Systematic review of ferry decarbonization in the maritime sector

Abstract The shipping industry is a cornerstone of global trade and a contributor to greenhouse gas (GHG) emissions. Within this sector, ferries play a crucial role in connecting communities and facilitating regional trade. However, smaller ferries—particularly those under 5000 gross tonnage (GT) engaged in short sea shipping—often evade stringent regulation despite their environmental impact. This paper conducts a five-stage systematic literature review following the PRISMA-method, systematically identifying and analysing 61 peer-reviewed publications on ferry decarbonization published over the past 13 years. The study highlights a peak in research in the year 2025 and identifies three key research areas: technological innovation, regulatory frameworks and operational strategies coupled with economic considerations. It further identifies critical gaps, including the need for coordinated policy efforts, the integration of renewable energy sources, and adaptive strategies to balance environmental and economic objectives. The paper contributes to the academic discourse by offering a structured and transparent synthesis of this under-researched topic while providing practical implications for the industry stakeholders, bridging the gap between policy goals and real-world outcomes, and outlining future research directions for maritime decarbonization.