Influence of external costs on the optimisation of container fleets by operating under motorways of the sea conditions

This paper provides a decision‐making tool for shipping companies that try to operate under motorways of the sea conditions by evaluating their environmental performance. From the definition and resolution of a mathematical model by assuming 'many to many' transport networks, the number of vessels, their manoeuvring means, speed, cargo handling systems and type of cargo units, along with the naval architecture and engineering of container ships, are defined to maximise the success opportunities for multimodal chains against the road. Due to the particularity of the technical and operative characteristics of the obtained vessels, the unquestionable environmental sustainability of short sea shipping is not self‐evident. The NSGA‐II algorithm has been applied to resolve this model as applied to multimodal chains between Spain and France. The findings reveal that optimised vessels are able to provide 'greener' multimodal chains than the road. However, the external costs in the seaborne are so significant that even surpass staff costs.