DNV GL has released its new PV Module Reliability Scorecard 2014, that found that nearly 2/3 of the cumulative 130 gigawatts of installed solar photovoltaic modules in the world were produced in the last three years. This period marked record module price reductions as well as module manufacturers’ aggressive cost reductions. This cost reduction, finds the Scorecard, has led to questions around long-term PV performance and module quality while at the same time, projects are being built in more extreme and diverse environmental condition then ever before.

To address these concerns, the Scorecard identifies module manufacturers’ reliability performance from 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 has compiled data from DNV GL’s highly accelerated life testing (HALT) on major global PV module manufacturers. Participating manufacturers 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 and allows the industry to identify 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 report author and 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 & 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.