A parametric design study of InGaAs micro-thermophotovoltaic cells coupled with various emitters at near and far spacing

摘要

A design study was conducted to determine the effect of various parameters on the performance of InGaAs thermophotovoltaic devices. The electrical power output density of the device, and the device efficiency were analyzed by considering different emitter temperatures and materials, various receiver band gap levels, and a range of gap spacings between emitter and receiver. The far spacing model, or spacing of magnitude much greater than the wavelength of the emitted radiation, was based on classical radiative heat transfer equations and standard photovoltaic cell equations. The close spacing model, or spacing with a magnitude on the order of magnitude of the wavelength of the emitted radiation, was based on the fluctuation-dissipation theorem whereby the energy is transmitted by evanescent waves between the emitter and receiver. The analytical models used realistic property values for both the receiver and the emitter, and the results show the superiority of tungsten and rhenium as emitters for the far spacing case. At close spacing, silicon carbide exceeds the performance of the refractory metals down to the spacing limited by current technology. However, if spacing control technology advances and smaller gaps become feasible, rhenium emitter devices could provide a significant increase in power density, and with similar efficiencies as the far spacing case.