Peterbilt Medium Duty Hybrid vehicles will launch into full production as early as March of 2008, the company announced during its press conference at the 2007 Great American Trucking Show.
Peterbilt will offer two medium duty hybrid configurations – the Model 330 hybrid electric for pick-up and delivery applications and the Model 335 hybrid electric for stationary PTO applications.
“Peterbilt continues to be an industry leader in developing advanced hybrid solutions that increase fuel efficiency, reduce emissions and improve service requirements,” says Bill Jackson, Peterbilt General Manager and PACCAR Vice President. “In fact, customers who have already implemented our medium duty hybrid systems into their operations have reported significant results of up to 40% greater fuel savings.”
Medium Duty Hybrid Electric Vehicles
Peterbilt’s Class 6 hybrid electric system, developed in conjunction with Eaton Corporation, is a Model 330 for pick-up and delivery applications.
The Model 330 is powered by the PACCAR PX-6 engine rated at 240 horsepower and 560 ft-lbs of torque. With the hybrid system engaged, horsepower increases to 300 and torque to 860 ft-lbs. This configuration is ideal for stop-and-go use, such as urban pick-up and delivery, with the hybrid system resulting in 30 to 40 percent greater fuel savings by using electric power to accelerate the vehicle from a stop.
Peterbilt’s Class 7 hybrid electric system is a Model 335 for stationary PTO applications. The Model 335 is also powered by the PACCAR PX-6 engine which regenerates lithium-ion batteries to electrically operate the PTO, ideal for municipal and utility applications. Fuel use, emissions and noise are greatly reduced. During typical stationary operation of the PTO, the engine needs to run only about 1/6th of the time versus non-hybrid vehicles. The engine automatically starts to regenerate the batteries, which takes approximately 4.5 minutes.
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Both trucks use a parallel hybrid system with an electric motor that assists the mechanical diesel engine with supplemental torque for improved fuel economy. The system stores energy during stopping through a process called regenerative braking, and then reuses it for acceleration. In the case of the Model 335, in which the vehicle is equipped with a PTO, the system also stores energy during idling to power the PTO.
Maintenance requirements are also reduced from less wear on the engine and the brakes, as its workload is supplemented by the electric motor and the charging of the battery retards the motion of the vehicle.
In addition to Peterbilt’s two medium duty hybrid vehicles, the company is also actively developing and testing technology for two heavy duty hybrid configurations – a hybrid electric heavy duty vehicle for long-haul applications and a hydraulic hybrid heavy duty vehicle for vocational and stop-and-go applications.
On-Highway Hybrid Electric Vehicle
The first heavy duty hybrid initiative includes the evaluation of an on-highway hybrid electric vehicle – an aerodynamic Model 386 configured for long-haul applications developed in conjunction with Eaton and Wal-Mart Stores, Inc. The Model 386 hybrid system has achieved a 5-7 percent fuel savings over non-hybrid models in third party testing.
“In this heavy-duty application, fuel efficiency and emissions reductions are best achieved both while the truck is rolling or standing still,” says Peterbilt Chief Engineer Landon Sproull. “The system’s batteries power the heating, air conditioning and vehicle electrical systems while the engine is off,” Sproull said.
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When the idle reduction mode is active, engine operation is limited to battery charging, an automatically controlled process that takes approximately five minutes per hour to fully charge the system. A proprietary feature minimizes engine vibration during start-up and shutdown during the recharge periods, allowing the driver to rest without interruption.
The Model 386 hybrid electric is expected to be available in 2010.
Heavy Duty Vocational Hybrid Hydraulic Vehicle
Peterbilt continues development of hybrid Hydraulic Launch Assist (HLA®) technology, currently being evaluated on Peterbilt’s low-cab-forward Model 320, for vocational and stop-and-go applications such as refuse collection.
The system recycles a truck’s kinetic energy to conserve fuel and assist in acceleration. While in fuel economy mode, testing has proven a significant improvement in fuel efficiency and has also shown more than a 50 percent reduction in brake wear. The system also reduces engine and transmission wear, potentially extending component life and lowering service costs. It is also more environmentally friendly by decreasing exhaust emissions and noise.
The Model 320 hydraulic hybrid is expected to be available in late 2008.
[source: Peterbilt]