Performance degradation of commercial Ga‐doped passivated emitter and rear cell solar modules in the field

Abstract

AbstractGallium‐doped passivated emitter and rear cells (PERCs) showed great promise for future advanced highly efficient solar cells. However, there is a lack of information available regarding the field degradation of gallium‐doped PERC solar modules. In this work, the field degradation of gallium‐doped PERC solar modules is investigated and compared with the field degradation of stabilized boron‐doped PERC solar modules. It is remarkable that the peak power degradation curves of the gallium‐doped PERC solar modules present two degradation stages which might be attributed to synthetical results of light‐induced degradation (LID) and light and elevated temperature‐induced degradation (LeTID). The extents of degradation for the gallium‐doped PERC solar modules are smaller than that of the stabilized boron‐doped PERC solar modules. The LID characteristic of the gallium‐doped PERC solar modules is caused by the presence of residual boron in Ga‐doped Cz‐Si wafers which has been demonstrated by the results of inductively coupled plasma‐mass spectrometry. Moreover, a comparative study of daily yield for gallium‐ and boron‐doped PERC photovoltaic arrays is carried out. It was found that the gallium‐doped photovoltaic array has a higher energy yield and shows a better performance ratio than the boron‐doped photovoltaic array. The reason is that the performance degradation and its induced mismatch loss of gallium‐doped solar modules in the field are smaller than that of the boron‐doped solar modules.