SmartWay Applications for Drayage Trucks (TTI-2009-5)

Drayage trucks operating daily across the border between the United States and Mexico can be a significant source of emissions, which negatively impact air quality. The U.S. Environmental Protection Agency's (EPA's) SmartWay Transport Partnership program helps to reduce fuel usage and emissions from freight operations through the use of technologies and best practices. This project tested the emissions and fuel-economy performance of three SmartWay strategies (use of lighter trailers, modified driving behavior [eco-driving], and use of diesel oxidation catalysts [DOCs]) for border drayage operations. Researchers tested five drayage trucks using portable emissions measurement system (PEMS) units before and after implementation of a SmartWay strategy. PEMS collected second-by-second emissions of oxides of nitrogen (NOx), hydrocarbons (HC), carbon monoxide (CO), particulate matter (PM), and carbon dioxide (CO2). CO2 emissions served as a proxy for fuel-consumption testing. Researchers also tested a fuel-combustion enhancer from Carbon Chain Technologies Limited. The company's 2ct® product was tested in light-duty gasoline vehicles and heavy-duty diesel vehicles for fuel economy and emissions, and may have potential for future applicability for emissions-reduction efforts and for SmartWay. Two PEMS units measured the gaseous (CO2, CO, NOx, and total HC [THC]) and PM emissions rates, and the EPA's Motor Vehicle Emissions Simulator (MOVES) model analyzed the results. The study showed that DOCs provide major THC- and CO-reduction benefits for drayage operations. Lightweight trailers and eco-driving also decrease CO and THC emissions moderately. Only eco-driving appears to have a positive impact on CO2, fuel consumption, and NOx emissions. All the investigated strategies resulted in lowering PM emissions compared to the baseline.