The BMW 320d EfficientDynamics combines 68.9 mpg and 109 g/km CO2 emissions with a 0-62 mph time of 8.0 seconds and 137 mph.

The Volkswagen Golf BlueMotion emits just 99 g/km CO2, equivalent to 74.3 mpg, and is an incredibly refined family hatchback.

The Toyota Prius has super-low emissions of just 89 g/km CO2 thanks to its petrol-electric hybrid drivetrain.

The Volkswagen Polo BlueMotion can achieve 80.7 mpg combined along with emissions of just 91 g/km CO2.

The new BMW 520d manages 57.6 mpg, with emissions of 129 g/km CO2, highly impressive for this class of car.

The Volkswagen Scirocco is a refined and practical sports coupe that is also great to drive and capable of 55.4 mpg.

The Toyota Auris HSD is noteworthy for being the first car in this class to get a full hybrid system, matching the 89 g/km CO2 of the Prius.

The BMW 118d Coupe offers entertaining rear-wheel drive handling along with fuel economy of 62.8 mpg.

The Volvo V50 DRIVe has all the practicality of an estate with 74 mpg economy and emissions of just 99 g/km CO2.

The Honda CR-Z deserves a mention as it is the first 'sporty' hybrid, offering fun along with 56.5 mpg and 117 g/km CO2.