Nuclear lead-cooled fast reactor (LFR) for naval propulsion and shore connection: an energy, economic and environmental analysis

This paper explores the integration of IV generation small modular reactors (SMRs) into maritime vessels as a viable and sustainable alternative to conventional fossil-based propulsion systems. In particular, it focuses on a nuclear lead-cooled fast reactor (LFR) fed by mixed oxide (MOX) fuel and coupled with a Helium Brayton cycle system featuring regeneration and reheating. The proposed energy system is modelled and implemented within a novel dynamic simulation tool designed to assess the energy, economic, and environmental performance of the considered power plant under various boundary conditions. To demonstrate both the applicability of the of LFR power system for naval use and the capability of the simulation tool, a new case study is presented. It involves a sample containership in which the conventional HFO diesel engine is replaced with the modelled LFR power plant. A sample cruise based on real-time online data is used to assess the system behaviour under realistic, dynamically changing maritime conditions. In addition, the study investigates a novel ship-to-shore connection concept, in which electricity generated onboard by the nuclear power system is supplied to onshore electricity grids during port stays. Simulation results show that deploying compact LFR systems on ships could effectively eliminate fossil fuel emissions during operation. Specifically, results show that the avoided CO2 emissions are 25.0 kt/y during navigation; additional 17.1 kt/y of avoided emission can be obtained during port stays (including electricity sold to onshore grid); annual electricity revenues from the ship-to-shore power supply is 2.13 M€/y; the minimum payback is 6.4 years (including system maintenance costs, onshore carbon tax, and ETS; whilst disregarding dispatchment tariffs).