Comment from Takashi KAMEI

1. Executive Summary & Design Philosophy This response introduces UNOMI, an ultra-compact, loop-free molten salt micro-reactor with a thermal output of 10 MWth (~3–4 MWe equivalent). Engineered specifically for high-reliability marine propulsion, floating nuclear power plants (FNPPs), and portside microgrids, UNOMI fundamentally departs from conventional SMR architectures by eliminating primary coolant loops and dedicated primary heat exchangers. 2. Core Technical Specifications Thermal Output: 10 MWth (~3–4 MWe / ~4,000–5,000 hp equivalent) Reactor Architecture: Loop-Free, Surface-Heat-Removal Molten Salt Reactor (MSR) Moderator / Core Design: Graphite-moderated thermal-neutron core with internal fuel salt channels Coolant / Fuel Flow: Upward flow through core fuel channels, downward recirculation via outer gap Primary Heat Exchanger: None (Eliminated; direct vessel-surface heat removal) Safety Features: Inherent passive decay heat removal, low-pressure operation, zero LOCA risk 3. Key Advantages for Marine & System-Centric Integration A. Radical Simplification & Space Optimization: By completely removing primary heat exchangers and external coolant loops, UNOMI achieves an extraordinary power density and ultra-compact footprint. This allows seamless "Plug-and-Play" integration into ship hulls without necessitating radical redesigns of naval architecture. B. Inherent Safety & Marine Survivability: UNOMI operates at ambient/low pressures with liquid fuel, eliminating high-pressure steam explosion hazards and Large-Break Loss-of-Coolant Accidents (LB-LOCA). In extreme events—such as total station blackout (SBO), severe ship inclination, or capsizing—the surface-heat-removal system continuously sheds decay heat via natural passive heat sinks without relying on active pumps or external power. C. Commercial Viability & Fleet Scalability: Modular Scalability: While a single 10 MWth unit serves medium cargo vessels or auxiliary port power, multi-module configurations (e.g., 4–6 units for 40–60 MWth) provide redundant power for large commercial vessels. Cost & Maintainability: Eliminating complex primary piping and mechanical pumps reduces capital expenditure (CAPEX), lowers maintenance downtime (OPEX), and minimizes shipboard operational complexity. 4. Conclusion & Value Proposition The UNOMI micro-MSR directly fulfills the U.S. government’s vision for a "system-centric, commercially viable" marine reactor. Its ultra-simple, surface-cooled architecture provides an ideal balance of passive safety, compact integration, and economic feasibility for the future of decarbonized maritime transport.