PI-based energy management of a hybrid Wind–Fuel Cell–Battery system for low-emission marine vessels

Maritime transport is one of the largest sources of greenhouse gas emissions worldwide, creating an urgent need for cleaner and more efficient propulsion technologies. Conventional marine diesel engines remain the dominant power source but produce significant amounts of CO 2 , NOx, and SOx. This paper addresses the challenge of achieving stable and low-emission marine power generation. The main objective is to develop and evaluate a hybrid wind/FC/battery power system controlled by a PI-based energy management system (EMS), providing a low-emission and reliable power supply for marine applications. A complete simulation model was developed in MATLAB/Simulink to analyze the performance of a proton exchange membrane fuel cell (PEMFC), a lithium-ion battery, and a small onboard wind turbine. For performance evaluation, the proposed hybrid system is compared against a baseline fuel cell–battery configuration without wind integration under mission load conditions. The energy management system is structured as a multi-loop PI-based control architecture, and hydrogen consumption is quantified over the mission profile to assess the impact of wind-assisted power sharing. The EMS coordinates power sharing among the subsystems, maintains DC-bus voltage stability, and regulates the battery state of charge (SOC) within operational limits under dynamic marine load profiles. Simulation results indicate that the proton exchange membrane fuel cell supplies approximately 89.5% of the total energy demand, while the battery and wind subsystems contribute about 7.2% and 3.3%, respectively. The DC-bus voltage is maintained within ±5% of the nominal 750 V, and the battery state of charge remains within the operational range of 20%–80%. The hybrid configuration results in an overall hydrogen consumption reduction of approximately 4% compared to the baseline case, corresponding to a total hydrogen consumption of 153 kg h -1 . Variations of ±20% in wind speed lead to less than ±3% variation in hydrogen consumption, which indicates stable performance under the simulated operating conditions. The PI-controlled hybrid fuel cell/battery/wind system represents a feasible and low-complexity solution for green marine propulsion. The proposed system demonstrates potential to support maritime decarbonization goals by reducing fuel consumption and emissions while offering a scalable platform for future sustainable vessel designs.