Energy and exergy analysis of photovoltaic thermal collectors: Comprehensive investigation of operating parameters in different dynamic models

Abstract

The comparative analysis of a transient two-dimensional model and a lumped parameter model for photovoltaic thermal (PV/T) devices were presented, focusing on the energy and exergy performance under different operating conditions. The lumped parameter model involves the effective heat capacity for solar collectors and a zero-dimensional dynamic model for the calculation of the heat transfer coefficient. The study established both models and examines their differences in temperature distribution and computational results. Results indicate that the lumped parameter model, considering computational efficiency and simplified processes, serves as an effective tool for evaluating PV/T device performance, with a maximum relative error of 3.51 % in calculated results. Additionally, the impact of irradiance and flow rate on energy efficiency and exergy efficiency was investigated. After mass flow reaching 0.02 kg/m2/s, the thermal efficiency is 50.15 %, reaching a stable state. The research highlights the significant influence of operating conditions on the overall performance of PV/T collectors. The exergetic flow distribution of PV/T collector was obtained, with an overall exergy efficiency of 13.13%–14.96 % in different operation, and the research further analyzed the causes of exergy loss of PV/T collectors and possible improvement directions. The findings contribute to advancing the understanding and optimization of PV/T systems for enhanced energy conversion and exergy utilization.