Daylight electroluminescence inspection of PV panels on-site vs. Traditional EL inspection with Silicon cameras

Abstract

This paper presents a comparative study of electroluminescence (EL) imaging of silicon photovoltaic (PV) panels in three currently operating PV plants. EL images were acquired using two methods: in a darkroom with a silicon sensor reflex camera after dismantling the panels; and during daylight without dismantling the panels using an InGaAs sensor camera (dEL). The results demonstrate that dEL can detect the same important defects in the PV panels while being not only less costly in terms of time and money but also able to prevent the production of new defects resulting from disassembly, transportation and reassembly of the modules. This way, dEL provides a more efficient and reliable procedure for quality control and maintenance.