|International-Eaton Hybrid Utility truck|
Initial independent test results of prototype hybrid utility trucks being used in the WestStart’s Hybrid Truck Users Forum (HTUF) pilot program (earlier post) have shown a decrease in fuel consumption of 40%–60% measured against driving and work cycles typical of the utility industry. The target requirement for the hybrids was a 50% reduction in fuel consumption.
Larger-scale testing involving 24 of the hybrid utility trucks jointly developed by International and Eaton Corporation will begin by year’s end.
These early results are very promising. While we will need to test these trucks on a larger scale and over a longer period of time, we continue to see indications that these vehicles are commercially viable and will deliver real value to customers.—Bill Van Amburg, senior vice president, WestStart
These initial findings support our vision of making diesel-electric hybrid trucks a viable option. The other benefits we expect, such as extended maintenance intervals and fewer brake changes, further illustrate the promise of this technology.—George Survant, director of fleet services, Florida Power and Light Company; chairperson of the HTUF Utility Working Group
|Major components of the hybrid utility truck system|
The drive system in the utility trucks is in a pre-transmission parallel hybrid configuration, with a 44-kW permanent magnet motor mounted directly in front of the transmission, behind engine and clutch. Li-ion batteries provide the energy store.
The engine is a 6-cylinder 215-hp (160-kW) diesel that delivers 759 Nm of torque.
Power from the engine is used to drive the conventional drive-train directly or converted into electrical energy and stored for use as needed. Electric torque can be blended with engine torque to improve vehicle performance and to operate the engine in the most fuel-efficient range for a given speed or to operate the vehicle with electric power only.
The system recovers kinetic energy during braking, charging the batteries while the truck is slowing down which provides additional power for acceleration. This truck also can operate the utility bucket in electric-only mode, with the engine off, significantly contributing to improved fuel economy.