Solar cell/module degradation and failure diagnostics

Solar cell/module degradation and failure diagnostics are reviewed. Cell and packaging failure are distinguished. Failure relevant to photovoltaics(PV) is caused by and can be accelerated with each or combination of each of the following stresses: temperature, voltage, moisture, current, and thermal cycling. Failure mechanisms for the different module technologies are summarized. Diagnostic tools for locating the affected area within a large-area module are pointed out along with the importance of interpretation of the visual appearance of the different damage mechanisms.