Exactly 3 out of 4. 75% of all new cars registered in France last month were diesels. I know gas engines are getting better and better. Engines like the TSI from Volkswagen or the Ecoboost from Ford are great units, but the latest diesels are so good, I’m sure they will retain the lead for many more years. Just look at this BMW 520d EfficientDynamics Edition, it’s the most fuel-efficient 5-series. Its engine is a modest 2-liter inline four, giving 184-hp and 280-lbs-ft of torque. Enough for a family sedan. Top speed is 143-mph, and the car doesn’t need more than 8.2-seconds to go from 0 to 62-mph. This is much better than what a Prius can do, yet it hardly needs more fuel.

On the official European tests, this BMW’s rated at 52-mpg. A Prius is rated at 59-mpg on the same test. That’s the result of a modern turbo-diesel engine, with all the latest tricks in fuel efficiency optimization. There’s a Stop & Start system to prevent the engine from idling when the car is stopped. The alternator then is an intelligent unit only taking power when the car’s decelerating. The wheels are highly aerodynamic, and a lot of work has been done to make the car slippery. Of course, the car’s pretty long-geared. The transmission is a 6-speed manual. At 80-mph, the diesel’s just below the 2000-rpm mark. And it’s fine, the car’s been fitted with a a centrifugal pendulum absorber which reduces irregular running at low engine speeds for greater refinement! Redline is at 4500-rpm, with peak torque at 1750-rpm, you can drive at 1500-rpm in sixth gear. It’s comfortable and fuel-efficient. Too bad only Europeans can benefit…