| Aug 10, 2026
Abstract
Reusing decommissioned solar modules requires fast and reliable ways to determine which modules still have useful life remaining. Current-voltage (I-V) measurements are widely used for this purpose, often alongside electroluminescence (EL) imaging, but it is important to understand what these methods can (and cannot!) tell us about a module's condition.
In this study, we developed an automated, two-stage I-V screening framework and applied it to 3,749 decommissioned PV modules from more than 100 manufacturers. The approach uses explicit, reproducible acceptance criteria to identify degraded modules and estimate their residual useful life, providing a more consistent alternative to manual I-V assessment.
We then compared the screening results with 1,963 wet-leakage measurements performed according to IEC 61215, and evaluated EL imaging as an additional indicator of module degradation. The comparison revealed an important limitation: around 14% of modules that passed combined I-V and EL screening still failed insulation resistance testing.
The results show that electrical performance, structural condition and insulation resistance represent different aspects of PV module health. I-V analysis and EL imaging can provide efficient, scalable tools for assessing performance and remaining service value, but they cannot replace dedicated electrical safety testing when qualifying modules for second-life deployment.
The study also highlights how strongly reuse decisions can depend on the chosen acceptance criteria, and the presented approach provides a basis for more transparent and reproducible qualification standards.
In this study, we developed an automated, two-stage I-V screening framework and applied it to 3,749 decommissioned PV modules from more than 100 manufacturers. The approach uses explicit, reproducible acceptance criteria to identify degraded modules and estimate their residual useful life, providing a more consistent alternative to manual I-V assessment.
We then compared the screening results with 1,963 wet-leakage measurements performed according to IEC 61215, and evaluated EL imaging as an additional indicator of module degradation. The comparison revealed an important limitation: around 14% of modules that passed combined I-V and EL screening still failed insulation resistance testing.
The results show that electrical performance, structural condition and insulation resistance represent different aspects of PV module health. I-V analysis and EL imaging can provide efficient, scalable tools for assessing performance and remaining service value, but they cannot replace dedicated electrical safety testing when qualifying modules for second-life deployment.
The study also highlights how strongly reuse decisions can depend on the chosen acceptance criteria, and the presented approach provides a basis for more transparent and reproducible qualification standards.
Reference
M. Ernst, R. Basnet, and C. J. Fell, "Data driven I-V analysis for qualification of decommissioned PV modules for second life deployment,", Solar Energy Materials and Solar Cells, vol. 307, p. 114629, 2026, doi: 10.1016/j.solmat.2026.114629.
Tags | Modules, Sustainability, Re-Use