The People of America's Oil and Natural Gas Indusry

Clean Diesel in Your Tank

Jane Van Ryan

Jane Van Ryan
Posted January 5, 2010

The most massive fuel transition ever attempted in the United States has been occurring quite smoothly over the past few years without so much as a hiccup. It is the slow and steady movement from Low Sulfur Diesel Fuel to Ultra Low Sulfur Diesel (ULSD) fuel that started in 2006 and will continue through 2014.

ULSD fuel was mandated by the Environmental Protection Agency (EPA) to pave the way for the introduction of new diesel engines and vehicles starting with the 2007 model year. Working together, the new cleaner-burning fuel and the new engines and vehicles are helping to improve air quality by significantly reducing emissions.

The EPA says annual emission reductions will be equivalent to removing the pollution from more than 90 percent of today's trucks and buses, when the current heavy-duty vehicle fleet has been completely replaced in 2030. Additionally, the EPA says ULSD fuel enables diesel-powered passenger cars and light trucks to meet the same stringent emissions standards as gasoline-powered vehicles.

The transition to ULSD fuel, which contains a maximum 15-parts-per-million sulfur, began June 1, 2006, when refiners and importers nationwide were required to ensure that at least 80 percent of the volume of the highway diesel fuel they produced or imported was ULSD-compliant. Starting on December 1, 2010, only ULSD fuel will be available for highway use nationwide. (California was an early adopter of ULSD fuel, and it has been the only diesel fuel offered for sale in that state since September 1, 2006).

ULSD fuel standards become effective for non-road diesel equipment later than those for highway vehicles. By June 2010, the ULSD fuel standard of 15 ppm sulfur will apply to non-road diesel fuel production. Beginning in 2012, locomotive and marine diesel fuel must be ULSD-compliant with a few exceptions. (In California, locomotive and marine diesel fuel transitioned to 15 ppm sulfur on January 1, 2007).

EPA conducts regular surveys to ensure that diesel fuel pumps are properly labeled, indicating the type of diesel fuel being offered for sale. These surveys show that about 98 percent of diesel pumps are dispensing ULSD fuel nationwide.

A public-private coalition called the Clean Diesel Fuel Alliance has been following the transition closely and works to explain the ongoing transition to ULSD fuel. Anyone with questions about ULSD fuel can read a list of Frequently Asked Questions and listen to the Energy Tomorrow Radio episode on ULSD fuel below.