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Wednesday, 3 October 2012

Buying a car: green tips

In the UK, most of the carbon dioxide (CO2) caused by individuals comes from driving cars. Find out how to reduce your environmental impact, why the size and model of your car matters, and how to choose a fuel efficient car.

Do you need a new car?

If you don't travel often or long distances you may not need to buy a car. Other types of transport could be just as convenient and could save you money. You could:

  • join a car club so you can hire a car when you need it
  • car share 
  • use public transport and taxis

Consider a second-hand car

If you need to buy a car, you could save money and the resources needed to make a new one by getting a second-hand model.

Some car dealers have fuel efficiency information on an easy-to-read label available for each second-hand car they are selling. You can also check how fuel efficient particular models are by using the used car search.

Think about fuel efficiency

Buying the most fuel efficient car in its class could save you up to three months’ worth of fuel per year

More efficient cars use less fuel, pay less car tax and emit lower emissions of carbon dioxide (CO2). Carbon dioxide is one of the main greenhouse gases responsible for climate change.

The tools below help you find out how fuel efficient vehicles are and the car tax payable on them.

The fuel economy label

Car showrooms display fuel economy labels to show how fuel efficient each new car is. The labels make it easy to compare different cars. They show:

  • a rating from band A (green) to band G (red), with A being the most fuel efficient
  • how much road tax is payable each year – the more fuel efficient the car is, the less tax you will pay

New cars: by make or model

If you have a particular make or model of car in mind, find out how fuel efficient it is and the car tax payable.

Used cars: find out fuel efficiency

Check how fuel efficient a used car is before you buy it. You will need to know the make and model of the car.

Consider model, make and size

The fuel economy of similar sized cars using the same type of fuel can vary by as much as 45 per cent. Even different versions of the same car model can be different, so check the fuel economy label.

As a general rule, smaller cars and cars with smaller engines are more fuel efficient.

Choose a high Euro number

All new cars have to meet 'Euro' standards. These set limits for emissions like particulates (soot) and NOx (nitrogen oxides) that can harm human health and the environment. Generally speaking, the higher the Euro number, the cleaner the car.

From 2011, all new cars will have to meet Euro 5 standards. This will reduce diesel cars’ particulate emissions to similar levels to petrol vehicles. From September 2015, new cars will have to meet Euro 6. This will reduce diesel cars’ NOx emissions, making them almost as clean as petrol cars in terms of pollutants. 

Some models will meet these standards before these dates. You can check the Euro standard of different cars on the car fuel database.

Petrol or diesel: know the differences

Knowing the difference between petrol and diesel can help you choose the right fuel for how you drive.


Petrol engines are less fuel efficient than diesel engines and generally produce more CO2.


Diesel engines give off more air pollutants like nitrogen oxides (NOx) and particulates (soot). These can lead to poor air quality, particularly in towns and cities, and be harmful to health.

Some new diesel cars come fitted with a DPF (diesel particulate filter), which reduces these pollutants. If you don’t have a DPF, ask your garage about getting one fitted.

Diesel cars meeting the Euro 5 and Euro 6 standards will produce fewer pollutants (the ‘Choose a high Euro number’ paragraph gives more details). If you are buying a diesel car, consider one that meets these more demanding standards.

Petrol or diesel?

If you drive more in town, where air quality is a consideration, a petrol engine may be a good choice. If you do a lot of long distance or motorway driving, consider a diesel engine for fuel efficiency and lower CO2 emissions.

Consider cars that use greener fuels

Greener fuels include electricity, biofuels and LPG. A Plug-In Car Grant is available to help with the cost of buying eligible cars that run on certain greener fuels.

For more information, see the links below.

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