Risk of risks in new PV technologies – PV Magazine International

A new report from IEA PVPS task 13, entitled “Demolition and failure modes in new photovoltaic cell and module technologies“Offers an extensive analysis of degradation and failure mechanisms in current photovoltaic technologies.

Relegation and failure modes changed with recent innovation

Although new technologies yield new challenges, they also lead to positive trends. The following outlines the changes in degradation and failure modes driven by current innovations.

• Cell crack -Studies show that the impact of cell cracks is largely reduced by the use of multifire technology. The cracks that are used to easily form large inactive areas, while the multi -piced cell design reduces the chance and therefore reduces the risk of power loss and hotspot.
• Lid/Letid -Licht (and increased temperature) induced demolition (member/letid) has been resolved by switching from drill to gallium as a dopant for Si-Wafers, and some other optimization measures also help. In addition, standard test procedures are available, so that the impact of the lid/Letid can be tested on the long -term performance, even for recent innovations.
• Pid -The degradation (PID) is caused by a high system tension and can be influenced by light, in particular UV. PID tests for modules with passivated emitter and rear full diffuse (pert) cells have shown that extra light can effectively occur during a PID test. In one case, it has been shown that a UV consumption radiation is equivalent to the UV content in the standard AM1.5 spectrum at 1000 Wm², the PID effect for a module with topcon cells can reduce to below 3%. In this case, on the other hand, no UV consumption during the PID test leads to a breakdown of 28%. For PV modules with SHJ cells, a new potential PID breakdown mechanism is identified. However, no modules affected by PID are found in the field that matches this mode. To assess the radiation impact on real installations, the upcoming PID standard IEC TS 62804-1 (2025) offers a combined potential and light test procedure.
• Uvid -In some PV modules for solar energy with topcon and SHJ cells, UV-induced demolition (UVID) takes place after accelerated aging tests. It is still unclear whether the relegation can be reversed by exposure to the outside air and how the test can be transferred from laboratory to the field. It should be emphasized that the UVID is a soluble problem, because some modules are UV stable in accelerated tests. Reflection or absorption of UV radiation Before it reaches the C-Si/Passivating Interfaces (eg through the Inkapsulation material), the UVID can reduce.
• Inkhadeling Demolition and failure -Current standardized PV modulet tests (eg the IEC 61215 series) often do not reveal relevant demolition paths because their focus is on the electrical performance of the PV modules, but not on the stability of the polymer materials. That is why many PV modules are found in the field with damaged lamination material. Combined tensions with EC temperature changes, humidity and UV radiation can reveal these polymer-related demolition paths. Since the degradation of incoming material material cannot be reversed and often leads to safety problems, these additional tests are recommended for new incoming materials.
• Glass fracture – Thin glass (thickness ≤ 2 mm) used in new glass/glass modules sometimes results in unpredictable fracture speeds with high glass. In documented cases, 5% to 10% of the rear glasses broke in the first two years after installation. The mechanical loading test according to IEC 61215 cannot detect this weak point, because it requires parallel tests on dozens of modules instead of just one to assess the failure percentage.
• Bad contacts in Junction Box -The electrical contacts in the connection boxes are often incorrectly soldered because of the new module -Lay -out has shorter cross connection ribbons, resulting in more disconnection of the bypass period (BPD). Errors in the connection box can lead to fires and power losses in full moduler series. However, non -bound BPDs are difficult to detect in PV systems that have already been installed. The report recommends checking the function of 100% of the BPDs during production. A PV system installation must be tested 100% if there are indications that this type of failure takes place in the selected modules.
• MHP-based PV technology -This report also contains a concise summary about the reliability of PV modules based on metalhalhalic perovskiet (MHP) based on current scientific literature. There are many well -known demolition paths for which remedies exist at conceptual or laboratory level. Protective encapsulation against UV radiation, moisture and oxygen, for example, in fact helps to stabilize the perovskite solar cells. In addition to others, however, two prominent challenges are the temperature and stability of ion migration. The limited temperature stability and high ion mobility lead to unsolved breakdown routes under normal working conditions such as shade and high system voltage. There are new breakdown modes in tandem solar cells with MHPs. The reverse voltage states that occur in the upper and soil cells during shaded conditions, for example, depend on the radiation spectrum and cannot yet be reproduced by standard qualification tests. New tests that tackle these shadow conditions are important to evaluate new breakdown paths that do not occur in PV modules with one junction.

Conclusion

This report is aimed at a wider audience, including cell and module manufacturers, as well as PV system owners. It offers detailed explanations of degradation modes, their impact on the performance of module/system, methods for identification and testing and potential mitigation strategies. Updated photovoltaic failure magazines (PVFs) Based on the report, the IEA PVPS website can also be downloaded.

This article is part of a monthly column by the IEA PVPS program.

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