Environmental impacts of the transition to automated vehicles: A life cycle perspective

Abstract

The environmental benefits and burdens of connected and automated vehicles (CAVs) are still a subject of debate in the existing literature. This research aims to address this gap by conducting a life cycle assessment of CAVs, focusing on different transition phases in terms of the associated traffic operations and environmental impacts. A micro-simulation was carried out on a specific roadway section, considering varying CAVs market penetration rates (MPR) and traffic volumes, assuming all vehicles were powered by internal combustion engines. The findings revealed that the most optimal traffic and environmental performance occurred when the MPR ranged between 70 and 80%. Notably, the use phase contributed to 90% of greenhouse gas (GHG) emissions and energy consumption. In comparison to the baseline conditions, the production phase experienced a 5% increase in CAV emissions, while the end-of-life phase saw a 1.5% increase. Conversely, emissions during the use phase decreased by 5%. Sensitivity analysis indicated statistically significant outcomes at higher traffic congestion levels, indicating that CAVs improved traffic operations and mitigated environmental impacts during periods of heavy traffic.