Top 100 most fuel-efficient cars - family

Want to save fuel and cut down your CO2 emissions? The DTI has just unveiled the “Act On CO2” initiative to encourage car buyers to purchase more fuel efficient motors. Auto Express has conducted its own research to find Britain’s 100 most economical motors.

The tests were conducted on public roads and take into account traffic conditions, weather, types of road and all the other variables that influence your mpg. Ten classes of cars were tested, from city cars to SUVs and family saloons to MPVs.

Top of the executive chart was the Mercedes E220 CDI which managed to hold off the challenge of the BMW 525d by returning 37.1mpg. That was still 17 per cent behind official claims, though. The Citroen C6 almost matched the government’s figure of 32.5mpg, but that was only good enough for seventh spot.