The latest report of the Kiwa PV Evolution Labs (PVEL), the 2024 PV Module Reliability Scorecard, saw a much larger participation of manufacturers than ever before, but also the highest percentage ever reported for failures. According to the report, 66% of module manufacturers experienced at least 1 failure.
"Our 2024 Scorecard showcases strong results across a diverse group of solar module manufacturers, which reflects the excellence and growth we have observed in PV manufacturing in recent years," said Managing Director of Kiwa PVEL, Kevin Gibson.
The 10th edition of the scorecard named 53 manufacturers and 388 model types as Top Performers in one or more of the tests. At least 8 manufacturers were named as Top Performers under all categories.
The categories under which these were tested as thermal cycling (TC), damp heat (DH), mechanical stress sequence (MSS), potential-induced degradation (PID), UVID sensitivity, LETID sensitivity, PAN file & IAM profile, field exposure, backsheet durability sequence, and the new test category of hail stress sequence (HSS).
According to the Kiwa PVEL analysts, less than 6% of the Top Performer models achieved this status in all reliability tests. Only 4 models were Top Performers in those, plus PAN.
They found 84% of the unique bill of materials (BOM) degrading by less than 2%, with a median degradation of 0.8% following TC. However, the number of outliers and failures increased.
For PERC and TOPCon, the median power degradation rate was 0.6% and 0.7%, respectively. For TOPCon modules, the number of power degradation failures was higher. As for heterojunction (HJT) BOMs, these showed improved TC results, compared to previous years.
In terms of the DH test, 85% of glass-glass BOMs had degradation of less than 2% following DH2000, but only 46% of glass-backsheet BOMs met this threshold, according to the report.
The MSS test led to 7% of BOMs experiencing one or more failures, with 9 manufacturers experiencing at least 1 failure during the testing, including glass breakage, frame breakage and delamination.
A total of 89% of the 2.0 mm heat-strengthened glass-glass modules experienced glass breakage due to 50 mm hail during the HSS test. For 3.2 mm fully tempered glass-backsheet modules, this was 40%.
Kiwa PVEL says its hail testing has been almost exclusively for 2.0 mm glass-glass and 3.2 mm glass-backsheet, but 3 tested BOMs of 2.5 mm glass-glass showed no glass breakage with 50 mm hail.
Under the PAN test, the scorecard shows the average HJT bifaciality as 86.7% compared to 75.4% for TOPCon and 69.3% for PERC. Analysts say this leads to significantly higher modeled energy yield for HJT, followed by TOPCon, when compared to PERC modules.
The complete scorecard can be accessed on Kiwa PVEL's website.
In its last scorecard, PVEL reported strong results for TOPCon and HJT modules (see 9th PV Module Reliability Scorecard).