Delphi and Peterbilt Motors Company successfully demonstrated a Delphi solid oxide fuel cell (SOFC) auxiliary power unit (APU) powering a Peterbilt Model 386 truck’s “hotel” loads. During recent testing at Peterbilt’s Texas headquarters, the Delphi SOFC provided power for the Model 386’s electrical system and air conditioning and maintained the truck’s batteries — all while the Model 386’s diesel engine was turned off.
This demonstration, held in June, leveraged development supported by the U.S. Department of Energy’s Energy Efficiency and Renewable Energy
(EERE) and Fossil Energy Solid State Energy’s Conversion Alliance
Delphi’s SOFC technology directly addresses increasingly stringent anti-idling legislation and other proposals addressing commercial truck emissions, noise and fuel consumption.
Delphi’s SOFC converts chemical energy in conventional fuels directly into useful electrical power without combustion. A SOFC operates quietly and at a higher efficiency level than traditional internal combustion engines. By limiting idling time and running a SOFC instead of the main engine, emissions are reduced, noise is nearly eliminated, and operators realize significant fuel savings.
The new Delphi technology will have the capability of using a variety of fuels, including natural gas, diesel, bio-diesel, propane, gasoline, coal-derived fuel and military logistics fuel. In addition to its fuel flexibility, the SOFC will be compact in size.
The Peterbilt/Delphi test replicated a typical trucker’s day to evaluate the real-world usefulness and capacity of the SOFC:
— To begin, the SOFC APU was brought to operating temperature with the
truck’s main engine running. This simulated starting the SOFC APU during
normal, on-road driving conditions.
— Once the SOFC APU was at temperature and available to provide power,
the Model 386’s main engine was turned off, simulating the beginning of a
— During the rest period, the SOFC APU powered the 386’s electrical
loads, including the electric air-conditioner, radio, citizens band radio,
and lights. It also charged the truck’s battery.
— After 10 hours (representing running overnight) the Model 386’s main
engine was restarted to simulate the driver beginning his drive for the
Throughout the test, the SOFC APU provided an average of 800 watts of electricity to the Peterbilt Model 386.
“The Delphi SOFC passed this test, standing up to the demands of a typical truck-driver’s day,” said Mary Gustanski, Delphi Powertrain Systems director of Engineering. “We are encouraged by the performance of the demonstration, especially given the 95-degree-F Texas heat. Additionally, we thank everyone at Peterbilt for participating in this evaluation and for echoing our enthusiasm for the further development of eco-friendly solutions.”
“The SOFC system provides a technologically-advanced solution to meet anti-idle requirements while surpassing expectations for reduced emissions, noise and fuel consumption,” said Landon Sproull, Peterbilt Chief Engineer. “This system has the potential to revolutionize future APUs by setting new benchmarks for performance and ease of operation with no adverse effects on the environment.”
The Peterbilt Model 386 was chosen as the test bed for the SOFC due to its aerodynamic and fuel-efficient performance. It merges conventional Peterbilt styling with leading aerodynamic design and has been recognized as fuel efficient and environmentally friendly by the EPA’s SmartWay program.