EPA announced the road test of a United Parcel Service hybrid delivery vehicle, which was developed in partnership with International Truck & Engine Corp., Eaton Corp. and the U.S. Army. According to EPA, lab tests of the technology demonstrated a 60-70% improvement in fuel economy and a 40% reduction in greenhouse gases. EPA and UPS plan to evaluate the vehicle's fuel economy performance and emissions during a series of tests this year.
In a joint press release, Eaton, International and UPS said that this is the first “series” hydraulic hybrid delivery vehicle, which means the engine is not connected to the wheels, but rather powers the hydraulic system, which in turn spins the wheels. “If parallel hybrids are an evolutionary step, series are a revolutionary step,” Brad Bohlmann, business development coordinator at Eaton Corp.'s Fluid Power Group, told Fleet Owner.
“The operational savings this vehicle could yield is based on three aspects,” Bohlmann said. “First is the fuel savings — because the series hydraulic system acts as a continuously variable transmission,” Bohlmann said, explaining that the diesel engine runs separately from the vehicle speed. “That allows you to run the engine at a speed load point that is at or near the optimal setting. Second is its regenerative nature. With this system we could save 70% of the vehicle's kinetic energy when decelerating and use it for acceleration. It's free energy. And last, brake maintenance is reduced substantially. The brake life is quadrupled, according to EPA estimates.”
EPA estimates that the added upfront cost for the hydraulic components could be recouped in less than three years. Given today's fuel prices, the vehicle could net a savings that could exceed $50,000 over the span of its lifetime EPA said. Eaton and the U.S. Army developed the hydraulic technology; the chassis was provided by International Truck & Engine Corp.