UV Degradation in Backsheets: A Ray-Tracing Irradiance Simulation Approach

Research output: NRELPoster


Around 90% of current photovoltaic (PV) modules are less than ten years old. New PV technologies and materials are deployed without documented durability and performance histories. Accelerated testing attempts to capture degradation modes but can produce false results with such rapid deployment of new materials. Current testing assumes UV dosage on the rear of a module to be 10% of that incident on the front. We present a method to quantify degradation on PV backsheets in the field. We aim to evaluate if current acceleration factors for UV damage in chambers are properly estimating degradation for different PV site installations. The method leverages bifacial_radiance to ray-trace and evaluate irradiance on the front and the rear of the modules. Then an equation to estimate the relative degradation is proposed.
Original languageAmerican English
StatePublished - 2022

Publication series

NamePresented at the Photovoltaic Reliability Workshop (PVRW), 21-25 February 2022

NREL Publication Number

  • NREL/PO-5K00-82144


  • accelerated testing
  • backsheets
  • ray trace
  • UV degradation


Dive into the research topics of 'UV Degradation in Backsheets: A Ray-Tracing Irradiance Simulation Approach'. Together they form a unique fingerprint.

Cite this