U.S. Environmental Protection Agency (EPA) standards require a major reduction in the sulfur content of diesel fuels and emission levels from diesel engines and vehicles. To meet the EPA standards, the petroleum industry is producing Ultra Low Sulfur Diesel (ULSD) fuel, a cleaner-burning diesel fuel containing a maximum 15 parts-per-million (ppm) sulfur.
Effective June 1, 2006, 80 percent of the highway diesel fuel produced or imported is required to be ULSD fuel replacing most Low Sulfur Diesel (LSD) fuel, which contains a maximum of 500 ppm sulfur. Used in combination with cleaner-burning diesel engines and vehicles, ULSD fuel helps to improve air quality by significantly reducing emissions. By December 1, 2010, all highway diesel fuel offered for sale must be ULSD fuel.
Energy Tomorrow Radio Podcast on ULSD
Between now and 2010, both ULSD fuel and Low Sulfur Diesel fuel are allowed to be sold for highway use. Some retail outlets will sell ULSD fuel, others Low Sulfur Diesel fuel, and some will sell both.
ULSD fuel will burn cleaner in both existing diesel engines and in the new highway diesel engines and vehicles that will be equipped with advanced emissions control systems beginning with the 2007 model year.
The EPA requirements for highway diesel fuel were predominantly implemented in 2006.
EPA fuel standards for locomotive, marine and non-road diesel fuel engines and equipment, such as farm and construction equipment, become effective at dates later than those for highway vehicles (except in California).
Many public and private organizations are collaborating through the Clean Diesel Fuel Alliance to facilitate the transition to ULSD fuel. The U.S. Department of Energy (DOE), the U.S. Environmental Protection Agency (EPA), engine, vehicle and component manufacturers, all sectors of the petroleum industry, and fuel consumers, such as truckers, are providing comprehensive information and technical coordination. Click here for a complete list of participating organizations regarding ULSD fuel.