Buying a new car

Check to see if the car you are interested in has a diesel or hybrid version as these often have much lower CO2 emissions than the petrol engine versions.

In general, small cars and cars with smaller engines produce less CO2. There can also be a big difference in emissions of cars in the same market category (e.g. family cars, MPVs), so make sure you compare before making your purchase.

Emissions that affect air quality, such as NOx and particulates are higher in diesel engines, and these should be considered, particularly if you drive mainly in urban areas.

However modern diesels are getting cleaner all the time and many have the option (or as standard) of a DPF (a diesel particulate filter) which greatly reduces emissions of fine particles from the exhaust.

Diesel engine and hybrid cars generally cost more to buy but are cheaper to run than petrol engine cars.

What are the lowest emission cars available in the UK?

You can find information about the lowest emission cars on the new car market in the Best on CO2 Rankings at the Department for Transport's ACT ON CO2 pages. You can choose what class of car you want (e.g. small family, estate, MPV), the gearbox (manual or automatic) and the fuel type (e.g. petrol, diesel, hybrid).

Where to find a particular car's CO₂ emissions information?

You can find information about a car's CO₂ emissions from the following sources:

• The environmental label which should be displayed on all new cars in showrooms. This grades each car from A (the cleanest) to G (the most polluting).
• The Vehicle Certification Agency which has a database of cars with their fuel economy and CO₂ emissions data.
• In car adverts - manufacturers are obliged to publish CO₂ emission information by law.

What if I am purchasing a second hand vehicle?

The Society of Motor Manufacturers and Traders has a database of vehicle CO2 emissions going back to January 1997

Alternatively the VCA website has information on CO2 emissions from cars going back as far as 2000 in the downloads section so if you are buying a used car you may be able to find information on its fuel consumption and emissions there.