Experimental analysis and optimization of a concentrated thermo-photovoltaic collector with bi-facial receiver

In this study, a concentrated thermo-photovoltaic collector is examined experimentally and numerically, while it was geometrically optimized. The main objective is the collector's thermal performance evaluation and optical optimization for operation in Greece. Experiments were conducted in Athens, Greece, from July 10th to 17th, 2023, investigating the thermal operation of the collector in a temperature range of approximately 40-80 degrees C. The collector's slope was set to 12.3 degrees degrees for maximum solar irradiance utilization during the specified dates, considering south orientation. A numerical model was created using SolidWorks Flow Simulation and COMSOL Multiphysics, The model was validated with the experimental data, achieving mean deviation less than 6.5 % and a maximum deviation of 9.6 %. Various geometries were optically examined using Tonatiuh software. By applying a performance evaluation criterion, a new design is proposed and compared to the initial design across four different months, considering constant tilt angle. A maximum thermal efficiency of 49.19% at the lower inlet temperature was found experimentally. The temperature of the PV cells was found to be highest where the solar rays are concentrated. Shape optimization revealed significant enhancements in optical efficiency, particularly at negative incident angles. The new geometry showed substantial improvement, with enhancements exceeding 20 % considering daily operation.