Thermal models for mono/bifacial modules in ground/floating photovoltaic systems: A review

Abstract

Since the world's policy tends to rely on solar energy to meet energy needs, photovoltaics are considered a crucial asset that requires continuous monitoring. Several installation solutions, including different PV technologies, created challenges in providing a reliable evaluation to depend on. Thermal modeling is essential to predict the cell temperature that is utilized in anticipating the system's electrical performance, as in most commercial software. Hence, this work provides an overview of the most used thermal models for installation solutions (free-standing, roof-mounted, floating, etc.) utilizing both mono and bifacial module technology. The provided analysis is focused on evaluating the different responses of the thermal models that can be used for the same configuration and technology. A sensitive comparative analysis of the various thermal models is provided to assess their response to the climatic parameters as an input to the thermal model. The analysis revealed that for monofacial thermal models, Ross models underestimate the cell temperature at any radiation intensity, while the Faiman model using PVsyst coefficients generates the highest overestimated cell temperature among the examined models. It can be seen that the effect of wind speed reduces for a velocity higher than 10 m/s. As for the bifacial PV module, it can be noticed that the Sandia model using Bifacial optimized coefficients is very sensitive to the back surface radiation as it tends to overestimate relative to the Faiman model. Furthermore, floating PV thermal models are significantly affected by the heat transfer coefficient that usually produces a lower cell temperature.