Potential of cold-ironing for the reduction of externalities from in-port shipping emissions: The state-owned Spanish port system case

This paper provides insights into the potential of cold-ironing for the reduction of externalities. External cost derived from the emissions of CO₂, NO_x, SO_x, and PM from berthed ships in the Spanish port system during 2016 are estimated providing a Spain-wide empirical evidence into where the highest externalities exist and where, on a port by port level, the introduction of cold ironing could yield the highest potential on reducing said externalities. The combined overall external costs from both local and global effects of shipping emissions from berthed vessels were between 326 and 440 million Euro. Eco-efficiency parameters are also obtained. It is found that the population in the port city as well as the composition of traffic are key factors when the external costs are determined, and they should be considered when the investment decision about where cold ironing should be placed is taken.