Comparison of efficiency degradation in polycrystalline-Si and CdTe thin-film PV modules via accelerated lifecycle testing

Research output: Chapter in Book/Report/Conference proceedingConference contribution

2 Scopus citations


Thin-film solar cells normally have the shortest energy payback time due to their simpler mass-production process compared to polycrystalline-Si photovoltaic (PV) modules, despite the fact that crystalline-Si-based technology typically has a longer total lifetime and a higher initial power conversion efficiency. For both types of modules, significant aging occurs during the first two years of usage with slower long-Term aging over the module lifetime. The PV lifetime and the return-on-investment for local PV system installations rely on long-Term device performance. Understanding the efficiency degradation behavior under a given set of environmental conditions is, therefore, a primary goal for experimental research and economic analysis. In the present work, in-situ measurements of key electrical characteristics (J, V, Pmax, etc.) in polycrystalline-Si and CdTe thin-film PV modules have been analyzed. The modules were subjected to identical environmental conditions, representative of southern Arizona, in a full-scale, industrial-standard, environmental degradation chamber, equipped with a single-sun irradiance source, temperature, and humidity controls, and operating an accelerated lifecycle test (ALT) sequence. Initial results highlight differences in module performance with environmental conditions, including temperature de-rating effects, for the two technologies. Notably, the thin-film CdTe PV module was shown to be approximately 15% less sensitive to ambient temperature variation. After exposure to a seven-month equivalent compressed night-day weather cycling regimen the efficiency degradation rates of both PV technology types were obtained and will be discussed.

Original languageEnglish (US)
Title of host publicationReliability of Photovoltaic Cells, Modules, Components, and Systems X
ISBN (Electronic)9781510611979
StatePublished - Jan 1 2017
EventReliability of Photovoltaic Cells, Modules, Components, and Systems X 2017 - San Diego, United States
Duration: Aug 6 2017Aug 7 2017


OtherReliability of Photovoltaic Cells, Modules, Components, and Systems X 2017
CountryUnited States
CitySan Diego



  • Accelerated lifecycle testing
  • Degradation
  • Environmental chamber
  • Photovoltaic
  • Polycrystalline
  • Thin film

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Computer Science Applications
  • Applied Mathematics
  • Electrical and Electronic Engineering

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