Optimizing Freight Routes and Modes to Minimize Environmental Impacts: Integrating Truck Emissions Cost in Traffic Assignment. Final Report.

摘要

Adverse impacts of greenhouse gasses (GHG) and the imperative for reducing the production are well established. The transportation sector accounts for 28% of all U.S. GHG production. Heavy-duty vehicles (e.g., large freight trucks) account for nearly 1/5 of the U.S. total and this fraction is growing. Most current efforts emphasize one of four areas: (1) engineering improvements to improve fuel economy or reduce emissions, (2) shifts to other transport modes, (3) improved logistics to reduce the movement of partially full or empty containers, and (4) reduced travel costs for individual trucks. A small fraction of studies have assessed modifications to route choice considerations as a means of improving fuel economy of individual vehicles. These studies suggest the potential gains are very small. In this study, potential gains of emissions-based route choice were assessed by integrating the EPA Motor Vehicle Emissions Simulator (MOVES) with a macroscopic regional traffic demand model. For this integration, route choices included a simplified emission calculation within the repeated model iteration runs of a Frank-Wolfe type algorithm. Analyses suggest reductions of freight truck emissions are possible and show an example where the total systems truck emission was reduced by up to 0.61% (88.8 tons).