If California’s emissions targets are to be met, zero emission vehicles (ZEVs) and near-zero emission vehicles (NZEVs) must be adequate substitutes for the conventional diesel truck, and realistic models that measure performance of ZEVs against diesel trucks are needed to inform policymakers of the required incentives for wide scale adoption of ZEVS. In this study, the researchers will use optimization and simulation modeling to explore the impacts of using battery electric heavy-duty trucks (BEHDTs) in freight operations (e.g., fleet size) and emissions, taking into account differences in performance and refueling. Specifically, they will focus on heavy duty trucks (HDTs) used in short-haul drayage services, one of the most promising market segments for early adoption. Drayage service is defined as short haul pick-up and delivery of goods to and from ports, warehouse and distribution centers, and intermodal facilities. The researchers will study scenarios with different mixture of diesel and battery electric heavy-duty trucks, and for each scenario will compute the minimum fleet size to meet the demand and the resulting emissions (e.g., PM2.5, NOX, and CO2). This work will build on an earlier study funded by the South Coast Air Quality Management District (SCAQMD).