Analysis of technology options to reduce the fuel consumption of idling trucks

Market concepts, competing technologies and cost challenges for automotive and stationary applications

“…The total cost of idling heavy-duty trucks in the US is over a billion dollars per year for fuel and extra maintenance. [19] An attractive APU that could replace the main engine is a diesel-fueled fuel cell. Two types of fuel cells could run on diesel fuel: proton-exchange membrane fuel cells of the type being developed for cars, with a device to convert the diesel fuel to hydrogen, or solid-oxide fuel cells that can operate directly on diesel fuel.…”

Technology Roadmap for the 21st Century Truck Program, a government-industry research partnership

“…Auxiliary power needs and requirements are also strongly influenced by power requirements of line-haul Class 8 trucks. An estimated 458,000 Class 8 trucks travel farther than 500 miles from their home base each day and are likely to be idling during overnight stopovers (Stodolsky, Gaines, and Vyas 2000). Assuming an average of six hours of idle time per day, this represents 566 million truck-hours of idle time per year.…”

“…Idling to generate auxiliary power has a significant impact on overall vehicle fuel efficiencies and emissions. For example, an estimated 838 million gallons of fuel is consumed and 9.6 million tons of CO 2 is emitted annually for line-haul trucks idling overnight to heat or cool the cab/sleeper, operate electrical accessories, and keep the fuel and engine warm in the winter (Stodolsky, Gaines, and Vyas 2000). U.S. government hours-of-service regulations that are pending could require Class 8 line-haul drivers to decrease the number of hours on the road per day and increase frequency and length of rest periods.…”

“…One technology being developed to reduce engine idle of Class 8 trucks during rest periods and to meet future truck electrical power requirements is the auxiliary power unit (APU) (Stodolsky, Gaines, and Vyas 2000). Auxiliary power units for Class 8 tractor-trailers are available today that are capable of generating electrical and mechanical energy, independently of the truck engine operation.…”

“…High market penetration of auxiliary power units, to reduce Class 8 truck engine idle during rest periods would have a dramatic effect on fuel usage and emissions. It has been estimated that APUs could reduce auxiliary fuel usage and emission by upwards of 80% (Stodolsky, Gaines, and Vyas 2000).…”