Ultra-low Sulfur Diesel [ULSD]

ULSD is simply conventional diesel fuel with a lower sulfur content than diesel. The EPA currently requires that most of the diesel fuel in the US—whether produced there or imported—is ULSD. The EPA does not consider ULSD an alternative fuel if that diesel is oil-based, but it does if the diesel comes from renewable sources.

snow truck ulsd

CO2 Emissions

ULSD does not reduce carbon dioxide emissions. It does, however, reduce others (see Advantages below)

Fuel Blends

ULSD can be blended with biodiesel


The current infrastructure is already being used for ULSD.


ULSD allows manufacturers to apply to diesel vehicles technologies to control the emission of nitrogen oxides (NOx) and particulate matter (PM) that the presence of too much sulfur would not otherwise permit. Together, ULSD and the technologies are called Clean Diesel.


ULSD offers no discernable difference in fuel economy or performance versus diesel.

Lower sulfur content creates some corrosion problems because the fuel’s lubricity (XXXX) has been reduced. Additives, as well as a ULSD/Biodiesel blend can overcome this.

ULSD may cause mechanical problems in older diesel vehicles.

The Future…

Across the world, ULSD is a rapidly expanding industry and is considered one of the most promising emerging fuels at the moment.

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