Motorists who drive cars that were first registered before 2001 are unlikely to be aware of how much CO2 their vehicle emits.
A car’s V5 document (sometimes referred to as the logbook) details the amount of CO2 the vehicle emits per kilometre, but this is not the case for vehicles registered before 1st march 2001.
How to calculate CO2 g/km from mpg
If you know a car’s mpg figure, you can use a simple calculation to work out its CO2 g/km figure.
The calculation is simple, but you may find it helps to use a calculator.
|How to calculate your cars CO2 emisions||Knowing only its mpg figure (in this example the car does 40mpg)|
|For petrol engines divide 6760 by 40 (the car’s MPG)||169|
|For diesel engines divide 7440 by 40 (the car’s MPG)||186|
|A petrol-engined car that does 40mpg has CO2 emissions of||169g/km|
|A diesel-engined car that does 40mpg has CO2 emissions of||186g/km|
A spokesperson for the Environmental Transport Association (ETA) said: “Now that road tax is calculated on the basis of CO2 emissions, an increasing number of people know how their car emits, but this may not be the case for the owners of older cars.”