Study on the performance of a novel photovoltaic thermoelectric system based on optical filters and multi-stage phase change materials

In recent years, with the international community's increasing emphasis on clean energy, solar photovoltaic (PV) power generation has also become the focus of scholars' research. In order to solve the problems of low power generation utilization and short lifetime of PV modules in a standard PV system, a spectrally enhanced multi-stage thermoelectric conversion (SM-TEC) integrated system is proposed in this study. The system innovatively integrates a “sandwich-type” multi-stage phase change structure and water-based optical filters into a photovoltaic-thermoelectric system. Through a combination of simulation and numerical calculations, the performance indicators are analyzed in comparison between the SM-TEC integrated system and the standard PV system and the photovoltaic-phase change system. The results show that the SM-TEC integrated system has a high potential for PV panel temperature control, photovoltaic conversion efficiency, and heat storage. In addition, the effect of the working fluid flow rate on the system performance is explored. It is found that when the working fluid flow rate is 1.979 × 10−7 m3/s, the peak temperature of the PV panel is 334.64 K and the peak electrical efficiency reaches 23.88 %; when the flow rates are 1.979 × 10−7 m3/s, 2.545 × 10−7 m3/s, 3.110 × 10−7 m3/s, 3.676 × 10−7 m3/s, the peak temperatures of the PV panel are 333.11 K, 331.83 K, 330.80 K, and 329.97 K. It can be found that the temperature control performance of the PV panel shows an enhanced trend with the increase of the working fluid flow rate.