OWINGS MILLS, MD --- "MotorWeek," television's longest-running automotive series, and Cars.com recently teamed up for the "Power & Economy Drive" to determine which shade of green makes the most sense for consumers. The winning vehicle was the 2010 Toyota Prius.

"The Power & Economy Drive" is featured on the "MotorWeek" episode that begins airing on PBS Saturday, Sept.12.

"We hear a lot about fuel economy these days, but we wanted to know which cars deliver fuel efficiency without compromising power and performance," said John Davis, "MotorWeek" host and executive producer. "'MotorWeek' and members of Cars.com's editorial staff got behind the wheel of three hybrids, two clean turbocharged diesels and a compact car to find out what's behind the fuel economy numbers." 

MotorWeek and Cars.com took six cars with the highest government fuel economy ratings to the mountains of Western Maryland for a typical weekend family outing. The gas sippers tested were the 2010 Toyota Prius, 2010 Honda Insight, 2010 Ford Fusion Hybrid, 2009 Volkswagen Jetta TDI, 2010 Audi A3 TDI, and the 2009 Smart Fortwo. 

Each car was equipped with a data recorder for monitoring driving and engine performance. The cars were put through the paces, covering 500 miles of extremely challenging terrain over three days. The team assessed overall comfort, performance, handling and of course, fuel economy. 

"We found the Prius, in the end, offered a really top-notch interior, a peppy ride and great mileage," said Patrick Olsen, editor-in-chief of Cars.com. "There were several close competitors, but the Prius's new look and frugal ways won us over." 

The full report airs on "MotorWeek" episode 2902. Here are the results of the "MotorWeek" and Cars.com "Power & Economy Drive" by the numbers: 2010 Toyota Prius (drive mpg of 49.2, EPA mpg of 50.0), 2010 Honda Insight (drive mpg of 40.5, EPA mpg of 41.0), 2010 Audi A3 TDI (drive mpg of 38.2, EPA mpg of 34.0), 2009 Volkswagen Jetta TDI (drive mpg of 36.2, EPA mpg of 34.0), 2009 Smart Fortwo (drive mpg of 35.3, EPA mpg of 36.0) and 2010 Ford Fusion Hybrid (drive mpg of 32.9, EPA mpg of 39.0).