Modeling and experimental investigations of high-efficiency and cost-competitiveness of solid oxide fuel cell-gas turbine system with recovering waste heat technology from biomass-based hydrogen and ammonia energy conversion

A high-efficiency hybrid power generation from biomass-based hydrogen and ammonia solid oxide fuel cell (SOFC)-gas turbine (GT) with recovering waste heat from exhaust gas was developed to determine the most feasible configuration, and the energy efficiency and economic performance of the system were analyzed. The effects of temperature, pressure, fuel utilization factor and pressure ratio were determined and excellent agreements were found for the experimental and simulation data on H2 production from biomass gasification, NH3 decomposition, and SOFC using NH3 or H2 fuels to power generation, confirming the model's capability to predict the performance of the system accurately. The SOFC-GT integrated with waste heat recovery improved system efficiency and cost competitiveness. Compared with the NH3-GT and NH3-SOFC-GT, the integrated system of NH3-H2-SOFC-GT presented the highest efficiency of about 66 %, and the highest exergy loss occurred in H2 production from biomass gasification, followed by NH3 synthesis. Power generation contributions were measured at 22.48%, 31.76% and 32.42%, respectively for NH3-GT, NH3-SOFC-GT, and NH3-H2-SOFC-GT. In terms of economic competitiveness, they were ranked as follows: the NH3-H2-SOFC-GT > the NH3-SOFC-GT > the NH3-GT. This study highlights the potential of an integrated NH3-H2-SOFC-GT system for energy efficient and economically feasible power generation.