Experimental demonstration of a novel approach to increase power conversion potential of a hydrocarbon fuelled, portable, thermophotovoltaic system

A novel, compact mesoscale thermophotovoltaic (TPV) power generating system using a combination of porous media combustion and a simple band-pass filtering method has been proposed and experimentally studied. The novelty in this work is the idea of harvesting the heat produced in the microcombustor via the silicon carbide (SiC) porous media which becomes an effective radiator owing to its high emissivity. This is then combined with wafers that have a high optical transmissivity in the part of the spectrum that is useful for power conversion using the TPV system. In this work, we utilised two combustor wafers (silicon and quartz) with suitable thermal and optical properties. Quartz having a high transmissivity of 0.9 compared to silicon (<0.6) proved to be superior in performance when combined with the porous media combustion for TPV power generation. To further illustrate the combination of effects, we also performed experiments in which porous media was not inserted in the combustor and the radiation was effectively from the hot combustor walls. In this case, silicon which has a higher emissivity than the quartz performs better. Overall the TPV power generation was SiC + quartz > SiC + Si > pure Si walls > pure quartz walls.