Integrating fourth–generation reactors into maritime transport

This study explores the application of fourth–generation (Gen IV) nuclear reactors as propulsion systems for shipping with zero direct emissions of CO 2 . It evaluates the potential to replace fossil fuels, supporting the United Nations sustainable development goals (SDGs). Gen IV reactors offer high energy efficiency, zero greenhouse gas emissions, and extended operational autonomy without refuelling. Technologies such as very high–temperature reactors (VHTRs), small modular reactors (SMRs), and molten salt reactors (MSRs) are highlighted for their innovative safety features and fuel flexibility. Technical feasibility is assessed alongside economic aspects of nuclear propulsion, including reduced operating costs, potential revenue from carbon credits, and increased cargo capacity. Challenges include high initial costs, public resistance, and regulatory concerns. A comprehensive analysis of Gen IV nuclear reactors addresses these barriers and proposes solutions, including the adoption of advanced passive safety systems. This article demonstrates that the implementation of Gen IV reactors could contribute significantly to maritime decarbonization, ensuring environmental sustainability and economic viability. • A comparative analysis of Gen IV nuclear reactors. • Overview of nuclear regulations and class requirements across major classification societies. • Evaluation of Gen IV reactor types for different ship classes and operational profiles. • Passive safety systems and advanced fuel cycles to enhance operational safety and efficiency. • Development of nuclear propulsion addresses the growing need for maritime decarbonization.