Potential induced degradation (PID) is one of the main causes if a solar power plant’s performance diminishes over the course of its service life. Several solar manufacturers have now partnered up with renowned German testing institutes to launch a new initiative to prepare standard module tests for this phenomenon, which has been the subject of a large number of recent investigations. The objective is to enable consumers to recognize PID-resistant modules.
Solar energy companies SOLON, Schott Solar and Q-Cells, along with the Fraunhofer Institute for Solar Energy Systems ISE, the Photovoltaik-Institut Berlin (PI-Berlin), TÜV Rheinland and the VDE, the Association for Electrical, Electronic & Information Technologies, have developed a test for this purpose, which is easy to conduct and allows a solar module’s PID resistance to be tested. Electrical leakage current, which can flow between a solar power plant’s components, causes the power loss through PID. Instead of producing electricity, the cells short-circuit themselves.
During the test, PID-stabilized series production modules from the participating companies as well as modules from other brand manufacturers were subjected to the maximum system voltage of 1,000 V at a temperature of 25 degrees for seven days. To achieve exact comparative values, all modules were grounded and covered with aluminium foil or a continuous water film. The relevance of the test conditions was controlled using prepared test modules that SOLON had previously developed for all testing institutes. If a module lost less than five percent of its power during the test, it was considered PID-resistant within this context.
