Fuel Efficiency
The energy lost when a tyre is moving is described as 'rolling resistance' and has a direct impact on fuel consumption and the environment. The tyres on a car can affect its fuel economy by 20%. The lower the rolling resistance, the tyre less energy is lost - reducing fuel consumption and CO2 emissions.
Putting the scores into perspective, if fitting the worst scoring tyres in this category, you could end up using 6 litres more fuel every 625 miles than if you fit 'A' rated tyres - so, potentially, 'A' rated tyres could save you enough in fuel bills to buy a new set of tyres!