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The Environment

Green choices that are good for your pocket

Do your bit to help preserve the environment by choosing a car that uses less fuel and produces fewer toxic emissions.

Cars that use less fuel will be cheaper to run. Not only that, they go a long way to reducing the pollutants in the air. But there are other considerations if you want to help reduce emissions.

Size Matters

Buy the right car for your needs. People carriers make sense if you're going to use all the seats. But a smaller car is more economical if there's just the two of you.

Weight Matters

How much your car weighs is key to how much fuel it uses. In fact, weight is more important than engine size.

A heavy car uses a lot of fuel to get going and to stop. But if you have a big engine in a small car, this can be economical.

Manual or Automatic?

For a smooth drive around town, it's tempting to opt for an automatic or a car with continuously variable transmission (CVT). These cars are easier to drive as they have no clutch, and they change gear for you.

The flip side is that they use more fuel. Traditional Automatics may use around 10% more than manuals whilst cars with CVT use around 5% more.

There is however now a growing number of "automated manual" transmissions around. Essentially clever hydraulic and electronic systems take car of the clutch and gear change. These can offer a fuel consumption saving compared with 'normal' autos and manuals.

At motorway speeds fuel consumption evens out and there's not much difference between manuals and automatics. Modern semi-automatic features such as button-operated gear change and automatic clutch control help you use less fuel.

Four–Wheel Drive

Fuel consumption will be around 4% higher than for a two–wheel drive with the same style body. If you compare a four-wheel drive with the most economical vehicle that can carry the same load, the fuel consumption could be up to 14% higher for the four–wheel drive.

As with any class of car there are good and bad performers though – if you need a 4x4 then try to choose one of the more fuel efficient models.

Emissions

All cars give out carbon dioxide (CO2), the main gas behind climate change. The amount produced is directly related to fuel consumption.

All vehicles produce toxic emissions such as nitrogen oxide(NOx) too though there's less you can do to affect this other than trying to run the newest car you can.

New cars get tested to make sure their exhaust emissions meet European standards, which have been getting more stringent since the 1990s.

Since 1992, all new petrol cars have come with a catalytic converter. Catalytic converters came in as a result of the Euro I standard.

Each new standard is tougher than the last. We're now up to Euro IV which came into force in 2005 whilst the next, Euro V, will come into force in 2009.

The newer the car, the better for the environment. One pre-1992 car without a catalytic converter gives out roughly the same toxic emissions as 20 of today's new cars.

Fuel Choices

Petrol cars use more fuel than diesel, giving out around 10% more carbon dioxide (CO2). But petrol cars produce fewer toxic emissions than diesel.

Diesel cars use less fuel than petrol cars, so give out less CO2. Direct-injection diesel engines give the best fuel economy.

LPG gives off lower toxic emissions than Diesel and pre Euro IV petrol engines, but fuel consumption is worse.

Taxes and Charges

The price of Road Tax increases with the car's official CO2 emissions, so it pays to get a smaller, more economical car.

Even though they have lower CO2 emissions than petrol cars, diesels are more expensive to tax, because they produce more toxic emissions.

Company Car Tax is also based on the amount of CO2 your car emits. The less CO2 your car emits, the less tax you pay. There is a 3% surcharge for diesel cars because of their higher toxic emissions.

Some cars that use 'alternative' fuels get a 100% discount from the London Congestion Charge Scheme.

Going Green in a Nutshell

  • Opt for the smallest car that suits your needs
  • The less fuel you use, the less you pollute
  • Newer cars are generally better for the environment
  • Road tax is based on the fuel type, and the amount of CO2 your car emits
  • Manual cars generally use less fuel than automatics
  • LPG and diesel give out less CO2 than petrol cars
  • LPG and petrol cars give out less toxic emissions than diesels
  • Some alternative-fuel cars get a discount on the London Congestion Charge
  • The way you drive your car can affect the amount of fuel you use