Reducing Exhaust Emissions

In the UK, road transport is responsible for around 20% of the CO2 (carbon dioxide) that we release. There are many ways to improve 002 emissions apart from economising on fuel and choosing more fuel efficient vehicles. Technical advances have already been made in the reduction of toxic exhaust emissions. Over the last 25 years the introduction of unleaded fuel, catalytic convertors and improvements in fuel economy have helped enormously.

Since 1993, European regulations have imposed strict emissions standards on all new cars. These requirements were tightened in 1996 and will be further tightened in the years 2000 and 2005. These are the latest in a whole line of EU directives that have resulted in the elimination of the most harmful emissions, currently around 90% of hydrocarbons, carbon monoxide, nitrogen oxides and low-level ozone from new petrol engine cars and vans.

However, if no further measures are taken, it is estimated that, after 2010, emissions will once again begin to increase as the predicted growth in traffic offsets the reductions brought about by improved technology. Most government action plans include a requirement to have a percentage of certain types of vehicles, such as city centre buses and taxis, operating on alternative fuels within an agreed time span.

As can be seen above, much has been accomplished in recent years, by improving exhaust emissions of vehicles, but even so, catalysts and unleaded petrol are only small steps towards cleaner engines. Much can be accomplished by using alternative fuels.

There are various alternative fuels that can be used and all have advantages and disadvantages when compared with the petrol and diesel that we are all used to. Many sing the praises of electric vehicles, especially for use in city centres. The electric car itself, gives zero emissions, but when you take into account that the electricity has to be generated at a power station, then transferred to the electric vehicle by charging the batteries, the overall emissions are not so favourable. Although at least the emissions are produced away from city centres.

The use of Hydrogen has been talked about and tested for many years. It has been called the fuel of the future. Due to the storage and refuelling problems, perhaps it always will be the fuel of the future! Well at least until such time that water (H20) can be split into Hydrogen and Oxygen cheaply and efficiently.

In August 1996 our Government officially admitted that people are being killed off by air pollution from traffic, and particularly from diesel engine vehicles. This was stated in their air quality targets. John Gummer, the Environment Secretary at the time, announced maximum concentrations for eight known pollutants which cause cancer or restrict lung function. Back In November 1995 Mr Gummer was told by his expert panel on air quality standards that up to 25 people a day were dying as a result of minute particles in air, mostly from vehicle exhausts and the majority from diesel engines.

Since then, in November 1997, the Government Car Service has stated that it will be converting or changing its fleet of 160 cars to alternative fuels over the next three years. In looking for low emission vehicles, we do not necessarily have to wait until the next millennium.

Natural gas, as the cleanest fossil fuel, represents an attractive alternative to petrol and diesel. Thanks to the absence of impurities and residual combustion products. Natural gas has become accepted in many parts of the world as the third most popular vehicle fuel, although on a global basis natural gas accounts for only 0.2% of the vehicle fuel used. The leader of the alternative fuels market is Autogas with 0.9% share and its popularity is growing all the time.

[What is autogas?]