California-based independent engineering and certification test laboratory Renewable Energy Test Center (RETC) has released its “2025 PV Module Index Report,” which tests solar panels for reliability, performance and quality.
This year, RETC recognized 21 module manufacturers for high achievement across 14 testing sequences. RETC also identified 12 manufacturers as meeting the criteria for its “Overall Highest Achiever” recognition. The 12 manufacturers are: Astronergy, DASolar, DMEGC, JA Solar, JinkoSolar, Longi, Runergy, SolarSpace, Trina Solar, VSUN, Waaree and Yingli Solar.
To be recognized as an Overall Highest Achiever, manufacturers must successfully complete RETC’s rigorous Thresher Test program and excel across multiple tests within the reliability and performance disciplines. Manufacturers must also demonstrate a commitment to quality control and assurance by allowing an independent third party to randomly select PV modules from inventory for Thresher Testing.
RETC reserves Overall Highest Achiever recognition for manufacturers of bills of material (BOMs) that excel across three interrelated and equally influential disciplines: module reliability, performance and quality. A step down from this top honor, RETC recognizes manufacturers of products that excel across multiple testing sequences within one specific discipline for “High Achievement in Reliability” or “High Achievement in Performance.”
the 2025 report found an increase in issues related to humidity, thermal cycling, PID and metastability. RETC also found structural issues, like module frame and glass failures during mechanical loading.
“Though some recent bankability test results are alarming, these are also issues that the technical due diligence community has successfully eradicated in the past or can resolve with improved test standards. So long as we have eyes to see them, we can solve these problems,” stated Cherif Kedir, CEO of RETC.
See the testing results here.