EPRI Project Improves Emissions Estimates for On-Road Vehicles
An EPRI project has refined the methods used for calculating emissions for on-road vehicles.  In a modeling study for the Detroit and Atlanta regions, researchers put the updated on-road emission factors and usage patterns into the newest EPA vehicle emissions model, MOVES, and found large increases in particulate matter (up to a factor of four in light-duty gas vehicle emissions), particularly in wintertime, and large increases in NOx, particularly in summertime.  Now that the MOVES model is officially required for use by states and regions for future State Implementation Plan development, these refinements are expected to have significant impacts on air quality compliance modeling.  These results were presented at the March 22–24 Coordinating Research Council On-Road Vehicle Emissions Workshop, and a paper is being prepared for journal submission.  For more information, contact Stephanie Shaw, (650) 855-2353, sshaw@epri.com.