"Right-sizing" a fleet for better fuel economy requires considerable caution, since it can have its drawbacks as well as benefits. Many fleets, for example, have sought better economy from replacing larger trucks with smaller ones and/or switching to smaller-size power plants.
But, as the City of South San Francisco, Calif., discovered, smaller trucks may not always provide the room their operators require. In most instances, the City's switch from full-size pickups to compact four-cylinder Ford Rangers "worked out okay," said Keith Potter, public works supervisor for the City of South San Francisco.
However, where the Ranger's interior cab was too confining to accommodate, for example, the laptop computer and stand that service technicians required, officials were forced to switch back to full-size trucks.
SUV Hybrid: Popular, but Limited
The Hybrid Escape, Ford's small SUV, has gained considerable popularity as a means of improving economy, though its work capabilities are rather limited.
As one fleet manager, who has been replacing some of his vehicles with Hybrid Escapes, pointed out, "It's tough to find where the plug-in electrics will work."
Where used, hybrid trucks typically serve as transportation for work supervisors. Generally, the trucks are not very effective in improving fuel economy in work applications, where the truck must idle for lengthy periods or perform other work while idling. That's because the draw on the electrical system, such as running air conditioning, can eliminate the fuel economy benefits of the electrical backup.
Another fleet manager also pointed out that, "While there are a lot of grants out there for buying hybrids, I don't see the economical advantage at this moment. There are a lot of unknowns. And, when the lifecycle is up, what do you do with the battery? What about the cost of disposal? The environmental waste?"
New Eaton Technology
As one promising work truck alternative to conventional hybrids, Eaton has developed a new hydraulic launch assist system. Already tested by several fleets and most effective in stop-and-go applications, the system employs the truck's kinetic energy during braking to aid in launching and accelerating the truck.
It basically recovers most of the energy normally generated and then dissipated by the brakes, creating pressurized hydraulic fluid, which works to significantly improve fuel economy, as well as reducing emissions and prolonging brake life, according to company officials.
