20 May 2016
DNV GL, the world’s largest resource of certification and energy expertise, has released the 2016 PV Module Reliability Scorecard, its second edition of a rigorous review of PV module performance. The study aims to address the lack of publicly available long-term data on reliability.
“While a 25-year performance warranty is standard in the industry, most PV modules have actually been in use less than five years, so there is a real lack of data on how equipment holds up over time,” said DNV GL’s Jenya Meydbray, the study’s lead author. “Since the first edition of the Scorecard in 2014, its findings have become a critical resource to an industry looking to understand risk.”
The Scorecard is intended to serve as a tool to compare module expected reliability and long-term performance qualitatively. The rankings provide a resource for banks, developers and independent power providers with findings to inform prudent investment in PV modules.
Nate Coleman, VP of Technical Operations for SolarCity, the United States’ biggest residential solar provider, said, “DNV GL is our trusted partner, providing the critical data that we rely on to evaluate equipment and manage our approved vendor lists.”
Nigel Cockroft, general manager of Jinko Solar USA, said, “Jinko is proud to work with an industry leader like DNV GL to offer third-party validation of our commitment to quality. This is an important part of how we work with customers and project financiers.”
The 2016 Scorecard evaluated nineteen manufacturers, including more than fifty percent of the world’s 10 largest makers of PV modules. All participants in the study are commercially available products that have already demonstrated compliance with required safety standards. DNV GL tested five major factors affecting deterioration and reliability over time: thermal cycling, dynamic mechanical load, damp heat, humidity freeze and PID (potential induced degradation).
Key findings of the 2016 Scorecard
Many module vendors performed well across all tests. For example, while the IEC pass/fail criteria allows for five percent degradation after 200 thermal cycles, eight tested manufacturers surpassed this pass/fail criteria, showing only three percent degradation after four times the IEC duration (800 thermal cycles).
Two manufacturers performed in the top group on every test: Kyocera and Phono Solar.
Approximately 55 to 60 percent of top group modules were manufactured in China. This is roughly equivalent to the ratio of Chinese module participation in the full PV Module Reliability Scorecard. This demonstrates that manufacturing location is not a good proxy for reliability.