Sensitivity analysis of a solar thermophotovoltaic system with silicon thermal storage

Transient simulations for solar thermophotovoltaic (STPV) systems utilizing silicon as phase change material (PCM) and Er3Al5O12 as selective emitter with Ge cell are presented. A sensitivity analysis was carried out in order to study the effect on the efficiency of the STPV system of the PCM size, solar irradiance and location of the selective emitter with respect to the receiver cavity. The results show that higher efficiencies can be achieved by placing the selective emitter and the PV cell close to the receiver cavity. Also, the optimum size of the PCM depends on the amount of incident solar radiation and the storage capacity required. Furthermore, increasing the solar flux to very high value or reduce it to very small value reduces the efficiency of the overall system.