EU: Fuels: Automotive Diesel Fuel

Environmental Regulations. Reductions in the sulfur content of diesel fuels were legislated with implementation deadlines from 2005 through 2011 [Directive 2003/17/EC][Directive 2009/30/EC]. These requirements are reflected in the 2004 and 2009 editions of the EN 590 standard, Table 6.

The following sulfur limits were adopted for diesel fuels used in road vehicles:

• A maximum sulfur limit of 50 ppm was introduced effective 1 January 2005, coincidentally with Euro 4 emission regulations.
• Also from 1 January 2005, 10 ppm S fuel (both diesel and gasoline)—sometimes referred to as “sulfur-free” fuel—had to be available “on an appropriately balanced geographical basis”.
• A maximum sulfur limit of 10 ppm became effective on 1 January 2009.

EN 590:2004 fuel with the 50 ppm sulfur limit is sometimes referred to as ‘Euro 4 diesel’, and that with 10 ppm sulfur limit as ‘Euro 5 diesel’. Note that these designations are customary—they are neither a part of the emission directive nor the EN 590 specification.

Sulfur limits in diesel fuels for mobile nonroad vehicles, including mobile machinery, ag and forestry tractors, as well as inland waterway vessels and recreational craft, are:

• 1000 ppm, effective 1 January 2008, and
• 10 mg/kg effective 1 January 2011.

The following flexibilities applied to the nonroad fuel requirements: (1) In order to accommodate contamination in the supply chain, Member States could, from 1 January 2011, permit nonroad fuels to contain up to 20 mg/kg of sulfur at the point of final distribution to end users; (2) Member States could permit the continued placing on the market until 31 December 2011 of fuels containing up to 1000 mg/kg sulfur for rail vehicles and ag and forestry tractors, provided that they ensured that the proper functioning of emissions control systems will not be compromised.

Biofuel Content. Fuel suppliers were required to reduce life cycle greenhouse gas emissions by up to 10% per unit of energy—relative to the EU average 2010 levels—by 31 December 2020 [Directive 2009/30/EC]. This reduction should have amounted to at least 6% obtained through the use of biofuels, alternative fuels and reductions in flaring and venting at production sites. The Directive defined sustainability criteria for biofuels used to fulfill the obligation. Subject to a regulatory review, a further 2% GHG emission reduction was to be obtained through the use of carbon capture and storage technologies and electric vehicles, and an additional further 2% reduction through the purchase of credits under the Clean Development Mechanism of the Kyoto Protocol.

The content of fatty acid methyl ester (FAME) biodiesel was limited by EN 590:2009 at 7%, up from 5% in the 2004 revision of the standards. While these limits have been adopted for technical reason, Directive 2009/30/EC allowed Member States to place on the market biodiesel of FAME content greater than 7%. Future revisions of EN 590 are expected to allow FAME content up to 10%. The maximum content of non-FAME biofuel components, such as diesel-like hydrocarbons made from biomass using the Fischer-Tropsch process or from co-processed or hydrotreated vegetable oil (HVO) is not limited.

Other EN 590 Changes. In addition to the new sulfur, aromatics and FAME specifications, EN 590:2009 introduced several other changes, including:

• Additional requirement and method (EN 15751) to determine the oxidation stability, with a limit of 20 h.
• Ignition Quality Tester as an alternate test method to the CFR engine test.
• Revised total contamination test method EN 12662 to improve precision for FAME containing product.
• Revised EN 12916 method to distinguish between polycyclic aromatic hydrocarbons and FAME.

Effective 1 January 2000, a maximum sulfur limit of 350 ppm and cetane number of 51 was introduced for diesel fuel for road vehicles [Directive 98/70/EC]. The changed diesel specifications are covered by the updated EN 590:1999, Table 7. These changes were introduced coincidentally with the Euro 3 emission regulation, and the fuel is sometimes referred to as the Euro 3 diesel.

The EN 590:1999 CFPP point specification (Temperate Climate Grades of diesel fuel) remained unchanged (see Table 11).

Specifications for Arctic Classes of diesel fuel according to EN 590:1999 are shown in the following table. Note that the cetane number values of the Arctic Classes do not meet the requirements of EU Directive 98/70/EC; the Arctic Classes specifications can be used in countries where the Directive does not apply, or in areas that have been granted exceptions.

Climate grades of diesel fuels adopted by European countries are listed in Table 9.

The EN 590:1993 included a sulfur limit of 0.2% (wt.), which became effective from October 1994 [Directive 93/12/EEC]. This sulfur limit was applicable to all gas oils, including diesel fuel. Details on the EN 590:1993 specification are listed in Table 10.

To account for different climate conditions, the EN 590:1993 standard defines six Temperate Climate Grades and five Arctic Grades of diesel fuel, as shown in Table 11 and Table 12. Each Member State should detail requirements for a summer and winter grade as well as intermediate or regional grades, if needed.