Congratulations to our 2025 PVMI Awardees
Analyzing our annual PV module test results, 13% of models tested met RETC’s rigorous standard for our top accolade—recognition as an “Overall Highest Achiever.”
Overall Highest Achievers
In this preliminary June 2025 release of the PV Module Index Report, RETC has recognized 21 module manufacturers for some form of high achievement across the 14 different testing sequences included within the reliability and performance disciplines. As was the case last year, we will publish a final report release in September 2025, which will capture the results of any remaining long-duration testing sequences.
To identify top PV module models and manufacturers in our annual data set, we first evaluated data distributions within specific sequences. We then identified thresholds for high achievement and red-flag results based on engineering best judgment and a review of scientific literature. Subsequently, we analyzed these summary data and established holistic criteria for recognition, which are included in this report for transparency.
To achieve RETC’s top honor, module companies had to meet high-achievement criteria in three disciplines: module reliability, performance, and quality. In other words, “Overall Highest Achiever” status effectively indicates that RETC recognizes these companies for “High Achievement in Reliability,” “High Achievement in Performance,” and “High Achievement in Quality.” This is an exceptionally high bar to pass.
Based on a thorough review of beyond-qualification test results collected at RETC’s highly accredited independent testing laboratories between Q2 2024 and Q1 2025, we have identified 12 manufacturers that met or exceeded our rigorous criteria for our “Overall Highest Achiever” recognition. RETC commends these module companies for consistently achieving excellence in PV module manufacturing.
2024 PV Module Index Report Overall Highest Achievers
Caveat emptor
While laboratory-observed module reliability and performance indicators trended in a positive direction on a year-over-year basis, we remind downstream stakeholders that due diligence for project procurement is considerably more complex than simply entering into a supply agreement with a manufacturer we have recognized for high achievement in PV module manufacturing. Even the best module manufacturers sometimes make PV modules that underperform in Thresher Test sequences. Buyers who want to source high-quality BOMs and avoid low-quality ones should request a copy of RETC’s Thresher Test report from the manufacturer.
Representing an extreme downside scenario, a PV module model submitted by a developer to RETC for Thresher Testing in 2023 returned red-flag results in both reliability and performance test sequences. Upon further investigation, we discovered that these test samples had not been directly sourced from a factory but had been stored for an unknown period in a warehouse and subsequently resold. This double red-flag result serves as a reminder that the bitterness of poor quality persists long after the sweetness of a low price is forgotten. If a deal seems too good to be true, it usually is.
Outlier cases aside, a more pervasive procurement threat is currently hiding in plain sight. Today, established solar manufacturing landscapes and supply chains are shifting in unprecedented ways, in some cases driven by tax credits and other incentives, but more often by duties, tariffs, and other regulatory pressures. It is difficult to build a foundation for success on these shifting sands. In recent rounds of bankability testing, RETC has observed an increase in PV cell-related issues, many of which have not been seen in our bankability testing for the better part of a decade, underscoring the importance of having a plan in place to mitigate supply chain risks.
Recent testing has also shown how novel technologies tend to degrade in novel ways, revealing evidence of structural deficiencies, such as PV module frame and glass failures during mechanical loading, cyclical loading, and ballistic-impact testing. These red-flag results serve as a reminder that industry stakeholders must remain vigilant regarding the technical risks inherent in an accelerated pace of change and the short time frames between innovation and mass production. It is incumbent on the technical due diligence community to anticipate teething issues associated with new technologies and product designs and to test, validate, and verify accordingly. Although we may trust in a higher power, all others must provide evidence.
Criteria for recognition
To be recognized as an “Overall Highest Achiever” in the PV Module Index Report, manufacturers must successfully complete RETC’s rigorous Thresher Test program and excel across multiple tests within the reliability and performance disciplines. Moreover, manufacturers must 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, we recognize manufacturers of products that excel across multiple testing sequences within one specific discipline for “High Achievement in Reliability” or “High Achievement in Performance.”
ABOUT RETC AND ITS PV MODULE INDEX REPORT
RETC (Renewable Energy Test Center), part of the VDE Group, is a leading provider of engineering services and certification testing for renewable energy products. Since its founding in 2009, RETC has partnered with manufacturers, developers, and investors to test a wide range of products, including solar photovoltaic (PV) modules, racking, trackers, power electronics, and battery energy storage system (BESS) components. At our accredited laboratories around the world, we evaluate products using the latest testing standards and industry-accepted methods. Headquartered in Fremont, California, RETC puts customers at the forefront by bringing value to research and development, bankability assessments, and market-entry activities. We are united with our customers in the belief that providing a foundation for energy security and effective decarbonization ensures a safer and more sustainable world.
As part of the VDE Group, one of the largest technology organizations in Europe, RETC is committed to the advancement of reliable renewable energy technologies. With this goal in mind, our seventh annual PV Module Index Report compiles the results of beyond-certification bankability tests conducted at our highly accredited independent testing laboratories over 12 months, spanning Q2 2024 through Q1 2025.
The bankability tests published in the disciplines section of this report are foundational to a science- and engineering-based approach to technical risk mitigation. The goal of a data-driven approach to project development is not to eliminate every risk at any cost but rather to balance risk mitigation based on a holistic cost-benefit analysis. With this in mind, industry stakeholders can use the comparative test results contained in this report to identify product or project designs best suited to a specific environment, location, or portfolio, as determined by RETC’s Thresher Test results.
Informed by the comparative results of highly accelerated stress testing, diligent project developers, owners, and insurers can take science- and engineering-based steps to mitigate severe weather risks and prevent catastrophic loss events. Laboratory testing data clearly show that some PV modules are more resilient to severe hail impacts, for example, whereas other products are more vulnerable. At the same time, products that test well for hail durability may be at an elevated risk of degradation when installed in a hot, humid location.
Intelligent solar project development eschews an oversimplified solar-as-a-commodity approach to project design and product procurement. All solar modules and installation environments are not the same. Success or failure in the field could come down to this simple question: What is the right tool for the job? Successful solar project deployment demands differentiated products and design approaches. These strategic design adaptations ensure that fielded projects can withstand site-specific risks while optimizing investor returns.
As a highly accredited provider of product certification and bankability testing, RETC plays an essential role in PV performance characterization and optimization. Our laboratory and outdoor testing services help manufacturers identify cell-level degradation mechanisms and module-level failure modes during product development. In parallel, our work assures owners, insurers, financiers, and independent engineers that mass-produced PV products will perform as expected during commercial operations. Our state-of-the-art testing laboratories use calibrated and certified equipment under audited and controlled conditions. Performance characteristics captured under these rigorous conditions represent the true measure of PV module performance.
Knowledge is power.
Download the 2025 PVMI today!
