FONTANA, CALIFORNIA…Freightliner Trucks demonstrated an application of fuel cells for heavy-duty trucks at the Michelin Challenge Bibendum event here. In the Freightliner demonstration, fuel cells are used to power the comfort and convenience accessories on a parked heavy-duty truck. This cuts the need to idle the engine, thus reducing fuel consumption, emissions and noise. The fuel cell auxiliary power unit is installed on a Freightliner Century Class S/T heavy-duty truck, one of the most popular Class 8 truck models in North America. The Michelin Bibendum is an independent, real-world demonstration of environmentally-innovative trucks and automobiles.
“Freightliner’s fuel cell demonstration truck shows an alternative for powering auxiliary devices on a parked heavy-duty truck instead of idling the engine,” said Gary Rossow, Director of Government Technical Affairs for Freightliner LLC. “This technology has great potential for increasing the comfort and efficiency of long-haul trucks, while reducing their environmental impact.”
Today’s heavy-duty trucks can be equipped with cab heaters, air conditioners, on-board computers, televisions, stereos, refrigerators, microwave ovens and coffee pots -- all of which require electrical power.
To power these devices while the truck is parked, drivers often must idle the engine. The Department of Energy has estimated potential, annual fuel and maintenance costs related to idling a heavy-duty truck at $1,800. Idling also produces emissions, as well as increases noise levels inside the cab and sleeper.
The Freightliner demonstration truck significantly reduces idling time by utilizing a fuel cell auxiliary power unit to deliver electrical power.
Freightliner developed the system with XCELLSIS. It includes two Ballard fuel cell “stacks” operating as an auxiliary power unit (APU). The stacks are housed on the left side of the truck along the frame rails.
The Freightliner demonstration truck uses proton exchange membrane (PEM) fuel cells. The fuel cells are fed with hydrogen from a 52-gallon tank on the left side of the truck. Within the fuel cell, hydrogen is split into positively charged protons and negatively charged electrons. The protons can pass through the membrane, but the electrons cannot, so a voltage builds up in the fuel cell. The only by-product of this process is pure liquid water.
The fuel cell APU produces over 1.4 kilowatts (kw) 120 volts AC or 12 volts DC power. The APU is connected to the vehicle's electrical system through an 1800-watt inverter, which takes electricity from the fuel cells, batteries and alternator, and provides power to vehicle accessories/batteries in the required form (12v dc or 120v ac). The system is able to support a variety of power-consuming products up to the total system wattage limits.
“With the fuel cell auxiliary power unit, the truck driver can run the heater, listen to the stereo and use other appliances without idling the engine and without draining the battery,” Rossow said.
Freightliner is supporting efforts to make fuel cell auxiliary power units commercially viable. Challenges to be overcome include the availability and infrastructure of a suitable fuel for the fuel cell, the production cost of the units and integration of the unit with other on-board truck systems.
“While there are technical and economic issues to be addressed before these systems become cost-effective, this technology has great potential for increasing the productivity of trucking companies, improving the quality of life of truck drivers and providing environmental benefits,” Rossow said. “Freightliner will continue to explore and develop technologies that enhance the safety and reduce the environmental impact of commercial trucks.”
The fuel cell auxiliary power unit is a product of the efforts and support of Freightliner, affiliated companies, and the U.S. DOT’s Advanced Vehicle Program through West Start, a regional technology consortium.
Freightliner Trucks is a division of Freightliner LLC, headquartered in Portland, Oregon, and is the leading heavy-duty truck manufacturer in North America. Freightliner Trucks produces and markets Class 3-8 trucks and is a DaimlerChrysler company, the world's largest commercial vehicle manufacturer.