Optimizing photovoltaic-thermal systems: a comprehensive indoor experimental investigation

Photovoltaic thermal collector (PVT) is an innovative solar technology that integrates photovoltaic (PV) and solar thermal systems to simultaneously generate electricity and heat. This study explores the performance of a PVT system by examining the relationships between solar radiation, water mass flow rates, outlet water temperatures, and electrical output voltage. Experimental results demonstrated that outlet water temperature increased by 12 °C on average as solar radiation rose from 200 to 900 W/m2, highlighting the proportional relationship between solar radiation and thermal energy absorption. Conversely, increasing water mass flow rates from 0.005 to 0.016 kg/s reduced the outlet water temperature by approximately 4.8 °C, showcasing the critical role of flow rate optimization in enhancing heat transfer efficiency. In terms of electrical performance, the PVT system’s output voltage increased by 5% as solar radiation rose from 200 to 900 W/m2. Additionally, doubling the mass flow rate led to a 10% increase in voltage, underscoring the importance of water flow optimization in improving electrical output. The research method demonstrates a significant advantage through the methodical combination of controlled experimental setups with comparative theoretical analysis, providing a deeper understanding of the practical and theoretical performance of PVT systems. Validation of experimental findings with theoretical results not only confirmed system performance trends but also emphasized the role of practical experimentation in refining and advancing theoretical models, ultimately contributing to enhanced PVT system efficiency.