Annual Degradation Rates of Recent c-Si PV Modules under Subtropical Coastal Climate Conditions

This paper shows the annual degradation rates of six types of crystalline silicon (c-Si) photovoltaic (PV) modules under subtropical coastal climate conditions based on three parameters: annual energy production, performance ratio under high and stable solar irradiance conditions, and power output measured under the standard test conditions (STC). The results indicate that the PV modules composed of p-type c-Si solar cells with aluminum back surface field (Al-BSF) tend to show the lower annual degradation rates of 0.3%/year or less, although the PV modules consisting of n-type c-Si solar cells such as silicon heterojunction (SHJ) and interdigitated back contact (IBC) tend to show the higher degradation rates from 0.5 to 1.2%/year.