Estimating benefits of C‐ITS deployment, when legacy roadside systems are present

Cooperative systems which rely on vehicle‐to‐infrastructure communications are designed to tackle important road transport issues, such as safety, traffic efficiency and pollution. Since the associated monetary commitment to invest is substantial, a clear understanding of the likely costs, impacts and benefits is necessary before investment decisions can be made. A tool for estimating the costs and benefits, from both business and the societal point of view, was developed in the ANACONDA project, ‘assessment of user needs for adapting COBRA including online database’, to assist National Road Authorities (NRAs) during their decision processes. This study presents an approach for determining societal benefits by taking into account the presence of legacy roadside systems, which affect the size of the benefit reaped when cooperative intelligent transport systems (C‐ITS) services are deployed. This study develops closed‐form solutions for determining benefits to NRAs, taking into account the presence of legacy roadside systems. The COBRA + Tool incorporates these aspects, enabling NRAs to carry out ‘what‐if’ scenarios for C‐ITS deployment. The study provides examples of application of the Tool.