PV Modules

The importance of rapid and accurate measurement of the electrical power output and related characteristics of photovoltaic (PV) modules or panels concluding the manufacturing process cannot be overemphasized. Even though these modules will likely be deployed under a variety of outdoor solar illumination conditions, they must be tested under a set of standard conditions to assure consistency of results demanded by both the manufacturer and the customer. The ability to provide a measurement tool for this critical manufacturing step that possesses the proper specifications and qualities, ranging from spectral accuracy to ease-of-use, is imperative.

Design and performance qualification testing of PV modules consists of a set of well-defined accelerated stress tests with strict pass/fail criteria. ASU-PTL is an ISO 17025-accredited testing laboratory and has been providing photovoltaic testing services since 1992. This paper presents a failure analysis on the design qualification testing of both crystalline silicon (c-Si) and thin-film technologies for two consecutive periods: 1997-2005 and 2005-2007. In the first period, the industry was growing at a slower rate with traditional manufacturers, with qualification testing of c-Si technologies being primarily conducted per Edition 1 of the IEC 61215 standard. In the second period, the industry was growing at an explosive rate with new manufacturers joining the traditional manufacturers, while qualification testing of c-Si was primarily conducted per Edition 2 of IEC 61215. Similar failure analysis according to IEC 61646 has also been carried out for thin-film technologies. The failure analysis of the test results presented in this paper indicates a large increase in the failure rates for both c-Si and thin-film technologies during the period of 2005-2007.