Nearly two-thirds of the cumulative 130 gigawatts of installed solar photovoltaic modules in the world were produced in the last three years, a period marked by record module price reductions. During this time, module manufacturers’ aggressive cost reductions have raised questions around long-term PV performance and module quality. At the same time, PV project developers are building projects in emerging markets and subjecting PV modules to more extreme and diverse environmental conditions. 

To address these concerns and more, GTM Research and PV Evolution Labs, now DNV GL, released the new PV Module Reliability Scorecard 2014 -- a first-of-its-kind report that compares and identifies module manufacturers' reliability performance as gauged via a standardized accelerated life testing program. The Scorecard supports PV project developers, EPCs, investors and asset managers in their evaluation of leading module manufacturers and is a critical tool for quality-backed procurement strategies.

GTM Research compiled data from DNV GL's highly accelerated life testing (HALT) on major global PV module manufacturers. Participating manufacturers' modules were subject to rigorous tests designed to mimic real-world environmental stresses and identify potential long-term quality issues and failure modes. The Scorecard goes beyond standard module qualification and certification tests, identifying the spectrum of performance differences across the module vendor landscape.

In the Scorecard, GTM Research found that module vendors performed relatively well across all metrics, with a few exceptions on specific tests. However, “module reliability is not necessarily a consistent quality. Of all vendors analyzed, only one company consistently ranked within the Performance Leaders group for all test regimens,” wrote the report author, GTM Research solar analyst Jade Jones.

“While all modules met the regulatory UL requirements, long-term, real-world performance is not simply pass/fail. More robust module designs were clearly identified,” said Jenya Meydbray, head of module and inverter testing at DNV GL and former PVEL CEO. 

Tests in the Scorecard program include extended thermal cycling, damp heat, humidity-freeze, dynamic mechanical load, and potential induced degradation for positively and negatively biased modules.

Source: GTM Research's PV Module Reliability Scorecard 2014

Findings from the report stressed the importance of matching module quality characteristics with the planned installation climate. "Coupling a module’s performance capabilities with suitable install environments can prove valuable for ensuring long-term project viability," wrote Jones.

“The PV Module Reliability Scorecard is a unique module quality comparison resource that helps the PV industry identify long-term performance leaders on an apples-to-apples basis with their peers,” explained MJ Shiao, GTM Research’s Director of Solar Research. “While it may not replace in-depth bill-of-materials and manufacturing-process studies, the Scorecard is an invaluable asset in quality-backed procurement strategies for module buyers and project investors of all sizes.”


GTM Research's PV Module Reliability Scorecard aggregates highly accelerated lifetime test results from DNV GL and provides supplier performance analysis. The Scorecard helps investors and developers generate quality-backed procurement strategies to ensure long-term project viability. For more information, visit

Companies mentioned in the report include Astronergy, Inventec, Jinko Solar, Kyocera, LDK Solar, ReneSola, Suntech, Trina Solar, and Yingli Solar.