A comprehensive review of emission reduction technologies for marine transportation.

This article provides a comprehensive review of decarbonization technologies in the maritime shipping industry, focusing on weather routing optimization, ship hull design, alternative power systems, and alternative fuels. It evaluates these technologies based on their potential to reduce greenhouse gas emissions and their economic feasibility, highlighting that hybrid power systems combined with alternative fuels such as liquefied natural gas (LNG), biofuels, hydrogen, and ammonia offer significant emission reduction opportunities. Weather routing algorithms and hull design improvements can contribute to fuel savings, though retrofitting existing vessels poses technical and economic challenges. The study concludes that LNG currently serves as a practical transitional fuel under existing regulations, while biofuels, hydrogen, and ammonia hold promise for long-term sustainability despite technical and regulatory barriers, recommending further research into hybrid propulsion systems integrating these fuels and fuel cells.