The UK car market has changed over the last 40 years, and this could be having a big impact on the environment as cars are a huge factor in the UK’s CO₂ emissions. One million extra cars are bought every year now compared to that in the 1970 and the Energy Saving Trust estimates that there are more than 29 million cars on the road, so one car for every two people [1]. More than a quarter of the UK’s total CO₂ emissions is from road transport and 55 percent of this is from passenger cars. Consequently, buying more efficient cars has the potential to make a significant reduction to the national CO₂ emissions. Not only that, it can save you money as a more efficient car is a cheaper car.

Buying a new car

If you can afford to splash out on a new car the you’re in a good position to make a difference. Cars today are generally more fuel efficient than pre-2000 model – at least 20 percent, so you can cut both your fuel consumption and your CO₂ emissions. Here are some things to think about:

• What type of car do you need? If you have a small family, it’s unlikely that you will need a people carrier. Aim to choose the car with lowest emissions that meets your needs – you could save the equivalent of four months fuel each year [2].
• Check the emissions. New cars in showrooms have labels in the windscreen with full details about fuel economy and carbon emissions, and a grading from A (the cleanest) to M (The most polluting). Adverts for new cars in newspapers and on TV must publish information about fuel economy and CO₂ emissions. The Vehicle Certification Agency also provides information on new car fuel consumption and exhaust emissions [2].
• Consider diesel. Although diesel costs more at the fuel pump and diesel cars are in general more expensive, they often have lower CO₂ emissions than the petrol equivalent. If you have a high mileage you are more likely to be rewarded for using diesel, whereas if you only have a low mileage the overall cost of ownership will be less on a petrol car.
• What about a hybrid? These have both a conventional engine and an electrical motor powered by batteries which recharge as you drive. Some models can travel more than 70 miles on a gallon of fuel, however they tend to be more efficient in urban driving so if you drive a lot on motorways they may not be the best choice for you.

Buying a used car

If you’re buying a used car, it is useful to consider all of the things above. Furthermore, have a look out for:

• An efficient engine – engines should be smooth an even. A rattly engine will not be as efficient.
• Good quality tyres – Uneven or worn tread on a tyre effects fuel consumption.
• Smooth oil – sludgy oil means the engine is damaged in some way.
• Clean exhaust fumes – black smoke = pollution.
• A diesel particulate filter – to prevent dangerous pollutants into the atmosphere.
• Genuine MOT certificates – make sure that a car’s emissions are in line with their expected levels in the Vehicle Certification Agency database.
• A full service history – a regularly serviced car is more likely to be efficient [3].

If in doubt, remember the basics

Make sure you remember the CO₂ emissions basics:

• A more efficient car generally has lower CO₂ emissions.
• Smaller cars with smaller engines generally produce less CO₂.
• Road tax is lower for cars with lower CO₂ emissions. You pay no road tax on cars that emit up to and including 100g of CO₂ per km[2].
• Don’t just buy an efficient car – drive smartly as well.

[1] http://www.energysavingtrust.org.uk/Travel/Buying-a-car/Why-buying-green-matters

[2] http://www.energysavingtrust.org.uk/Travel/Buying-a-car/Buying-a-new-car

[3] http://www.energysavingtrust.org.uk/Travel/Buying-a-car/Buying-a-used-car