When fleets join EPA’s SmartWay Partnership, they voice their intention to limit exhaust emissions and report regularly on their activities in this regard, but it’s definitely not a one-way street. SmartWay, in turn, is obligated to assist partners in achieving emission and fuel usage reduction goals.
To do this, EPA, working with OEM partners, has identified a group of vehicle designs and equipment that, taken together, can help fleets reduce fuel consumption. Because Class 8 tractor-trailer combinations used in line haul applications typically use the most fuel of any heavy-duty truck, they were the program’s first target. Therefore, SmartWay specifications are only available for such vehicles at this time, but these specs are very useful. SmartWay certified combinations can achieve fuel savings of 10% to 20% (saving carriers between 1,700 and 3,300 gal. of diesel fuel annually), lower greenhouse-gas emissions, and significantly reduce oxides of nitrogen and particulate matter.
SmartWay certification for trucks and trailers is a design-based specification developed on this basis of test results for individual components (tires, wheels, aerodynamic equipment, auxiliary power units, engines) that have been demonstrated to improve fuel efficiency and reduce emissions. When manufacturers equip long-haul tractors and trailers with these specifications, they are labeled “U.S. EPA Certified SmartWay.” For a list of both truck and trailer suppliers that offer SmartWay certified vehicles, visit www.epa.gov/smartway.
To develop these criteria, SmartWay has used a well-accepted fuel economy test originally developed by the Technology and Maintenance Council and the Society of Automotive Engineers. The test procedure was originally developed to determine the fuel-saving potential of individual components. Component testing alone is not sufficient, since the fuel-saving impacts can vary based upon vehicle application. However, a standardized, objective, stand-alone fuel efficiency test to measure the fuel efficiency of a heavy-duty on-highway vehicle does not currently exist.
SmartWay is therefore currently working toward a performance-based specification that will be technology-neutral and capable of being used to test a broad range of vehicle configurations and applications, and to measure the fuel-saving potential of technical innovations as they emerge. Without a new test method, it is difficult to develop a common understanding of how to assess and compare the fuel efficiency of heavy-duty vehicles, including vehicles with hybrid powertrains, varying aerodynamic configurations and other advanced designs. The procedure will provide test methods that are appropriate for a number of different truck types, based on the specific application or service category.
The proposed test protocol measures fuel consumption directly in terms of fuel consumed per unit of work performed (for example, for line haul trucks, gallons-per-mile or per- ton-mile; for vocational trucks with power takeoff, gallons-per-hour). A fuel consumption, rather than a percent improvement metric, allows for a stand-alone efficiency measure for any given truck model. It also provides a consistent, standardized means to compare the fuel efficiency of two or more tested trucks.
Designed to be applicable to a conventional internal combustion engine or a hybrid power train, the proposed procedures define various test requirements and methods depending on vehicle type, based on a classification according to service category or vehicle application. These categories cover many common types of heavy-duty vehicle applications with the greatest near-term potential to benefit from fuel-saving technology:
• Highway line haul combination tractor-trailers
• Regional haul combination tractor-trailers
• Local pick up and delivery trucks (e.g., parcel, beverage)
• Neighborhood refuse trucks
• Utility service trucks
• Transit buses
In the not-too-distant future, fleets operating vehicles in these applications will likely have the opportunity to select vehicles tested and certified as highly fuel-efficient. After the expanded program is in place, just look for the “US EPA Certified SmartWay” label on the P&D truck you’re thinking of buying.