On Jan. 6, 2002, Ford Motor Company unveiled en innovative powertrain enhancement on the Mighty F-350 TONKA concept truck.
The Hydraulic Power Assist (HPA) system uses existing hydraulic technology in a novel way to improve fuel economy in large trucks in city driving by an estimated 25 to 35 percent.
Like a wind-up toy, the system recovers kinetic energy normally lost during deceleration, stores it as hydraulic pressure, and then reuses it during acceleration.
Early next year Ford will launch a pilot fleet of E-550 commercial vans for production prove-out of the system. It is best suited to large trucks in an urban stop-and-go duty cycle, such as delivery vehicles. Initial research indicates that HPA will reduce vehicle emissions by 20 percent. Brake wear would also be cut by up to 70 percent, lowering operating costs for commercial fleets.
The system, which recovers up to 80 percent of the initial kinetic energy during deceleration, was developed by Ford, Eaton Corp. and the U.S. Environmental Protection Agency in a hydraulic hybrid research project.
Early research indicates that application of HPA could be ideal for larger vehicles such as commercial trucks, delivery vans, buses and work trucks. Heavier vehicles employ more energy in stop-and-go traffic, creating greater opportunities to capture and reuse that energy.