Spectrally Controlled Thermal Radiation Based on Surface Microstructures for High-efficiency Solar Thermophotovoltaic System

Thermophotovoltaic (TPV) system is expected to generate electrical power from various heat sources. One of the key devices of TPV system is spectrally control thermal emitters. The performance is not sufficient to achieve high efficient TPV systems. In this study, we developed new type spectral selective emitters with closed-end surface microcavity array. The simulated spectral thermal radiation band width is only 70 nm and Q-value=26.4. This Q-value is 5 times larger than the conventional open-end microcavity emitters. The design of Solar-TPV system which is driven by concentrated solar energy using refractory metal emitters with multi-layer coating. The estimated system efficiency and electric power density using the experimentally obtained spectral property of the selective emitters is 16.6% and 2.9W/cm2, respectively.