A Review on Energy, Environmental, and Sustainability Implications of Connected and Automated Vehicles

TL;DR

This review explores how connected and automated vehicles impact energy use and the environment across multiple societal levels, emphasizing the importance of system-wide analysis for sustainable adoption.

Contribution

It provides a comprehensive analysis of environmental implications of CAVs at four system levels, highlighting the need for holistic assessment beyond vehicle efficiency.

Findings

Net positive impacts at vehicle, transportation, and urban levels

Societal shifts may offset environmental benefits

System-level analysis is crucial for sustainable CAV deployment

Abstract

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 in order to envisage and address concerns regarding the short- and long-term sustainable adoption of CAV technology.