GSES recently released a technical paper on Potential Induced Degradation (PID). The abstract from this paper is below; to read the full article, visit the Resources and Information page.
Potential Induced Degradation
Causes, Effects and Possible Solutions
Potential Induced Degradation (PID) is a process that occurs in photovoltaic (PV) cells when the system has a negative potential relative to the ground. As a result, the PV module’s efficiency decreases over time. Although PID is a relatively new concept and is not widely understood, techniques already exist to minimise its undesirable effects. The prevention of these adverse effects mainly involves changes in the material used and the system design. However, for systems already affected by PID or for those susceptible to it, a device has been developed that reverses the polarity of the array, forcing the negative charge out of the module.
This report provides background information on PID, including how this degradation process develops, the conditions that make PV systems prone to it, its effects and the methods to correct or prevent it.