A novel methodology to estimate the cell temperature of PVT modules: test with experimental data, prospects and limits

Abstract

The efficient use and understanding of photovoltaic thermal modules require accurately evaluating the temperature of their photovoltaic cells. But due to their specific composition, measuring this temperature directly is usually very complicated, if not impossible in practice. In this article, we present an original methodology to estimate the temperature of the cells of a PVT module. In order to do this, we simultaneously conduct experiments on both PVT and PV modules equipped with identical PV cells, and compare their electrical performance. The temperature of the PV module's back side is measured and used to estimate the temperature of the PV cells. The latter is then combined with the electrical power output difference between PV and PVT modules in order to obtain, through a specifically developed thermal model, the cell temperature of the PVT module. In addition, an experimental comparative analysis of different PVT modules is presented. The methodology and the results are promising but the experimental measurements used are subject to significant uncertainties that impact the accuracy of the estimation. The model uses an innovative approach to estimate the PV cell temperature of PVT modules, and recommendations are provided to optimize experimental data measurement accuracy in order to use this model in the best possible conditions.