Experimental characterization of direct ammonia solid oxide fuel cell for stationary application

Solid oxide fuel cells (SOFCs) are power generation devices that use the chemical energy of hydrogen or other fuels to cleanly and efficiently produce electricity. The aim of this thesis, in particular, is to experimentally investigate a SOFC stack fed by ammonia. Several tests have been carried out...

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Detalles Bibliográficos
Autor: Armario Bernabé, Òscar
Tipo de recurso: tesis de maestría
Fecha de publicación:2025
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/429580
Acceso en línea:https://hdl.handle.net/2117/429580
Access Level:acceso abierto
Palabra clave:Solid oxide fuel cells
Clean energy
Solid oxide fuel cell
Ammonia
Ammonia cracking
Hydrogen
Area specific resistance
Anode gas recirculation
Piles de combustible d'òxid sòlid
Energia neta
Àrees temàtiques de la UPC::Energies::Eficiència energètica
Àrees temàtiques de la UPC::Energies::Gestió de l'energia
Descripción
Sumario:Solid oxide fuel cells (SOFCs) are power generation devices that use the chemical energy of hydrogen or other fuels to cleanly and efficiently produce electricity. The aim of this thesis, in particular, is to experimentally investigate a SOFC stack fed by ammonia. Several tests have been carried out at temperatures from 690 to 750 °C to compare the device performance using ammonia as inlet fuel against that using hydrogen or a stoichiometric mixture of hydrogen and nitrogen (3:1 molar basis). The obtained polarization curves showed similar performances for hydrogen and the mixture, while that of ammonia presents a lower performance and deviates from the rest as temperature increases. The electrical efficiency ranges from 45.0 to 51.4% at full load, with ammonia being the most efficient fuel. If an ideal case where external cracking does not have any additional energy consumption is considered, these values can reach up to 52.3%. Finally, the anode gas recirculation has been simulated with different hydrogen-nitrogen mixtures to analyze its effect on the stack performance and the electrical efficiency. Performance decreases as the recirculation factor increases, while the electrical efficiency ranges from 29.4 to 66.7% in the studied cases, showing an exponential increase at partial load. If the previous ideal case is again considered, these values can reach up to 75.8%, concluding that the values that could be reached with ammonia are in this same order of magnitude. The results of this thesis confirm the feasibility of ammonia as inlet fuel for SOFCs, showing higher electrical efficiencies than those of hydrogen at the expense of lowering the performance.