Glenn E. Futrell Distinguished University Professor North Carolina State University, North Carolina
Abstract Description: The 2018 Critical Review of the Air & Waste Management Association, “Trends in onroad transportation energy and emissions,” focused on historic and recent developments and trends relating to on-road vehicles. The review covered major advances in engine design, control technologies, and fuels that have made it possible to reduce emissions and fuel use despite sustained growth in on-road vehicle miles travelled. This paper provides a partial update of the 2018 critical review, focusing on onroad light duty vehicles, with regard to trends since 2018 in: (a) vehicle sales and vehicle inventory; (b) vehicle-miles traveled; (c) energy consumption; (d) CO2 emissions; and (e) emissions of criteria pollutants and precursors. Recent trends in light duty vehicle fuels, energy sources, and powertrains, and autonomous vehicles are identified and discussed. Powertrains include internal combustion engines, hybrid electric vehicles, plug-in hybrid electric vehicles, and battery electric vehicles. Recent developments in vehicle fuel economy and emissions regulations and incentives to decarbonize light duty onroad vehicle transportation are considered. Emerging issues related to changing vehicle technology and operation are also identified and discussed, including life cycle implications of battery manufacturing and recycling as well as the ecological impacts of tire wear particles. The implications of this update are evaluated with respect to opportunities to influence future trends in vehicle energy use and emissions.
