Fuels traditionally were complex mixtures of hydrocarbons derived from crude oil and separated by their boiling range. However today, in order to help tackle climate change and air pollution, these traditional fuels can contain increasing amounts of renewable biofuels – fuels derived from material obtained from plants and animals. In addition to the climate change benefits these often locally produced biofuels offer a degree of energy security and are less sensitive to supply disruption and the associated price variation.
The different types of fuels and their application are summarised below:
Petrol conforms to BS EN 228. Two grades:
- BS EN 228( E5 ) grade containing up to 5% ethanol
- BS EN 228 (E10) containing up to 10% ethanol
Ethanol is a renewable fuel derived from crops such as sugar cane/beat and maize/corn.
Ethanol used for blending with traditional fuel for petrol engine vehicles must conform to the standard BS EN 15376. This standard specifies the requirements and test methods for the ethanol be to used for blending.
Regular petrol is sold with a minimum research octane number ( RON ) of 95. Premium grade petrols are sold on the market with higher RON values. These fuels fully comply with the specifications set out in the BS EN 228 standard and there is no longer a separate standard for these higher RON grades.
A new grade of petrol comprising 85% ethanol is being developed to run on ethanol E85 fuel. This standard is prEN 15293, This standard is likely to be agreed and published in 2018.
Regular diesel fuel conforms to the requirements set out in BS EN 590.
This standard allows for the provision of a seasonal variation to ensure safe operation during the winter months. The standard also allows for the fuel to contain up to 7% of biodiesel, as fatty acid methyl ester ( referred to as B7 ). The fatty acid methyl ester material is a renewable diesel fuel derived from animal fats and vegetable oils. This material must conform to the requirements set out in the standard BS EN 14214.
Other diesel fuels have been developed with increasing amounts of fatty acid methyl ester content for use in captive fleet applications. These include BS EN 16734 for diesel fuel containing up to 10% fatty acid methyl ester, referred to as B10, and BS EN 16709 which outlines two different grades of diesel fuel, one containing 14 – 20% biodiesel (B20) and the other containing 24 – 30% biodiesel (B30). Again the fatty acid methyl ester blend component must comply with the requirements set out in BS EN 14214.
A new type of diesel fuel has been developed made synthetically from non- crude oil derived materials. BS EN 15940 sets out the requirements and test methods for paraffinic diesel fuel originating from synthesised gas or hydro-treatment of bio-oils and fats. Two classes are defined within the standard, one class showing improved ignition quality compared to regular diesel fuel. The standard allows for the blending of up to 7% biodiesel as fatty acid methyl acid, providing this material conforms to the requirements set out in BS EN 14214. Paraffinic diesel fuel may be used directly in vehicles designed for its use, or it may be blended with automotive diesel fuel.