Hydraulic Hybrid Truck Drive Launched: Improves Economy, Power

Permo-Drive Technologies has developed a compact version of a hybrid hydraulic drive system that promises to improve the fuel-economy of medium-duty commercial vehicles by 30 percent or more. Speaking at the third annual Clean Heavy-Duty Vehicles Conference on Feb. 19-20 in Tempe Arizona, Paul Chandler, vice president of North American Operations for Permo-Drive said that the new system is “ideally suited for Class VI-VII trucks and represents an important, evolutionary step in the development of hybrid hydraulic drive technology.” The second-generation system weighs approximately 330 pounds, and when fully charged can generate power equivalent to a 340-horsepower engine with 995 foot-pounds of torque. Production is planned for 2005. Permo-Drive’s system captures normally wasted energy generated during braking, then releases it back into the vehicle’s driveline when additional power is needed.

“Installed on a medium-duty truck, the system acts like a second 340-horsepower engine,” Chandler noted. “It dramatically reduces the need for fuel, while providing additional horsepower when necessary.”

The Permo-Drive RDS storage system includes two hydraulic fluid “accumulators” — a high-pressure tank (up to 5,000 PSI) and a low-pressure reservoir. As braking takes place, energy is captured with the flow of oil from the low-pressure tank to the high-pressure accumulator. A central processor later controls the release of the oil during acceleration to enhance overall fuel economy and reduce emissions. Permo-Drive Technologies Ltd. is an Australia-based company focused on the development of regenerative energy-management systems for the automotive industry.