Theoretical and experimental investigation of a photovoltaic/thermal panel partially equipped with thermoelectric generator under unstable operating conditions

Summary The efficiency of photovoltaic cell is highly temperature‐dependent; therefore, the performance of these solar panels would be increased by decreasing the temperature. In this research, a novel integration of coupling thermal photovoltaic panels with thermoelectric generator module (PVT‐TEG) is investigated for possible application in reducing cell temperature in order to increase output electrical power, thermal efficiency, and overall efficiency of the integrated PVT‐TEG system. Initially, component validation is performed by experimental data with equipment in the energy laboratory for high reliability. In the hybrid system (PVT‐TEG), one‐third of a monocrystalline PV panel backside was equipped with thermoelectric generators (TEG), while aluminum water blocks were attached to the cold side of TEGs for cooling aim, then tested and compared with a simple panel at the same environment condition (Shahrood city in Iran) from August until September 2020. In this study, the influence of water velocity and its temperature are studied simultaneously. In addition, mathematical modeling is based on thermal resistance, whereas the impact of the thermal resistance of adjacent layers, TEGs, and the upper heat loss thermal resistance on the PVT‐TEG system and simple panel properties are investigated, respectively. Experimental and theoretical data are validated with obtained results from MATLAB and showed acceptable deviation error with less than 18%. The electricity generated in the PVT‐TEG panel is 8.5% more than a simple panel. TEG power generation has a small share of total power generation, so economic assessment is essential for industrial production. Finally, parametric analysis in PVT‐TEG estimates 70% higher total efficiency compared with conventional simple panel.