PVEL’s Damp Heat (DH) test simulates long-term degradation and failure modes that are typical in high temperatures and high humidity conditions where moisture and heat can weaken the materials binding the PV module together. When the adhesiveness of these materials weakens due to low-quality components and/or substandard lamination processes, moisture can enter the laminate and corrode internal materials. The result is potential performance loss and safety issues.
Why Damp Heat Testing Matters
1.3% median degradation. 1.5% average degradation.
1.0% median degradation for glass//glass versus 1.9% for glass//backsheet.
Average degradation was 1.2 to 1.7% across CdTe, HJT, PERC and TOPCon.
DH-related power loss failures drop to zero.
Power Degradation of Each Model Type
Percentage of results shown that are post-BO stabilization: 19% of 2018, 46% of 2019, 95% of 2022, 86% of 2021. All 2022 results are post-DH2000 (pre-BO stabilization), which is the stage in DH testing used to determine Top Performers for the 2023 Scorecard. Some outliers with >10% degradation are not shown.