DuPont exposes rapid increase in PVDF backsheet material failures used in solar panels

Share on facebook
Facebook
Share on twitter
Twitter
Share on linkedin
LinkedIn
Share on reddit
Reddit
Share on email
Email

DuPont Photovoltaic Solutions' annual 'Global Photovoltaic Reliability Report' for 2020 has identified a rapid increase of cracking in PVDF (Polyvinylidene Fluoride) backsheets after inspecting more than nine million PV panels. 

Having conducted field inspections at more than 551 existing installations, DuPont said it had observed many examples of widespread backsheet material failures, notably the emerging trend of cracking in PVDF backsheets. 

This was notable in the overall outer layer cracking rate of PVDF backsheets, which had increased four-fold (from 5 to 23%) in module arrays in the field for between four and nine years, according to DuPont. Overall, outer layer cracking rates for PVDF backsheets had increased by more than three times compared to previous studies.

DuPont said it had observed many examples of widespread backsheet material failures, notably the emerging trend of cracking in PVDF backsheets. Image: DuPont

The widespread problem of PVDF backsheet through-cracks was observed along busbar ribbons, which meant that with continued weathering could extend to cell gaps and other regions of the modules. Deeper backsheet cracks had also led to backsheet delamination issues.

Dr. Kaushik Roy Choudhury, senior scientist and global technology leader, DuPont Photovoltaic Solutions said, “Delamination and cracking were observed in multiple double glass module installations. Delamination appears to originate near edges of a module or at individual cells, while cracks likely originate at scratches or chips on glass surfaces and edges or at stress risers introduced by the racking system”.

Problems included arcing and shorts, which would often lead to localised burn-through and sometimes full module fires, noted DuPont. This would also be noted in reported inverter tripping and ground faults.

Exacerbating this issue was that DuPont had identified PVDF backsheet cracking in countries such as China, Europe, India, North America and the Mediterranean region, strongly indicating that there was not a clear correlation between cracking and climate conditions as cracking of these backsheets had been observed in hot-arid, cold-arid and temperate weather conditions. 

In general, DuPont has found that inner layer cracking has been found in fluoroethylene vinyl ether (FEVE) and polyethylene terephthalate (PET) backsheets. In last year’s report, DuPont noted higher backsheet failures when using PET and glass/glass modules.

DuPont has found that inner layer cracking has been found in fluoroethylene vinyl ether (FEVE) and polyethylene terephthalate (PET) backsheets. Image: DuPont

The number of PV panels surveyed in the 2020 report increased from 6.5 million in 2029, to 9 million panels in the 2020 report. Site inspection also increased from 355 in 2019, to 551 in the latest report. 

Read Next

June 2, 2021
The first phase of GCL System Integration Technology's (GCL-SI) 60GW module factory in Hefei, in China’s Anhui Province, is on track to start production this September.
May 13, 2021
The solar module manufacturing subsidiary of Italian utility Enel is aiming to scale up annual production capacity to 3GW in the second half of 2023, the company has confirmed.
April 28, 2021
Renewable energy group BayWa r.e. has opened what it claims is its largest PV warehouse in Europe yet in a bid to expand its distribution network in the continent.
PV Tech Premium
April 20, 2021
‘Solar Module Super League’ (SMSL) member Canadian Solar is planning to launch its first N-type heterojunction (HJ) PV modules in the second half of 2021, PV Tech can reveal.
April 14, 2021
Meyer Burger is on track to start shipments of its first heterojunction (HJ) solar modules made in Germany to distributors in July.

Subscribe to Newsletter

Upcoming Events

Upcoming Webinars
November 10, 2021
8am (PST) | 5pm (CET)
Solar Media Events
December 1, 2021