ACEA

Fuel quality is extremely important

Fuel quality is very important and manufacturers treat the engine-fuel-exhaust after-treatment package as a complete and optimised system. Market petrol and diesel are complex products containing many different elements, compounds and characteristics. These may result from the basic crude oil, they may be a characteristic of the refining process or they may be added to enhance the performance of the final product.

Auto-makers simply demand that market fuels are ‘fit for purpose’. This means they provide the desired performance, they help reduce emissions (tailpipe gaseous and particle emissions and evaporative emission from the fuelling system), they help to keep engines running cleanly, they are not apt to degrade in performance or quality, they are available at all filling stations across the EU (and further afield) and meet a common standard and the fuels are properly labelled at the pump.

Emission limits

Over the years, legislation in the EU has introduced tighter emission limits and, in parallel, there have been improvements in market fuel quality. In the early 1990’s, the European automotive and oil industries co-operated in a program known as the “Auto-Oil program” to develop relationships between emissions performance and fuel quality. This program led directly to the EU legislation applying the Euro 3 & 4 emission standards in Directive 98/69/EC and, in parallel, requisite fuel quality standards in Directive 98/70/EC.

EU legislation therefore clearly recognises the link between engine emissions and overall performance with fuel quality. For example, the following table shows the parallel introduction of the UN-ECE Regulation No.83 light-duty vehicle emission standards (equivalent to EC Directives) with fuel quality standards:

In the EU, the relevant standard for market petrol is EN228 and the relevant standard for market diesel is EN590. These standards are, in the main, applied in national laws across the EU and drivers ‘should’ see these markings on the pump at filling stations. In addition, EU Directive 98/70/EC (as amended) makes it mandatory for Member States to apply legislation in their territory to limit and control a number of specific characteristics of petrol and diesel that are important on health or environmental grounds.

The following tables show the list of important characteristics for petrol and diesel and also show how certain characteristics have improved with the introduction of tighter emission standards (see table above). The characteristics controlled by Directive 98/70/EC on health and environmental grounds are shown in bold:

Of course, there are obligations to control the quality of fuel being sold at the filling station pump. Refiners will conduct their own quality auditing procedures and Directive 98/70/EC requires that Member States must monitor and report on the compliance of market petrol and diesel with the standards by testing samples of the fuels according to the various test methods laid down in EN228 and EN590.

• Directive 98/70/EC on Fuel Quality
• European Commission: Promoting biofuels as credible alternatives to oil in transport
• European Commission: Stricter fuel standards to combat climate change and reduce air pollution

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