Photovoltaic Degradation

The Critical Failure Modes and Degradation Mechanisms (Multiscale) project through Case School of Engineering’s Solar Durability and Lifetime Extension (SDLE) Research Center is detailed below.

Project Overview

In this project, the University of Central Florida (UCF), the Florida Solar Energy Center (FSEC), Case Western Reserve University (CWRU), Tau Science, and BrightSpot Automation will apply multiscale characterization methods to field exposed photovoltaic modules to link observed performance degradation to specific loss mechanisms (i.e., optical, recombination, resistive) and, ultimately, to root causes (i.e., changes in chemistry and/or microstructure). This research will be carried out on a very large and diverse population of modules to ensure statistical relevance, providing a deeper understanding of reliability and durability defects common to field exposed modules. This includes modules located at UCF main campus, FSEC, and CWRU, as well as systems located at external partner sites, including NextEra, Southern Company, Orlando Utilities Commission, and esaSolar (see attached letters of support). The team will use the information and insights gained, along with feedback from a technical advisory board, to guide future PV cell, module, and system technology developments.

To get the maximum amount of information on the largest possible population of modules in a time efficient and cost-effective manner, a tiered down-selection process will be used (Figure 1). This will begin with large-scale analysis of time-series power (PMP) and current-voltage (I-V) data, followed by the application of traditional high throughput infrared (IR) imaging, a new high throughput UV fluorescence (UVF) imaging technique, and a novel high resolution, non-contact combined photoluminescence (PL), electroluminescence (EL) imaging, and UVF imaging technique. Analysis of the time-series data and field-based imaging will be used to select modules for further characterization in a controlled laboratory setting. This analysis will then be used to make assessments on the most likely root cause of the observed failure modes and degradation mechanisms. Finally, from those modules, individual regions of interest (e.g., with/without observed defect) will be cored out for targeted materials characterization (e.g., SEM, EDS, XPS, Fourier transform IR spectroscopy) to provide final confirmation of the root cause.

Members and Collaborators

  • Kristopher Davis (Principal Investigator and Assistant Professor, University of Central Florida)
  • Laura S. Bruckman (Research Associate Professor, CWRU)
  • Roger H. French (Kyocera Professor, CWRU)
  • Joseph Walters (Program Director, Florida Solar Energy Center)
  • Sudipta Seal (Professor, UCF) 
  • Titel Jurca (Assistant Professor, UCF)
  • Mengjie Li (Postdoctoral Researcher, UCF)
  • Tamil Selvan (Research Associate, UCF)
  • Andrew Gabor (CTO, BrightSpot Automation)
  • Greg Horner (CTO, Tau Science)
  • Will Oltjen (Department of Materials Science and Engineering, CWRU)


This material is based upon work supported by the U.S. Department of Energy’s Office of Energy Efficiency and Renewable Energy (EERE) under Solar Energy Technologies Office (SETO) Agreement Number DE-EE0009347.