from car-dependent lifestyles – all trends that reduce tailpipe emissions.

In a study of 6,281 car-sharing households, the authors found that 80 percent of those surveyed moved from owning a single car to owning zero cars after joining a car-sharing service. The cars that folks got rid of tended to be more than a decade old and averaged 23 mpg. Compare that to the vehicles in a car-sharing fleet, which average 33 mpg and tend to be low-tailpipe-emissions hybrids or gas-sipping compact cars.

Aside from those study participants who ditched car ownership altogether, Martin and Shaheen also found that access to a shared car often allowed households to avoid purchasing a vehicle, or a sell a rarely used second car that took up a parking spot and cost money to keep on the road. While it's difficult to measure cars not purchased, they estimated that each car in a shared fleet represented between nine and 13 individually owned cars that were not on the road.

"Car-share households exhibited a dramatic shift toward a carless lifestyle," the study authors wrote. "The vehicles shed are often older, and the car-sharing fleet is an average of 10 mpg more efficient than the vehicles shed."


"While this study shows that car-sharing has already had a significant and measurable impact in many metropolitan regions, industry growth into new markets may produce much greater environmental benefits in the future," they wrote.

Photo: Flickr/crschmidt