⚡ Quick Read
- What happened: Researchers at UFSC validated that 23-year-old polycrystalline solar modules retain 87-88% of original power with stable annual degradation rates of approximately 0.44%.
- Why it matters: While technically viable, the economic case for second-life modules remains challenging as new, high-efficiency panel prices continue to decline.
- Watch: Future developments in circular economy policy and potential regulatory frameworks for secondary PV module markets.
Background and Context
As the global solar industry matures, the challenge of managing decommissioned assets is becoming increasingly critical. Researchers at the Federal University of Santa Catarina (UFSC) in Brazil recently concluded a two-year study on the viability of second-life polycrystalline solar modules. The study focused on 76 modules, totaling 4.7 kW, which were originally installed on Ratones Island to replace diesel generation. After operating for over 22 years, the system was decommissioned in 2022 to make way for higher-efficiency technology, providing a unique opportunity to test the long-term durability of aging hardware.
Key Details
Following decommissioning, the modules underwent rigorous visual, electrical, and safety assessments at the UFSC PV laboratory. Approximately 68% of the modules were cleared for second-life use. The research team subjected these units to two distinct configurations: a module-level outdoor setup on a single-axis tracker and a system-level grid-connected installation. Between 2023 and 2025, the team conducted continuous IV curve measurements, electroluminescence imaging, and thermal drone inspections.
The findings revealed that the modules retained 87–88% of their original power capacity. Furthermore, the degradation rate remained stable at approximately 0.44% per year. Despite these positive technical indicators, lead author Ricardo Rüther noted significant market barriers. He highlighted that while the circular economy case is strong, the economic argument is difficult to sustain because the price of state-of-the-art silicon PV modules continues to drop. Currently, second-life modules would need to be priced at least 50% below new market rates to be competitive, a threshold that is difficult to guarantee alongside murky warranty offerings.
What This Means for EPCs and Developers
For Indian EPC contractors and developers, this study offers a proof-of-concept for the technical reliability of older assets. However, the findings underscore a pragmatic reality: the secondary market for PV modules is currently hampered by the rapid deflation of new panel prices. For developers looking at repowering projects, the data suggests that while old modules can technically continue to function, the operational expenditure associated with testing, certification, and the lack of long-term warranties may outweigh the capital savings of reusing hardware. Developers should prioritize high-efficiency, new-generation modules to maximize land-use efficiency and bankability.
What Happens Next
The industry must now monitor how circular economy mandates evolve. As India scales its solar capacity toward ambitious 2030 targets, the volume of decommissioned panels will grow exponentially. Future developments to watch include the potential emergence of standardized testing and certification protocols for second-life modules, which could eventually provide the warranty security necessary to make these assets commercially viable for off-grid or low-cost applications.
