Fuel

Fuel-Cell Auxiliary Power Unit Project Wins Award

by Mary Wymer

A fuel-cell auxiliary power unit developed at UA runs some systems in long-haul trucks such as the one shown here.

A truck-mounted fuel-cell auxiliary power unit (APU), developed by UA's College of Engineering in a partnership with the U.S. Army TACOM National Automotive Center, Ballard Power Systems, and Freightliner LLC, recently was awarded the Automotive Engineering International Tech 2003 Award as one of the top technologies on display at the Society of Automotive Engineers' World Congress in Detroit.

While on display at the show, the environmentally friendly APU was producing power for various electrical components, including an air conditioning unit for the Class 8 Freightliner truck's large sleeper cab. The prototype APU generates power for onboard electronics and appliances.

There are many advantages and benefits of using a fuel-cell APU to provide auxiliary power. Military vehicles often run at idle, utilizing powerful engines at their lowest efficiency point, to provide relatively small amounts of electrical power for communications equipment, sensors, vehicle readiness, command and control, and basic amenity applications.

Similarly, long-haul commercial trucks idle their engines to power sleeper cabin heating and air conditioning, as well as a variety of other accessories during non-driving operations. Depending on the application and season, commercial trucks can idle anywhere between 20-40 percent of the time.

"Since this is the first prototype fuel-cell APU to be installed on a heavy-duty truck, the harmful vibrations that could result from road conditions were a major concern," explained Dr. Steve Shepard, assistant professor of mechanical engineering at UA.

As a result, UA researchers have been analyzing different vibration isolation techniques and studying various vehicle arrangements to minimize the impact of the vibrations on the APU. Researchers at UA also are studying system integration issues of the truck-mounted APU by examining its potential impact on vehicle efficiency.

Although little research has been conducted, it has been estimated that non-driving idling costs the commercial trucking industry nearly $2 billion per year in fuel costs alone. Truck engine idling also significantly increases vehicle emissions and noise levels.

These pollution and noise issues can be a major concern at truck stops where a large number of vehicles can be located within a small area. Many municipalities around the country have drafted anti-idling regulations. These regulations are expected to spread to other areas of the country and become more stringent in the future.

In addition to meeting these regulations, the reduced noise and emissions make the fuel-cell APU a prime candidate for applications where military personnel require a clean and quiet source of power. As a result, fuel-cell APUs offer the military and the commercial trucking industry the potential to substantially reduce fuel usage, vehicle emissions, and maintenance costs, by more efficiently and cleanly meeting these power needs.