Estimating the impact of defects in photovoltaic cells and panels

Abstract

This paper investigates defects in photovoltaic cells and panels which cause notable losses in output performances. Here, the focus lies on the impact of hairline cracks which result in a remarkable drop of the available output current and, thus, the available output power. Firstly, samples were characterised with the help of synchronized thermography (ST) in order to localise and analyse the defects. Secondly, samples were measured with the help of electrical verification to obtain the characteristic I-V (Current-Voltage) curve. Finally, the geometric area of PV cells was calculated which corresponds to the effective area for energy production due to the presence of a defect. Results show the correlation between the available power of PV cells with temperature variations in IR-emissions. Proposed methods are capable of detecting defects in PV cells and quantise the impact on output performances.