How to… drive efficiently

When it comes to driving emissions, most of the recent controversy has surrounded a certain kind of automobile – yes ‘sport’ utility vehicles, I’m looking at you.

But it is not just the type of car that determines its emission levels; mankind can make many moves that will reduce the CO2 spew when getting behind the wheel.

According to government statistics, CO2 emissions from private cars have increased by four per cent since 1996, despite a six per cent improvement in the fuel efficiency of newly manufactured cars. No matter how cars are produced, the decisions and driving styles of drivers are continuing to influence the overall emissions from cars, but this is rarely understood by drivers who often believe their car will deliver a set number of miles to the gallon regardless of their activities.

But driving behaviour, journey planning and car preparation have a direct impact on an individual's fuel efficiency. Whether the trigger to change driving styles comes from the inclination to reduce your environmental impact, to save money or perhaps to comply with your employer's demands for more environmentally responsible driving, you need to grasp the idea that your car does not automatically do 20 miles to the gallon – you have to drive your car at 20 miles to the gallon.

Here is how you do it:

First and foremost, minimise your vehicle use

Vehicles are least fuel efficient and most polluting at the start of journeys and on short trips. One reason for this is that catalytic converters (which reduce air pollution emissions) do not operate properly until they have warmed up. Trips of less than 5km generally do not allow the engine to reach its peak operating temperature. By planning to complete a number of tasks in one trip you save both time and fuel. You should also try to avoid short vehicle trips altogether by walking or cycling.

Less stopping and starting means less CO2

Every time you stop then start again in a traffic queue, the engine uses more fuel and therefore produces more CO2. Keep an eye on the traffic ahead, anticipate and slow down early by gently lifting your foot off the accelerator while keeping the car in gear.

Over revving accelerates emissions

Modern car engines are designed to be efficient from the moment they are switched on, so revving up like a Formula 1 car in pole position only wastes fuel and increases engine wear. Using your gears wisely by changing up a gear a little earlier also reduces revs and emissions.

Control your speed

Staying at or within the speed limit increases driver safety, reduces CO2 emissions and saves on your petrol costs. At 70mph you could be using up to nine per cent more fuel than at 60mph and up to 15 per cent more fuel than at 50mph.

Careful motorway driving

Careful motorway driving will improve safety and traffic flow. When you see a car brake up ahead, simply take your foot off the accelerator. By the time you get close to the car in front the chances are that they will have speeded up.

Use air conditioning sparingly

Air conditioners can add on about 10 per cent to fuel consumption when operating. However, at speeds of over 80km/h, use of air conditioning is better for fuel consumption than an open window as this creates aerodynamic drag. If it is hotter inside your car than outside when you start a trip, drive with the windows down for a few minutes to help cool the car before starting the air conditioning.

Pump up to cut down

Under-inflated tyres create more resistance when your car is moving, which means your engine has to work harder, so more fuel is used and more CO2 emissions are produced. Simply check and adjust your tyre pressures regularly and before long journeys. This will also help to increase the life of your tyres and improve efficiency.

Less clutter in your car means less CO2

Avoid keeping unnecessary items in your vehicle, especially heavy ones. An extra 100 pounds in your vehicle could reduce your MPG by up to two per cent. The reduction is based on the percentage of extra weight relative to the vehicle's weight and affects smaller vehicles more than larger ones.

Replace dirty air intake filters

Replacing a clogged air filter can improve your car's fuel mileage by as much as 10 per cent. Your car's air filter keeps impurities from damaging the inside of your engine. Not only will replacing a dirty air filter save fuel, it will protect your engine.

Ensure your engine is properly tuned

Fixing a car that is noticeably out of tune or has failed an emissions test can improve its fuel mileage by an average of four per cent, though results vary based on the kind of repair and how well it is done. Fixing a serious maintenance problem, such as a faulty oxygen sensor, can improve your mileage by as much as 40 per cent.

Minimise aerodynamic drag

Additional parts on the exterior of a vehicle such as roof racks and spoilers increase air resistance and fuel consumption, in some cases by more than 20 per cent at higher speeds. Remove roof and bike racks when not in use.

Follow these simple steps and you will find it is possible to slash carbon emissions and fuel bills while also prolonging the life of your vehicle. In the short term at least, it is as much these behaviour changes as changes in technology that will deliver significant improvements in road transport emissions.

Amy Sims is communications manager at Global Action Plan.

To help improve driving styles Global Action Plan provides a bespoke driving simulator that helps people drive in an environmentally friendly way while competing against one another.

The aim is to help users quickly learn how to be more fuel efficient, through anticipating better and making simple changes to their vehicles and driving styles.