Heavy Duty Longhaul:
The heavy-duty hybrid electric Model 386, configured for on-highway use, is being developed in conjunction with Eaton and Wal-Mart Stores, Inc. It is currently in the testing and evaluation phase and is expected to be available in 2010.
The system features an automated manual transmission with a parallel-type "direct" hybrid system, incorporating an electric motor/generator located between the output of an automated clutch and the input to Eaton's Fuller UltraShift transmission. The system captures energy generated by the diesel engine and recovers energy normally lost during braking and stores the energy in batteries. That electric torque is then sent through the motor/generator and blended with engine torque to improve vehicle performance, operate the engine in a more fuel-efficient range for a given speed and/or operate only with electric power in certain situations.
Medium Duty Hybrid Electric:
Peterbilt and Eaton has engineered a hybrid electric system, for its Class 6 Model 330, configured for local pick-up and delivery applications, and its Class 7 Model 335 equipped with a fully integrated Terex bucket lift body.
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 P&D work, with the hybrid system resulting in 30 to 40 percent greater fuel savings by using electric power to accelerate the vehicle from a stop, according to Peterbilt
The Model 335 is also powered by the PACCAR PX-6 engine which regenerates lithium-ion batteries to electrically operate the PTO. This application of hybrid technology is well suited for municipal and utility applications.
Both medium duty hybrid trucks are in limited production this year with full production expected for 2008.
Heavy Duty Vocational Hybrid Hydraulic Vehicle:
finally, the hybrid Hydraulic Launch Assist (HLA) technology is currently being evaluated for vocational and stop-and-go applications, such as refuse collection.
The system, currently integrated with Peterbilt's low-cab-forward Model 320, increases brake life and reduces engine and transmission wear, potentially extending component life and lowering service costs. HLA works by recovering a portion of the energy normally lost as heat by the vehicle's brakes, in the form of pressurized hydraulic fluid. This fluid is stored in on-board accumulators until the driver next accelerates the vehicle.
Fuel savings occur when the stored energy is then used to launch the vehicle during the initial, high fuel consumption start from stop, followed seamlessly by power from the primary engine. In performance mode, the stored energy is released and blended with engine power at launch. This can significantly improve acceleration due to the high power density of hydraulics.