Cummins announced that its B4.5, B6.7, and L9 engine platforms are compatible with certain kinds of renewable diesel fuels.

Both on-highway and off-highway versions of the engines and all vintages are approved to use paraffinic renewable diesel fuels meeting the EN 15940 specification. Compared to conventional diesel fuels, paraffinic diesel fuels can potentially reduce greenhouse gas emissions by 40% to 90% over the total life of the vehicles, according to Cummins.

Cummins held an 18-month field test of its engines running 100% paraffinic diesel fuels in order to study the effects of the fuel on engine performance, aftertreatment and fuel system durability. Engine performance remained stable and consistent while using the paraffinic fuel, Cummins found. Depending on the application and engine duty cycle, fuel economy could take a hit of up to 6%, mostly due to the lower density of paraffinic fuels compared to regular diesel.

Cummins approval for the use of renewable diesel with B6.7 and L9 engines aligns with the introduction of EN 15940, a final European CEN specification for paraffinic diesel fuels. Paraffinic fuels include hydrotreated vegetable oil, gas-to-liquids, and biomass-to-liquids. Operators of Cummins-powered trucks and buses are required to source all paraffinic fuels from high-purity suppliers meeting EN 15940, as this ensures that the fuel contains the necessary lubricity additive for use in a diesel engine.

The company is currently putting other light-duty, heavy-duty and high-horsepower engine platforms through similar field tests; Cummins will announce the results of the studies later in the year.

"Focused on energy diversity and enabling the power of choice, Cummins has provided another approved fuel option to help the continued reduction of emissions," said Jim Fier, Cummins vice president, engineering. “The use of paraffinic diesel allows customers to minimize their emissions-based footprints without additional capital investment. Plus, they have the comfort of knowing that Cummins conducted a thorough analysis prior to approval.”