Are shore power and emission control area policies always effective together for pollutant emission reduction? – An analysis of their joint impacts at the post-pandemic era

Abstract

Shore power (SP) and emission control area (ECA) have been two of the main polices for a green maritime logistics. However, it is still not clear how the joint impact of these two polices will influence vessels' shipping and energy consumption plan. The influence could be more complicated at the post-pandemic era of COVID-19 when the vessel's refueling could be risky. This paper develops mathematical model of the vessel's routing and fuel inventory decisions by considering both the SP and ECA. Based on the model, we analyze the optimal decision of a vessel under three different policy conditions, which are non-SP, compulsive utilization of SP at all ports, and optional SP utilization by the vessel. The numerical experiments are conducted based on the information of a vessel delivering cargos along the coastline in China. The results uncover a novel phenomenon that the implementation of the SP might incentive the vessel to travel longer distance outside the ECA for a lower total cost that results in more pollutant emissions. We show that the SP policy would influence the vessel's fuel management and refueling times which can change the route of vessel sailing inside and outside ECAs. Sensitivity analysis also shed light on how the government's decision on the SP policy may influence the overall pollutant emissions of the vessel from both berthing at ports and sailing on the sea. We discussed how the fixed cost of refueling, which is affected by the risk of the COVID-19 condition, will influence the vessel's plan under the SP and ECA polices. This study suggests the government to make an integrated policy of both SP and ECA at the post-pandemic era to achieve an overall reduction of the pollutant emission.