Real-world tests have shown hybrid cars fall well short of their claimed emissions and fuel efficiency figures, raising the question of whether the technology has so far been anything more than a very effective marketing gimmick.

Some diesel-powered cars also received bad marks in the review, showing much higher emissions and poorer fuel economy, just like the hybrids. Honda's Civic Hybrid, Lexus's GS450h and Skoda's Fabia Greenline were the three models to get the 'gimmick' label by the testing publication, Auto Express.

The Honda Civic Hybrid, for example, scored a real-world output of 171g/km CO2 versus a claimed 109g/km, a difference of 57% - well outside the range of a typical margin of error. Lexus's luxury hybrid similarly scored real-world fuel consumption of 26.7mpg, falling 34% short of its claimed 35.8mpg. Skoda's Fabia Greenline scored worse than the SEAT ECOmotive and VW Polo BlueMotion that used the same engine, and was knocked for that failure.

Still, five models in total managed to get a green rating despite failing to live up to their manufacturers claims. Ford's Focus with the ECOnetic treatment, the Mini Cooper Clubman D, Toyota Prius, Seat Ibiza ECOmotive and Volkswagen Polo BlueMotion all rated well enough to be considered somewhat eco-friendly.

Via: TheTruthAboutCars