Toyota Prius

No fuel economy test would be complete without a hi-tech hybrid – and the Toyota Prius is one of the best in the business. Mixing an efficient petrol engine with a powerful electric motor, it aims to deliver diesel-like fuel returns.

On paper it impresses, with 72.4mpg combined economy and 89g/km of CO2 – lower than most eco superminis. What sets the Toyota apart is the way its drivetrain performs. Be gentle with the throttle and you can travel over a mile on electric power alone. If you need more pace, the 1.8-litre petrol engine fires into action. Getting the best out of the car takes practice, but will slash your bills. Plus, the Prius is practical and well equipped.