Connected & autonomous vehicles - Environmental impacts - A review.

Over the last decades the vehicle industry has shown interest in integrating new technologies on vehicles' design. Such technologies are used in autonomous, connected and electrical vehicles with the primary hope of improving road safety and the environmental impact of road traffic. Regarding the environmental impact, the transport sector has been considered responsible for Greenhouse Gas emissions for the past thirty years or more, and efforts have been made to reduce impacts of such emissions on the environment. The environmental noise is also associated with road traffic and its effects on public health, along with ways of scaling them down, have been under investigation. Taking into consideration worldwide efforts on climate change and new vehicle technologies that are being introduced, this paper provides a review on the studies concerning the environmental and traffic noise impacts anticipated by the implementation of these kinds of vehicles in the market and in road traffic. Two types of studies, conducted the last 10 years, are included in this review: a) studies that use logical estimates to draw conclusions on how Connected and Autonomous Vehicles (CAVs) as well as Electrical Vehicles will alter fuel consumption, gas emission, etc., and b) studies that make use of mathematical frameworks and the data available to extract numerical results. Eleven (11) factors affecting CAVs' environmental impacts were found and categorized based on whether they are related to the vehicle, the road network or the user. A comparison of the different procedures is attempted, in order to identify the factors that are influencing the emergence of anticipated environmental impacts as well as their variety and extent.