LDK Solar Co. Ltd. says its 60- and 72-cell multicrystalline modules have passed the potential-induced degradation (PID) tests performed at TUV Rheinland's and PV Lab's laboratories. In both tests, LDK modules demonstrated a reduction in performance under test conditions of less than 1%, earning a Class A rating.
PID has become a major concern, as it can significantly reduce the power output of a PV system, LDK Solar says. Inherent differences in voltage between the module framework and solar cells, as well as environmental conditions such as increased humidity and higher temperatures, can lead to degradation over the life cycle of the module, reducing the yield of a PV system.
During the tests performed by TUV Rheinland and PV Lab, a negative voltage of 1,000 V was applied to the modules at an ambient room temperature (25 degrees C) and humidity over a period of seven days. The module front was covered with aluminum foil or a constant water film to minimize the resistivity with the grounded frame.Â