312.644.6610, ext. 3393




CHICAGO (Nov.1, 1999) -- The Engine Manufacturers Association (EMA) sponsored an economic study on the refining costs associated with the desulfurization of diesel fuel. The study concludes that the incremental cost to reduce current sulfur levels in diesel fuel 90% from 500 ppm to below 50 ppm would be on average about 5-7 cents per gallon.

The report, entitled "Refining Economics of Diesel Fuel Sulfur Standards" was prepared by MathPro, Inc. and was developed with the cooperation of the American Petroleum Institute (API), the National Petroleum Refiners Association (NPRA) and various refinery technology vendors. The MathPro final report can be downloaded in PDF format. More interesting is that the study also found that it would cost only an additional 2 cents per gallon to go the rest of the way from 50 ppm to below 5 ppm sulfur", said Glenn Keller, EMAs Executive Director. "Sulfur in motor vehicle fuels is known to inhibit the performance of certain emission control devices to be used on diesel engines."

A 5 ppm sulfur cap also is what emission control device manufacturers have identified as necessary to maximize the performance of their control technologies.

The US Environmental Protection Agency and the California Air Resources Board have announced that the next generation of diesel engines will be required to achieve more than a 90% reduction in NOx and particulate emissions from 2004 product. "This emissions reduction target will require near zero levels of sulfur to enable the commercial viability of catalytic controls being developed for diesel engines," replied Keller.

"Engine manufacturers have already reduced diesel engine particulates by 90% and NOx by 70% since the mid-70s," said Keller. "This industry is committed to further emissions reductions and is working with fuel producers and catalyst suppliers to develop the next generation of emission control technologies."


EMA is a trade association representing worldwide manufacturers of internal combustion engines for all application except passenger cars and aircraft. The EMA continues to work with government and industry stakeholders to help the nation achieve its goals of cleaner fuels, more efficient engines and cleaner air. For more information contact Anne Rukavina at (312) 644-6610 x3393 or visit our website at

-Engine Manufactures Association