Identification and Testing of Emission-Reducing Technologies for Drayage Trucks
Project Description: More than 90 percent of all northbound freight transportation at U.S. border cities on the Mexican border is performed by drayage trucks, which engage in short hauls from warehouses on the Mexican side to warehouses in the U.S. sister city and then return to Mexico. These drayage trucks can be a significant source of emissions that negatively affect air quality.
The TCEQ/Border Affairs team contracted in 2008 with the Texas Transportation Institute, a Texas A&M research center, to study the typical "drive cycles" of drayage trucks in the El Paso-Ciudad Juárez area, establish a profile of the emissions generated during a drive cycle, and then test the costs and benefits of applying selected SmartWay technologies or strategies.
The EPA's SmartWay Transport Partnership program helps to reduce fuel usage and emissions from freight operations through the use of technologies and best practices. SmartWay strategies have until now been applied to long-haul trucking and not the short-haul operations found in drayage vehicles. This project tested the applicability of three SmartWay strategies—use of lighter trailers, modified driving behavior, and the use of diesel oxidation catalysts—for border drayage operations.
The El Paso-Ciudad Juárez area has a significant drayage truck circulation typical of other drayage activities along the U.S./Mexico border. El Paso is currently categorized as nonattainment for particulate matter (PM10) and it is anticipated that under new EPA rules it will soon be designated as nonattainment for ozone also.
TTI tested five drayage trucks, representing common makes and models, with portable emissions measurement systems (PEMS) before and after implementation of a SmartWay strategy. PEMS collected second-by-second emissions of oxides of nitrogen (NOx), hydrocarbons (HC), carbon monoxide (CO), PM, and carbon dioxide (CO2). CO2 emissions served as a proxy for fuel consumption testing.
TTI performed a cycle-based analysis using the drayage operation speed profiles that were developed. The final report concluded that using diesel oxidation catalysts provided major reductions in HC and CO. Lightweight trailers and modified driving behavior were found to reduce HC and CO moderately. Only modified driving behavior appeared to have a positive impact on CO2 and NOx emissions. All the investigated strategies resulted in lower PM emissions compared to the baseline.
The final objective of this project was to provide a broad range of stakeholders (drayage truck owners and operators and public and private sector organizations) with information on effective SmartWay technologies for drayage trucks, mainly through dissemination of the project report, which was completed in late 2009. TTI has publicized the findings at various conferences and meetings, including a quarterly meeting of the Joint Advisory Committee for the Improvement of Air Quality in the Paso del Norte (the JAC), and through a mailing of the report to federal, state, and local agencies, non-profit organizations, and trucking companies in the Paso del Norte area.
Following the presentation to the JAC, that body passed a resolution urging participating jurisdictions to find ways to offer training on "eco-driving" to drayage truck drivers. SEMARNAT (the federal environmental agency in Mexico) has responded and will offer a week-long course in Cd. Juárez in October 2010.