12 March 2003

The Chicago, IL-based Engine Manufacturers Association (EMA) published a technical position statement on the use of biodiesel fuel in diesel engines. The statement provides an assessment of the potential effects of the biodiesel fuels use with current technology engines.

In the statement—while admitting that the information on biodiesel effects on engines that were not designed for that fuel is still limited—the EMA concluded:

  • Biodiesel fuels should meet the ASTM D6751 standard or an approved European specification (DIN 51606, EN 14214).
  • Fuels blending up to 5% biodiesel with petroleum-based diesel fuel (B5) should not cause engine or fuel system problems. The use of biodiesel blends above 5% should be consulted with the individual engine manufacturers.
  • Biodiesel blends may require additives to improve storage stability and allow use in a wide range of temperatures. The conditions of seals, hoses, gaskets, and wire coatings should be monitored regularly when biodiesel fuels are used.
  • Biodiesel fuels reduce emissions of hydrocarbons and carbon monoxide but increase nitrogen oxide emissions when compared to petroleum-based diesel fuel. Therefore, biodiesel or its blends should not be used as a means to improve air quality in ozone non-attainment areas.
  • Individual engine manufacturers will determine the implications, if any, of the use of biodiesel fuels on their commercial engine warranties.

The conclusion that biodiesel bends greater than B5 should not cause problems when used in existing diesel engines is consistent with the Common Position Statement issued in June 2000 by a consortium of fuel injection equipment (FIE) manufacturers. The FIE Manufacturers concluded that fuel injection systems can be designed for operation with neat biodiesel fuel (B100). However, in equipment designed for petroleum fuels, blends greater than B5 can cause reduced product service life and injection equipment failures.

Download: EMA Statement | FIE Manufacturers Common Position

Source: EMA