Green Driving and the Environment

Posted on December 2nd, 2013 by GEM Motoring Assist

By paying careful attention to your choice of car, fuel and your style of driving, you will find it is possible to reduce the impact you have on the environment. Even if you do not believe the anti-car groups’ environmental arguments, you’re sure to agree that “driving green” makes good financial sense.


Choosing a car
When deciding to buy a replacement car, the choice can be quite bewildering. However, it’s best to weigh up the environmental cost with your own needs:
New cars tend to produce less harmful emissions, the recent introduction of the EC labelling system (similar to the type used for fridges and freezers) displays the fuel consumption and carbon dioxide (CO2) emissions for each new car model. The lower the rating, the lower your annual VED (car tax) or company car tax liability.

Away from the marketing gloss of the new car showrooms, remember that true environmental awareness takes into account the whole life cycle of the car, from manufacture to scrapping. It often makes good environmental sense to buy second-hand.

If replacing a car that had failed its MoT, it is often better for the environment to repair an older car than scrap it and buy another. Obviously, there comes a time when repairing a worn out car becomes economically unviable so ask the advice of a mechanic to see if your old vehicle will last another year or two with a modest outlay.

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Type of fuel
There are many different ‘alternative’ fuels currently available. These can help to reduce vehicle emissions. But not all of them have a positive impact on reducing carbon dioxide.

Biodiesel is a vegetable oil or animal fat-based diesel fuel which can be used at a 5% blend in existing diesel engines with no need for modification. It is different from the vegetable and waste oils used in converted diesel engines. Using higher than a 5% blend could affect your vehicle warranty.

Bioethanol is a form of renewable energy that can be produced from agricultural feedstocks. It is produced by the fermentation of starch, sugar and cellulose plants. A 5% blend in petrol can be used in existing petrol vehicles with no modifications.

Biogas is produced by the breakdown of organic matter where no oxygen is present.  In the process, organic materials are broken down by microbiological activity to produce methane. Biogas is believed to have the potential to replace around 17% of vehicle fuel.

Electricity is available to power vehicles either via pure electric or hybrid technology. Electric cars are usually powered by one electric motor or more, using electrical energy stored in batteries or another energy storage device.

Hybrid vehicles use two or more separate power sources. The term generally refers to hybrid electric vehicles (HEVs), which combine an internal combustion engine and one or more electric motors.

Liquefied petroleum gas (LPG) is a flammable mixture of hydrocarbon gases. It’s generally suitable for smaller vehicles such as cars and light vans that have high mileage or operate predominantly in city centres.

Experiments are on-going with hydrogen, but it is not yet available generally. It can be used as a fuel in a modified petrol engine or indirectly to power a fuel cell in an electric vehicle.

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Share and share alike
Consider car sharing for work or school runs or joining a car club which allows several people to share the cost, environmental impact and benefits of owning a car.

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During a journey
Before a long trip, ensure you have planned the route so time and fuel are  not wasted on getting lost. Tune your radio to receive traffic information so you can avoid congested areas. Make sure your vehicle is correctly maintained, the tyres are correctly inflated and you are not carrying any unnecessary items, which will increase your vehicle’s weight and therefore its fuel consumption.

Driving smoothly and anticipating the traffic conditions reduces fuel consumption and wear and tear. Also, turn off any extra accessories such as a heated rear windscreen or air conditioning. Do however, use the air conditioning for at least ten minutes every week to minimise the chance of its gas leaking into the atmosphere. Monitor your speed safely, as driving at 50 mph can use 25% less fuel than 70 mph.

Also question whether you should use the car for short journeys. These are worse for the environment as a car will use more fuel (modern cars still have a cold start “choke” system) and the catalytic converter, which removes the most harmful pollutants, will not be working efficiently.

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Q: Should I coast down a hill with the engine off to save fuel?
A: No. Switching off the engine means you lose the power assisted steering and brakes and engine braking, with obvious safety consequences. The most economical and environmentally friendly way is to select an appropriate gear and proceed with the clutch pedal released. On most modern cars, this activates a fuel cut-off, meaning that no fuel is being burnt inside the engine and therefore, no emissions.

Q: Which is better for the environment, petrol or diesel?
A: Diesel cars are more fuel efficient and produce less CO2, but they also produce particulates. Much depends on the make, model and age of vehicle. Ironically, as transport planners urge us to make better use of trains or buses, you’ll find that many of the latest diesel cars have particulate filters which the average train or bus may not!

Q: Should I switch off the engine when my car is stationary in traffic?
A: This depends on the situation. If you are not at a standstill for a long time, such as waiting for traffic lights to change, it isn’t really worth it as your engine has to be injected with extra fuel to get started again and it will need more once running to recharge its electrical system. For an extended period, such as a major traffic jam, it would be worth it.

Q: I have had my car converted to LPG. Will it be exempt from London’s congestion charging scheme?
A: Not necessarily as each alternative fuelled vehicle must meet strict emissions criteria, which are set by the Energy Savings Trust. These are on the PowerShift register ( which is an authoritative source of information regarding vehicles which are eligible for discount from the Transport for London congestion charge scheme.

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The information on this Site is provided on the understanding that GEM Motoring Assist is not rendering legal or other advice. You should consult your own professional advisers as to legal or other advice relevant to any action you wish to take in connection with this website.

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