Parametric characteristics and optimization of a near-field thermophotovoltaic system considering cooling consumption

Abstract

Near-field thermophotovoltaic (NF-TPV) system based on the photon tunneling effect can effectively increase the output power, which has shown great application potential in solar energy utilization. In order to evaluate the performance of NF-TPV system more reasonably, this study established an optimization model of NF-TPV combined with a water-cooling system to better reflect the physical process of system running. Taking into account the energy consumption of cell water cooling, the performance of NF-TPV system with tungsten emitter and InAs cell was analyzed and optimized through numerical simulation. The influence of operating parameters such as emitter and cell temperatures, applied voltage and vacuum gap on the system performance was investigated. It is found that the operating parameters of NF-TPV combined with water cooling system have their optimal ranges, which can ensure the high efficiency and output power of the system simultaneously. When NF-TPV is applied in waste heat recovery, the cooling energy consumption could be ignored. In solar energy conversion, the emitter temperature should be kept as high as possible, and the cooling energy consumption must be considered when the emitter temperature is above 1000 K. If fuel combustion is used as NF-TPV heat source, the emitter temperature should not exceed 1500 K. This study provides guidance for the practical application of NF-TPV systems.