2009 Edmunds Fuel Sipper Smackdown: Hybrids Versus Diesel and Mini

2009 Edmunds Fuel Sipper Smackdown: Hybrids Versus Diesel and Mini

The fuel economy rule of thumb used to be that a full hybrid like the Toyota Prius was great for city driving but not so much better than other cars on the highway; that smaller cars were more fuel efficient than larger cars, and that diesels kicked butt in mileage contests.

Edmunds.com's  crack(ed) team of testers set out last month to see if that's all still true with the new crop of cars and came to some surprising conclusions in what is becoming our annual Fuel Sipper Smackdown.

Over two days and 700-plus miles of driving, from Southern California to and around Las Vegas and then back, the team put the 2010 Ford Fusion hybrid, 2010 Honda Insight, 2009 Mini, 2010 Toyota Prius and 2009 Volkswagen Jetta TDI through a series of driving conditions, tracked fuel costs and computer CO2 output. 

You can read the results here, and watch the video, above, for a 5-minute summary, but we'll give you the boil-down now:

The 2010 Prius, with an overall fuel economy of 47.6 mpg won every category and, surprisingly, did it while maintaining a pretty consistent level of fuel efficiency - no wild swings between the city, backroads and highway tests.

The Honda Insight finished second overall at 42.3 mpg, followed by the Jetta TDI at 38.1 mpg, the Ford Fusion at 37.3 mpg and the Mini at 34.5 mpg.

John O'Dell:  is an AutoObserver Senior Editor. Follow @AutoObserver on Twitter.