Employing Taguchi method to optimize the performance of a microscale combined heat and power system with Stirling engine and thermophotovoltaic array

This study proposes a biosyngas-fueled power system, which is a fusion between a micro-thermophotovoltaic (micro-TPV) system and a Stirling engine. The combustor in the micro-TPV is a coaxial tube made of plat-inum. Biosyngas was simulated using different compositions of H2 and CO mixture. The H2/CO/air mixture was delivered to the inner channel of the micro-TPV combustor, while the CH4/air mixture was delivered to the outer channel. This study realized a micro-CHP system with a combustion-driven TPV cell array, and a Stirling engine -driven power generation system. This micro-CHP system harvests energy generated through thermal radiation from the reactor's surface as well as thermal energy from hot flue gas. The results indicate that the overall ef-ficiency of the biosyngas-fueled micro-CHP system was strongly dependent on fuel composition, fuel/air ratio, and flowrate mixture. Thus, Taguchi method was employed to find optimal operative conditions; the highest efficiency was achieved under a biosyngas composition of 80% CO and 20% H2, with a flow velocity of 6 ms-1, and an equivalence ratio of 1.2, and its corresponding overall efficiency reached 43%, incorporating 0.84 W electricity output by TPV cell array, 3.25 W electricity output by Striling engine-driven power generation system, and 325.5 W of water energy gained.