DEGRADATION ANALYSIS OF DIFFERENT PV MODULES AFTER PROLONGED FIELD OPERATION

摘要

The quality of a photovoltaic module is determined by the manufacturing process and the quality policy of themanufacturer, which is generally tested and evaluated as per international standards issued by various organizations like theIEC. These tests are commonly referred to as design qualification and type-approval tests, and are designed to assess the PVmodule’s reliability and quality on the basis of standardized criteria under conditions known to have contributed to commondegradation mechanisms. However, these tests are not sufficient for estimating the module lifetime as it has been observedthat even the qualified modules have failed or degraded more than expected, in field conditions[1]. Hence, it is critical tostudy the phenomenon of degradation in order to assess the module’s performance in the actual operating environment andfor creation of better module designs. In this paper we present the findings and our analysis of the single-crystalline andthin-film modules of five different commercial designs produced by ten manufacturers. These modules were deployed forabout 10 years in the test beds at the Solar Energy Centre(SEC), Gurgaon, India. It has been observed from experimentalresults that modules employing Cadmium Telluride (CdTe) and mono-crystalline technologies are more resilient todegradation than the amorphous-silicon modules with average degradation of 18.23% and 12.25% respectively, whereas foramorphous silicon double junction modules showed degradation of 27.24%.For the triple junction and CIS modules,observed degradation is in the range of 35% and 36% from their initial values respectively.