Connected and automated vehicles (CAVs)
are poised to reshape transportation and mobility by replacing
humans as the driver and service provider. While the primary
stated motivation for vehicle automation is to improve safety
and convenience of road mobility, this transformation also
provides a valuable opportunity to improve vehicle energy
efficiency and reduce emissions in the transportation sector.
Progress in vehicle efficiency and functionality, however, does
not necessarily translate to net positive environmental
outcomes. Here, we examine the interactions between CAV
technology and the environment at four levels of increasing
complexity: vehicle, transportation system, urban system, and
society. We find that environmental impacts come from CAV-facilitated transformations at all four levels, rather than from CAV
technology directly. We anticipate net positive environmental impacts at the vehicle, transportation system, and urban system
levels, but expect greater vehicle utilization and shifts in travel patterns at the society level to offset some of these benefits.
Focusing on the vehicle-level improvements associated with CAV technology is likely to yield excessively optimistic estimates of
environmental benefits. Future research and policy efforts should strive to clarify the extent and possible synergetic effects from
a systems level to envisage and address concerns regarding the short- and long-term sustainable adoption of CAV technology.
School for Environment and Sustainability, University of Michigan, Ann Arbor, Michigan 48109, United States
Copyright: DOI: 10.1021/acs.est.8b00127 Environ. Sci. Technol. 2018, 52, 11449−11465. © 2018 American Chemical Society