Cummins Inc. announced that its B4.5, B6.7 and L9 engine platforms are compatible with paraffinic renewable diesel fuels meeting the EN 15940 specification. Both on-highway and off-highway versions of the B6.7 and L9 platforms and all vintages are approved to use paraffinic diesel fuels in North America.

According to Cummins, this helps further reduce the carbon footprint of Cummins-powered bus, truck, agricultural and construction fleets operating around the world, as compared with conventional fossil-based diesel, paraffinic diesel fuels offer the potential to reduce greenhouse gas (GHG) emissions by 40% to 90% over the total life cycle of the vehicle.

Paraffinic diesel fuels can be used as a 100% substitute for standard EN 590 or ASTM D975 Ultra-Low Sulfur Diesel (ULSD) without requiring any change to the Cummins engine. No additional engine maintenance is required when using paraffinic fuels meeting the EN 15940 specification, and the same fuel filters are retained. Paraffinic diesel can be blended with standard diesel at varying percentages, including winter-grade fuels, and has the same stability and cold properties as conventional diesel, which means it can be used and stored in the same ways.

Cummins led an 18-month field trial running 100% paraffinic diesel fuel in order to understand changes in engine performance, aftertreatment effects and fuel system durability. Engine performance remained stable and consistent while using the paraffinic fuel, and Cummins says customers should not expect to see any differences. Depending on the application and the engine duty cycle, a fuel economy detriment of 0 to 6% is expected due to the lower density of paraffinic fuels compared with regular diesel fuel, according to Cummins.

A thorough analysis of the aftertreatment system showed that each subsystem—the Diesel Oxidation Catalyst (DOC), Diesel Particulate Filter (DPF) and Selective Catalytic Reduction (SCR)—remained stable throughout the test with performance similar to that of regular diesel fuel. The materials in the fuel system equipment (O-rings, injectors and pumps) are all compatible with EN 15940 diesel fuels.

Other light-duty, heavy-duty and high-horsepower platforms are currently undergoing a similar validation plan on 100% paraffinic fuels, and Cummins will be announcing the results of the studies throughout the year.