Eaton Roadranger

Eaton scientist co-authors SAE Book on Advanced Hybrid Technologies for Commercial Vehicles

Diversified industrial manufacturer Eaton Corporation's Chief Scientist, Dr. Haoran Hu, has co-authored a book entitled "Advanced Hybrid Powertrains for Commercial Vehicles." Published by SAE International, the 404-page book details the latest trends and technologies in the rapidly developing hybrid commercial vehicle market.

Hybrid powertrains, which have become widely available in passenger cars and light-duty trucks, are beginning to see more applications in the commercial truck industry too. The potential for significantly improved fuel economy, cleaner air, lower operating costs and less dependence on traditional fuel supplies are driving the market for hybrids, Dr. Hu noted. 

"Eaton already has achieved a 30 percent boost in fuel economy in tests with its electric-hybrid powertrain in the city bus driving cycle," Dr. Hu said. And, he added, recent tests by the U.S. Environmental Protection Agency demonstrated the potential for a 50 percent improvement with hydraulic hybrid systems.

The new SAE book covers the gamut of technologies intrinsic to developing hybrid commercial vehicles, including traditional internal combustion engines and advanced clutches and transmissions; energy storage systems (batteries, ultracapacitors and flywheels); and hydraulic-hybrid components and controls.

Next-generation technologies such as full-electric systems, fuel cells and the role hybrid commercial vehicles could play in future intelligent transportation systems also are detailed. Other chapters address government regulations and incentives as well as other market drivers and challenges.

Dr. Hu has a doctorate degree in mechanical engineering from Massachusetts Institute of Technology, and more than 20 years of experience in the research and development of internal combustion engines, advanced powertrain systems and emissions control technologies. He joined Eaton in 2002.

Dr. Hu co-authored the SAE book with Dr. Rudy Smaling, executive director of systems engineering at Cummins Engine Co. Inc., and Simon Baseley, who recently retired from Bosch Rexroth Corp. and is now a visiting research investigator at the University of Michigan.

The book can be ordered via SAE's Web site,

More than 6,000 of Eaton's hybrid systems are in use today worldwide on city and school buses, delivery trucks, refuse and recycling trucks and utility vehicles. These trucks have collectively logged some 300 million miles of safe and reliable service, which translates into estimated savings of more than eight million gallons of fuel.