Fixed or mobile shore side electricity? A comparative analysis considering berth allocation and quay crane assignment

Shore side electricity (SSE) is an effective measure for reducing greenhouse gas (GHG) emissions from ships during port stays. However, conventional fixed SSE systems may lead to some additional emissions in actual port operations. To address this issue, we propose the use of mobile SSE systems, which can mitigate such negative impacts. This study constructs an SSE allocation optimization model, considering berth allocation and quay crane assignment problem (BACAP). An adaptive genetic algorithm (GA) is employed to solve large-scale problems. The performance of the proposed algorithm is benchmarked against commercial solvers and other heuristic algorithms. Results of comparative tests demonstrate that mobile SSE performs no worse than fixed SSE in all scenarios, with significant advantages in emission reduction, particularly under high ship traffic density or when the proportion of SSE vessels is high. In addition, sensitivity analyses are conducted on electricity prices and carbon taxation. Moreover, the analysis reveals that the movement time of mobile SSE has a negligible effect on its overall superiority. Based on the findings, recommendations for SSE development are made to the government and ports in response to the findings of the study.