Output power behavior of passivated emitter and rear cell photovoltaic modules during early installation stage: influence of light-induced degradation

The conversion efficiency of passivated emitter and rear cell (PERC) photovoltaic (PV) modules decreases via light-induced degradation (LID). In this study, two models of commercial PERC PV modules were employed. These modules were exposed outdoors until the accumulated solar irradiation reached 687 kW m(-2) to investigate their power generation behavior during the early installation stage. The maximum output power (P-max) finally decreased by 1.52% in one model and by 4.29% in the other model. P-max of the latter model increased after LID owing to light-induced regeneration under open-circuit conditions. However, power generation in the array of the latter model connected to an electrical power grid was not changed after LID and no recovery was observed. It was found that the extent of degradation and the behavior differ depending on not only the difference in models but also the circuit conditions during exposure. (C) 2019 The Japan Society of Applied Physics