Review of hybrid ship propulsion systems: energy strategies, simulation platforms, and future challenges

With growing global attention to decarbonization and sustainable development, ship propulsion systems are undergoing a significant transition toward enhanced energy efficiency and reduced environmental impact. Hybrid ship propulsion systems, which integrate multiple energy sources such as LNG, hydrogen, and solar energy, have gained increasing attention in the maritime industry for their potential to reduce fuel consumption and emissions. However, the complexity associated with energy source configurations in hybrid ship propulsion systems, energy distribution and management, and simulation platform selection poses considerable challenges to the effective implementation of such systems. To address the above issues, this paper first reviews the development of ship propulsion systems. It then outlines the main energy sources applied in hybrid ship propulsion systems, including conventional fossil fuels, transitional fuels, and sources supporting zero-emission onboard operation. Furthermore, various types of energy management strategies (EMSs) for hybrid ship propulsion systems are summarized and compared. The simulation platforms, including GT-POWER, AVL Cruise M, Simcenter Amesim, and Simulink, are evaluated and compared to highlight their applicability and suitability under various scenarios. In addition, representative hybrid ship projects and their practical applications are introduced, including key demonstrations and their commercial use cases. Finally, the key challenges and future development trends of hybrid ship propulsion systems are discussed, providing a comprehensive reference for researchers, ship designers, and shipowners to further promote both academic research and practical deployment of hybrid ship propulsion systems.