Outdoor Implied Current–Voltage Measurements of an Individual Encapsulated Cell in a Module

The performance of solar cells influences the reliability, lifetime, cost, and safety of photovoltaic power plants. The electrical performance of these cells, as well as, their degradation rates over time, can vary between individual cells within the same photovoltaic module. Current-voltage measurements can provide detailed data on cell performance, however, it cannot be performed on individual cells in encapsulated modules. In this study, we propose a contactless and nondestructive method that is based on Suns-photoluminescence measurements to extract the current-voltage characteristics of individual solar cells under operating conditions in the field. Applications of the method to identify the extent of various degradation mechanisms, such as light-induced and potential-induced degradation, are demonstrated and discussed. The main advantages of the proposed method include its low cost, and its fast and easy applicability.