An integrated collaborative decision-making method for optimizing energy consumption of sail-assisted ships towards low-carbon shipping

Abstract

Energy conservation and emission reduction have become an urgent and important issue for the shipping industry in the context of low-carbon shipping. For sail-assisted ships, the application of wind energy can reduce energy consumption and thus greenhouse gas emissions. However, there still exists a high potential for energy efficiency improvement due to the lack of an effective optimization method for maintaining the hybrid system operating at the optimal state continuously. In this paper, a novel integrated collaborative decision-making method, considering the coupling influence of the sailing path, speed, wing-sail's angle of attack, and various environmental factors, is investigated to achieve energy conservation and emission reduction for sail-assisted ships. First, an integrated collaborative optimization model of the sailing path, speed, and sail's angle of attack is established. On this basis, a PSO-based integrated collaborative decision-making method for simultaneous optimization of sailing path, speed, and sail's angle of attack under various operational conditions is proposed. The study results show that the proposed method is capable of fully utilizing wind energy, meanwhile maintaining the hybrid power system operating at the optimal state under various operational conditions, and can reduce energy consumption and CO2 emissions by approximately 8.9% for a voyage.