Thermodynamic Assessment of a Compact 3D-Printed Reactor-Heat Exchanger for 1kW Ammonia-Solid Oxide Fuel Cell Power Systems

Ammonia is a promising hydrogen carrier for solid oxide fuel cells (SOFCs) due to its high hydrogen density, carbon-free nature, ease of storage and transport, and its ability to be efficiently decomposed or internally reformed at high temperatures for effective energy conversion. Nevertheless, there is a direct use of ammonia, which needs to be well thermally controlled and with highly efficient catalytic breakdown in order to enable efficient on-site hydrogen generation. This paper examines the thermodynamic feasibility of a new 3D-printed integrated heat exchanger and catalytic reactor that can utilise high-grade waste heat from SOFC exhaust for catalytic processes. The suggested design increases the fuel consumption, thermal efficiency, and the system life by decreasing thermal stresses. Ammonia is catalytically decomposed in the reactor into hydrogen and nitrogen, then it undergoes electrochemical conversion, which uses both anode and cathode exhaust gases as heat sources. This was discovered with the base SOFC system registering a power output of 1079.5 W at an operating temperature of 1023 K using a fuel utilization rate of 85% with an efficiency of 48.8%. The use of an in-built heat recovery catalytic reactor also increased the overall system efficiency to about 72%. The findings expressed in this work carry an adequate basis on which scalable, carbon-free, ammonia-fed SOFC-based energy solution can be developed to be used in maritime transport, data centers, and decentralized/off-grid energy solutions. • A novel ammonia-fed SOFC integrates a 3D- printed heat exchanger and reactor. • SOFC exhaust heat enables ammonia preheating and catalytic decomposition. • The system delivers 1 kW power with 48.8% electrical efficiency at 750°C. • Integrated heat recovery raises overall system efficiency to 72%. • The concept supports scalable, carbon-free power for transport and off-grid use.