International Truck and Engine and Eaton are teaming up to manufacture diesel hybrid trucks for a national program serving the utility industry. This reportedly is the largest diesel hybrid pilot program to date, testing a minimum of 20 trucks using an integrated powertrain developed jointly by the two companies.

The selection was announced at the Hybrid Truck Users Forum (HTUF) operated by WestStart, an advanced technology consortium bringing together truck fleet users, truck makers, technology companies, and the U.S. military. It was a Task Force of the Utility Working Group of HTUF that established the project, determined the requirements and issued the RFP (Request for Proposal) that resulted in the selection of International and Eaton. Fifteen utility fleets have committed to participate so far. (The key performance parameters are here. The RFP is here.)

Among the key requirements are an approximately 50% reduction in fuel consumption and meeting the EPA 2010 emissions targets.

“This project takes hybrid truck systems to the next level of commercialization,” said John Boesel, President and CEO of WestStart-CALSTART, which operates the Hybrid Truck Users Forum program in a partnership with the U.S. Army’s National Automotive Center (NAC). “These are not prototype trucks. They are the early production versions of what we expect will be commercially available trucks in the next two to four years.”

The national Hybrid Truck Users Forum (HTUF) is a joint program between WestStart-CALSTART and the NAC to speed the commercialization of hybrid drivelines that could be used in both military and commercial vehicles.

If the pilot program is successful and customer needs are met, International is prepared to produce diesel-electric hybrid trucks as early as 2006.

The initial powertrain couples an International in-line six-cylinder diesel engine with an Eaton hybrid-electric drivetrain, which includes transmission, batteries and electric motor. This appears to be a series hybrid approach, with power from the engine converting directly into electrical energy to power the truck. The hybrid system uses regenerative braking to charge the batteries. The batteries can also provide an extra boost for acceleration. Additionally, the hybrid truck used in the pilot will operate the utility bucket in an electric-only mode, with the engine shut off, for up to 2 hours and provide electric power during idling for added fuel saving benefits.

Eaton is also involved in another diesel-hybrid pilot on delivery vans with FedEx.