Energy-efficient garbage trucks are in the works
40% increase in fuel economy is possible
By Bob Freund
OSHKOSH, Wis. -- Garbage trucks lead a start-and-stop life that drinks up diesel fuel as engines race and then idle, time and time again. In the future, an electric technology that Oshkosh Truck Corp. is developing promises both energy savings and quieter neighborhoods.
"You would probably hear a constant hum (from the truck's engine)," Oshkosh spokeswoman Kirsten Skyba said.
Oshkosh Truck, which makes its garbage truck bodies at Dodge Center, has won a $4.5 million grant from the National Renewable Energy Laboratory in the U.S. Department of Energy to design a hybrid electric-and-diesel drive system for refuse-collection trucks. Oshkosh also will spend $4.5 million on the three-year project under the matching grant.
Oshkosh already is well along in development of a hybrid drive, called ProPulse, for the heavy-duty military trucks it produces. The Wisconsin-based manufacturer has a working prototype and just landed a separate $500,000 cost-sharing grant from the Department of Defense.
The $1 million program will take a version of ProPulse to the point that it is ready for mass production in the military's trucks.
"There is little doubt that hybrid electric drive technology will lead to the development of an entirely new generation of highly mobile and incredibly efficient trucks," Oshkosh chief executive officer Robert G. Bohn said in a written announcement.
Under the Department of Energy grant, Oshkosh will research a hybrid electric drive system for refuse-collection trucks. The technology could increase fuel economy as much as 40 percent compared to conventional power trains in use today, the manufacturer announced. It also promises to reduce air emissions and enhance durability of trucks.
"Basically, your truck is a power generator," Skyba said. The generating system can provide enough juice for a city block or a field hospital, Oshkosh said in its written release.
The ProPulse design uses a diesel engine to power an electric generator, which turns the wheels. Each wheel is driven independently with a dedicated motor chassis. The system eliminates a number of mechanical components, including the torque converter, transfer case and drive shaft, among others.
Essentially, a diesel engine runs constantly at an optimum level, storing up energy in an "ultracapacitor" for the electric motors.
When the truck stops to collect and compact garbage, electric motors drive equipment, while the engine's excess energy is stored up to be used in the wheel motors during the next acceleration. The engine runs at a constant, efficient pace, Oshkosh says.
The hybrid drive is mounted on the chassis underneath the truck. To date, Oshkosh manufactures only the truck bodies and attaches them to frames made by other suppliers.
The federally backed research will focus on adapting ProPulse technology for garbage hauling uses in general.
But, "potentially, we do see benefits for the McNeilus product line (of refuse trucks) down the road," Skyba said.
Other Oshkosh-built trucks, such as snow plows, fire engines and rescue vehicles, also might benefit. "We believe that hybrid electric drive technology has applications in a number of industries," Skyba said.