Eaton, EPA say hydraulic hybrid truck showing big fuel economy gains

CLEVELAND, Ohio — Eaton Corp. and the U.S. Environmental Protection Agency (EPA) have showcased the first-ever hydraulic hybrid diesel urban delivery vehicle currently running real miles with UPS’ fleet.

Tests show the patented hydraulic hybrid diesel technology is achieving a 60 to 70 percent improvement in fuel economy and more than a 40 percent reduction in carbon dioxide emissions.

In the series hydraulic hybrid truck, a high-efficiency diesel engine is combined with a unique hydraulic propulsion system to replace the conventional drivetrain and transmission. The vehicle uses hydraulic pump motors and hydraulic storage tanks to recover and store energy, similar to what is done with electric motors and batteries in hybrid electric vehicles. Vehicle fuel economy is increased in three ways: braking energy that normally is wasted is recovered and reused; the engine is operated more efficiently; and the engine can be shut off when not needed, such as when stopped or decelerating.

EPA estimates that the technology has the potential to save more than 1,000 gallons per year for each urban delivery vehicle. UPS will begin testing the vehicle this year on the road in the Detroit area and then will bring it to Cleveland for additional testing. The vehicle was developed through a partnership between EPA, Eaton, UPS, International Truck and Engine Corp. and the U.S. Army.

“Eaton is proud to be working with the EPA and our industry partners in bringing this leading- edge technology to market,” said Alexander M. Cutler, Eaton chairman and chief executive officer. “Innovative technologies such as the hydraulic hybrid truck represent Eaton’s focus on energy management, market-leading products and environmental responsiveness.”