Operating between ports inside and outside emission control areas and its effect on shipping cost

Abstract Emission Control Areas (ECAs) have been established to mitigate the environmental impact of maritime transportation, significantly affecting ship operations and costs. While previous studies have examined optimal sailing strategies within ECAs, most have been limited by the inability to provide precise latitude and longitude coordinates for the optimal sailing path. Furthermore, there is limited research on scenarios where ships operate between ports inside and outside ECAs, a common occurrence in global shipping. This study addresses these gaps by investigating the optimal sailing patterns for ships operating between ports located inside and outside ECAs. A mixed integer nonlinear programming model is developed to minimize fuel costs while complying with ECA regulations, determining optimal speeds inside and outside the ECA and latitude and longitude coordinates of ECA entry/exit point. By analyzing 204 routes in the Atlantic Coast and Gulf of Mexico ECA, this study reveals that sailing pattern optimization is economically beneficial on over 76% of routes, a higher proportion than scenarios where both ports are within ECAs. Two critical factors influencing optimal sailing pattern selection are identified: the proportion of the sailing distance inside the ECA to the total sailing distance under the original sailing pattern (S) and fuel price ratio inside and outside the ECA. Unlike the scenario where both ports are within ECAs, S emerges as the primary determinant of strategy selection. This finding contributes to the understanding of ship behavior under ECA regulations in more complex routing scenarios and provides valuable insights for both shipping operators and policymakers.