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Delamination of ASE modules over the J-box  

Delamination of ASE modules over the J-box  

Citations

... The resilience and dependability of field-installed photovoltaic (PV) modules with an optimum energy production of at least 80% of their rated capacity is one of the key concerns for all stakeholders in the photovoltaic sector (Köntges et al., 2013;Wohlgemuth et al., 2015). Utilizing deterioration mechanisms and failure modes specific to PV modules in natural field operating situations, the long-term dependability of PV modules is explored (Halwachs et al., 2019;Santhakumari and Sagar, 2019). ...
Article
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There are two sorts of energy resources: sustainable power resources and non-sustainable power resources. Due to some negative ecological effects including air pollution, climate change, and resource rot, people are concentrating on using sustainable energy resources to produce electricity. Solar energy, usually referred to as sun-oriented energy, is one of the most frequently researched environmentally beneficial power resources. In order to fulfill the growing demand for energy and increase energy efficiency, Bagwari et al.: Solar Energy Technology: Step Towards Bright Future of the World … 983 | Vol. 7, No. 6, 2022 new developments and advancements in the field of solar energy are required. There are two sorts of energy resources: sustainable power resources and non-sustainable power resources. Due to some negative ecological effects including air pollution, climate change, and resource rot, people are concentrating on using sustainable energy resources to produce electricity. Solar energy, usually referred to as sun-oriented energy, is one of the most frequently researched environmentally beneficial power resources. In order to fulfill the growing demand for energy and increase energy efficiency, new developments and advancements in the field of solar energy are required. The traditional solar energy cell's inability to create power in the evening is a horrible flaw. This investigation focuses mostly on solar-powered energy and discusses its evolution, improvements, and future perspectives.
... Unfortunately, the adhesion between EVA, PVB, TPO encapsulants and PV components must be improved using suitable adhesion promoters/primers, such as trialkoxy silane. [9] According to the literature, interface encapsulation/glass is stronger than encapsulation/cell [10][11][12], and for both interfaces, the use of adhesion promoters/primers is required to facilitate and ensure correct PV assembly. [13][14][15] Unfortunately, the adhesion promoters/primers could degrade during PV module lamination and assembly, developing low molecular weight gas, which could cause delamination and often precede corrosion in fielded PV modules. ...
Article
In this work, polymer blends based on ethylene vinyl acetate (EVA) and polyolefin (PO) at different weight ratios, also in the presence of a crosslinking agent (CA) and stabilizers (STAB), were investigated as potential encapsulants for PV modules. The EVA/PO blends were processed by melt mixing and then subjected to compression moulding following industrial lamination processing conditions. The EVA/PO films were characterized by mechanical tensile tests and thermogravimetric analysis, and the obtained results highlight the beneficial effect of PO at low amounts on the mechanical behaviour and thermal resistance at high temperatures (>300°C). All EVA/PO films were subjected to UVB exposure, and the photoaging extent was monitored by FTIR and UV-visible spectroscopies. Therefore, EVA-rich blends can be considered as good candidates for PV module encapsulants, given a compromise in the behaviour before and after photoaging.
... Durability and reliability of field installed photovoltaic (PV) modules over their useful lifetime of ca. 25 years (35 years proposed) with optimal energy output of not less than 80% of their rated capacity is one of the foremost concerns for all parties in the photovoltaic business (Köntges et al., 2014;Wohlgemuth et al., 2015). The long-term reliability of PV modules can be studied more accurately from the degradation mechanisms and the fault modes associated with PV modules in natural field operating conditions Santhakumari and Sagar, 2019). ...
... A typical moisture ingressed PV module showing signs of corroded metal grids, delamination and discolouration of encapsulants. . Adapted from Wohlgemuth et al. (2015) polymers due to their structure and stresses they are exposed to. Though it was not directly related to PV applications, it served as a foundation for investigating this phenomenon in PV devices as they are also made with polymeric materials. ...
Article
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Moisture ingress in photovoltaic (PV) modules is the core of most degradation mechanisms that lead to PV module power degradation. Moisture in EVA encapsulant can lead to metal grids corrosion, delamination and discolouration of encapsulants, potential induced degradation, optical and adhesion losses. The present work is a review of literature on the causes, effects, detection, and mitigation techniques of moisture ingress in PV modules. Literature highlights on determining the diffusivity, solubility, and permeability of polymeric components of PV modules via water vapour transmission rate tests, gravimetric, and immersion methods, have been presented. Electroluminescence, photoluminescence, and ultraviolet fluorescence spectroscopy, as well as dark lock-in thermography are some techniques used to detect moisture ingress in modules. Encapsulants with excellent moisture barrier and adhesion characteristics, desiccant-stacked polyisobutylene sealants, imbedded moisture sensors, and PV designs with/without breathable backsheets are ways of preventing/detecting moisture ingression in PV modules. Areas of focus for future research activities have also been discussed.
... Photovoltaic (PV) modules are reliable tools for harvesting clean electrical energy from the sun [1]. However, studies show that PV modules can degrade in the field under multiple environmental or climatic stressors such as temperature, humidity, ultraviolet radiation, wind, and snow loads [2][3][4]. This leads to reliability issues such as cracks, moisture ingress, corrosion, delamination, discolouration, and optical degradation which can induce power degradation in these devices [3,5,6]. ...
... Remarkably, the encapsulant delamination is considered to be one of the main degradations that affect the PV modules' overall performance. As discussed previously, various forms of encapsulant delamination were identified in the field, including front glass-encapsulant delamination, cells, interconnecting ribbons, and back sheet [57,58]. Conversely, they mostly share some of the effects, causes, and mechanisms, and they differ in impacting PV modules. ...
Article
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The reliability of photovoltaic (PV) modules operating under various weather conditions attracts the manufacturer’s concern since several studies reveal a degradation rate higher than 0.8% per year for the silicon-based technology and reached up to 2.76% per year in a harsh climate. The lifetime of the PV modules is decreased because of numerous degradation modes. Electromigration and delamination are two failure modes that play a significant role in PV modules’ output power losses. The correlations of these two phenomena are not sufficiently explained and understood like other failures such as corrosion and potential-induced degradation. Therefore, in this review, we attempt to elaborate on the correlation and the influence of delamination and electromigration on PV module components such as metallization and organic materials to ensure the reliability of the PV modules. Moreover, the effects, causes, and the sites that tend to face these failures, particularly the silicon solar cells, are explained in detail. Elsewhere, the factors of aging vary as the temperature and humidity change from one country to another. Hence, accelerated tests and the standards used to perform the aging test for PV modules have been covered in this review.
... Further, in the last decade, numerous reviews that address the degradation mechanisms mentioned before have been published. Some of them describe the causes and effects of the different mechanisms on PV modules [43][44][45][46][47], whereas others are focused on a particular issue, such as aging [48], light induced degradation (LID) [49], encapsulant degradation [50,51], cell technology [52] and soiling [53][54][55][56][57]. The aim of this study is to provide a comprehensive review on the main degradation mechanisms that affect PV modules, with a special focus on their spectral impacts. ...
... Delamination of a 20-years aged Siemens M55 Module. [52] As it has been mentioned previously, delamination is strongly linked to corrosion [117], which is discussed in the following subsection. ...
Preprint
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The exponential growth of global capacity along with a reduction in manufacturing costs in the last two decades has caused photovoltaic (PV) energy technology to reach a high maturity level. As a consequence, currently, researchers from all over the world are making great efforts to analyse how different types of degradation impact this technology. This study provides a detailed review of the impact of different optical degradation mechanisms, which mainly affect the transmittance of the top-sheet encapsulant, on the spectral response of the PV modules. The impact on the spectral performance of PV modules is evaluated by considering the variations of the short-circuit current since this is the most widely used parameter to study the spectral impact in outdoors. Some of the most common types of optical degradation affecting the performance of PV modules worldwide, such as discoloration, delamination, aging and soiling have been addressed. Due to the widely documented impact of soiling on the spectral response of modules, this mechanism has been specially highlighted in this study. On the other hand, most of the publications analysed in this review report optical degradation in PV modules with polymeric encapsulant materials. Furthermore, an innovative procedure to quantify the spectral impact of degradation on PV devices is presented. This has been used to analyse the impact of two particular cases of degradation due to soiling and discoloration on the spectral response of different PV technologies.
... The degradation of field-aged PV modules has been investigated already for a long time [10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25] starting already in the mid-1980s. Back then, the most reported degradation mechanisms were severe discoloration, delamination and corrosion [25]. ...
... There are publications dealing with degradation of PV modules with regards to materials of PV components [10,14,16,21,40,47], cell-technology [15,24,57], age of modules [17], stress factors (climate) [11][12][13], type of failure modes [23,24] or producer [18]. However, the relationship between polymeric materials, climate and degradation of PV modules was not covered so far. ...
... There are publications dealing with degradation of PV modules with regards to materials of PV components [10,14,16,21,40,47], cell-technology [15,24,57], age of modules [17], stress factors (climate) [11][12][13], type of failure modes [23,24] or producer [18]. However, the relationship between polymeric materials, climate and degradation of PV modules was not covered so far. ...
Article
During their outdoor service, photovoltaic (PV) modules are exposed to different set of external stresses that can affect their efficiency and lifetime such as UV irradiation, temperature and humidity cycles, rain, snow and wind loads, hail, sand and/or salt. Moreover, internal stresses such as choice of materials and design (additives, morphology and compatibility of materials) can drive degradation of PV modules as well. The failure data collection started already in 1980s and is still ongoing. Most of these studies are focused mainly on power data or categorizing PV failure modes concerning solely climate, EVA or cell-technology. However, relationship between climate, degradation of polymeric materials and degradation of PV modules has not been reported so far. Hence, within this study a lot of effort was put into finding the appropriate data and publications with as many as possible data on PV, climate and materials degradation. As a result, a great overview of climate and polymeric materials induced PV failure modes is given. Based on the reported data, the topic of new, climate-based design of PV modules is discussed. This paper provides numerous number of selected references that can be beneficial in further studies on degradation of PV modules, design of PV modules and choice of materials.
... The degradation of field-aged PV modules has been investigated already for a long time [10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25] starting already in the mid-1980s. Back then, the most reported degradation mechanisms were severe discoloration, delamination and corrosion [25]. ...
... There are publications dealing with degradation of PV modules with regards to materials of PV components [10,14,16,21,40,47], cell-technology [15,24,57], age of modules [17], stress factors (climate) [11][12][13], type of failure modes [23,24] or producer [18]. However, the relationship between polymeric materials, climate and degradation of PV modules was not covered so far. ...
... There are publications dealing with degradation of PV modules with regards to materials of PV components [10,14,16,21,40,47], cell-technology [15,24,57], age of modules [17], stress factors (climate) [11][12][13], type of failure modes [23,24] or producer [18]. However, the relationship between polymeric materials, climate and degradation of PV modules was not covered so far. ...
Article
During their outdoor service, photovoltaic (PV) modules are exposed to different set of external stresses that can affect their efficiency and lifetime such as UV irradiation, temperature and humidity cycles, rain, snow and wind loads, hail, sand and/or salt. Moreover, internal stresses such as choice of materials and design (additives, morphology and compatibility of materials) can drive degradation of PV modules as well. The failure data collection started already in 1980s and is still ongoing. Most of these studies are focused mainly on power data or categorizing PV failure modes concerning solely climate, EVA or cell-technology. However, relationship between climate, degradation of polymeric materials and degradation of PV modules has not been reported so far. Hence, within this study a lot of effort was put into finding the appropriate data and publications with as many as possible data on PV, climate and materials degradation. As a result, a great overview of climate and polymeric materials induced PV failure modes is given. Based on the reported data, the topic of new, climate-based design of PV modules is discussed. This paper provides numerous number of selected references that can be beneficial in further studies on degradation of PV modules, design of PV modules and choice of materials. Abbreviations EVA Ethylene-vinyl acetate copolymer Isc [mA/cm 2 ] Short circuit current PVB Poly(vinyl butyral) Rs [ohm] Series resistance TPU Thermoplastic polyurethane Pmax [W] Maximum power PDMS Poly(dimethylsiloxane) Voc [V] Open circuit voltage TPO Thermoplastic polyolefine POE Polyolefine elastomer FF [-] Fill factor PA Polyamide LID Light induced degradation PE Polyethylene PID Potential induced degradation PET Poly(ethylene terephthalate) WVTR [g/m 2 d] Water vapor transmission rate PVDF Poly(vinylidene fluorid) OTR [cc/m 2 /24 hr] Oxygen transmission rate PVF Poly(vinyl fluorid) AATR [g/m 2 d] Acetic acid transmission rate HALS Hindered amine light stabilizer Tg [°C] Glass transition temperature IMC Intermetallic compound CTE [ppm/K] Coefficient of thermal expansion 1. Introduction Photovoltaic (PV) modules are designed to operate outdoors ≥25 years [1-4]. However, exposure to mechanical stresses, moisture, elevated temperature and ultraviolet radiation eventually degrades protective materials in PV modules, giving rise to occurrence of different failure modes, which leads to reduced solar cell performance before meeting the manufacturer's warranty of 25 years lifetime [1,5,6]. A PV failure mode is an effect that either degrades the module power, which is not reversed by normal operation, or creates a safety issue. On the other hand, a purely cosmetic issue, which does not affect the module´s performance or safety, is not considered as a PV module failure [6]. Nevertheless, purely cosmetic issues may trigger/enhance other failure modes or indicate presence of other visually not observable failures that do affect power output. For instance, rather newly addressed failure mode "snail trails" are discolorations on the cell and there is no yet indication that they cause a significant decrease of module efficiency. However, the presence of "snail trails" is an indication of cell cracks [7-9]. Furthermore, during transport and installation, which are the first critical stages in a PV module's life, glass breakage is one of the most occurring defects. Although this observation is not a failure mode that affects cell performance directly, it is still promoting or even causing other failure modes to occur like failed electrical insulation, corrosion, delamination, etc. [6]. The degradation of field-aged PV modules has been investigated already for a long time [10-25] starting already in the mid-1980s. Back then, the most reported degradation mechanisms were severe discoloration, delamination and corrosion [25]. However, the results obtained in these early field inspections are not representative for today's PV modules since the type of lamination materials being responsible for the observed delamination and discolouration were replaced with new formulations. It is also important to note that some of the mechanisms observed recently (like cell cracks or hot spots), could not be detected in former times due to lack of required technology. Nevertheless, the knowledge of the most important long-term degradation mechanisms for sure helped in quantifying long-term behaviour and lifetime of PV modules, tailoring the properties of materials for PV components and qualification tests of today's PV modules [6,15]. The most common qualification test in use is based on standard IEC 61215 [26], which indicates early product life (infant) failures due to choice of design, process and materials [2,26-29]. Namely, this qualification test is based on set of defined experiments with strict pass/fail criteria for infant failures and is recognized as not predictive of long term performance [1,4,27,29,30]. It defines power loss of more than 5% as fail, while values below 5% are considered as pass [21,26,30]. However, in order to prevent field failure, it is still important to understand where any power loss (even below 5%) is coming from and to prevent its future occurrence [30]. Even though most of PV module manufacturers carry out qualifications tests on their PV modules, not much reliability testing is done in industry [1,30]. According to Wohlgemuth et al. [4], it is necessary to use reliability tests that go beyond the qualification test. Reliability tests are designed to evaluate failures, to quantify them and to help understand the failure mechanisms in order to improve the reliability of
... The types of defects which are sought in photovoltaic modules are based on literature review (Djordjevic et al., 2014;Dubey et al., 2014;Wohlgemuth et al., 2015;Kuitche et al., 2014;Munoz et al., 2011;Ndiaye et al., 2013a;Sharma and Chandel, 2016): 2.3.2.1. Discoloration. ...
Article
The paper reviews the different detectable failures of mono-crystalline and poly-crystalline silicon in the research unit in renewable energies in Saharan medium (URERMS) fields. This survey is an effort to inspect and assess the defects of PV modules occurring in recent and older installations in a desert environment and under real operating conditions. The analysis and evaluation of 608 PV modules inside the site of URERMS and in a remote located solar installation (Melouka) using the visual inspection test results in the following failures and degradation modes: delamination, discoloration of the encapsulant, corrosion and discoloration of the metallization (gridlines, busbar, cell interconnect ribbon and string interconnect), solar cell cracks, broken glass, deterioration of the antireflection coating, snail trails, junction box failure, soiling. The electrical performance of some tested modules is also performed in order to give the correlation with the visual defects.
... Mobil Solar/ASE America type 300-DGF/50 modules produced for a period of several years around 2001 have frequently been seen in the field exhibiting delamination, Fig. 4. These are glass/glass construction and from the literature and visual inspection, these modules had a specific ionomer encapsulant [35] that has proven to have insufficient adhesion. Delamination occurred frequently over the junction boxes and at the edges. ...
Technical Report
Full-text available
In this report we present the current status and predictive ability for the power loss of PV modules for specific failure modes. In order to model PV module degradation modes it is necessary to understand the underlying degradation mechanisms and processes on the molecular level. In most cases the encapsulant and backsheet films seem to play a major role in PV module degradation. Some failure modes like browning of encapsulants are directly related to the encapsulant film. But in most cases material interactions are the main root cause for PV module degradation. For example, acetic acid, which is a degradation product of EVA encapsulants, not only causes corrosion of the PV stringing and tabbing ribbons and the PV cell gridlines or fingers, but also promotes potential induced degradation and/or delamination. Furthermore, it accelerates the oxidation process of EVA itself. Also, the type of backsheet used in the PV module influences many degradation mechanisms by its barrier properties against water vapour, oxygen, and acetic acid. High concentrations of water vapour and acetic acid in the PV module accelerate nearly all degradation modes. The literature review shows that PV module failure modes are well described in the literature, including their main driving factors. The review also shows that the right combination of the encapsulant and backsheet films can be beneficial in reducing failures. Nevertheless the studies also show that there are no common rules or acceleration factors which apply generally for all PV modules and can be used for modelling. On the one hand, the degradation modes depend on the bill of materials and components and are unique for each single PV module brand and model. On the other hand, there are typically several degradation modes and pathways activated simultaneously and these may have synergistic or antagonistic effects, making it challenging to correlate observed effects with single mechanisms. For wellknown PV module failure modes, modelling approaches to forecast the power loss are summarized from the literature. All these models are based on the principle understanding of the underlying process, but they are still only heuristic models which do not include the influence of material parameters. So the models are parameterized by the test results of whole modules and not on test results of the module components. To identify the impact of the various failures a survey on the impact of PV system failures in various climatic zones is conducted. The results do not show a strong correlation of the observed failure occurrences and impacts with the Köppen and Geiger climatic zones. In the future larger datasets of observations may enable these insights, while additional factors which need to be considered for PV module failures may be identified. Independent of climatic zones some PV module failures stand out with a high power loss if a PV system is affected by the failure. In the rank order of impact, these failures are potential induced degradation, failure of bypass diodes, cell cracks, and discolouration of the encapsulant (or pottant) material. This rank order of failure modes may be a result of the fact that for potential induced degradation, bypass diodes, and discolouration of the pottant material no appropriate tests exist in the standard IEC61215 design qualification and type approval test. Currently for all these failure types tests are in development, but they are not even included in the current revision of the IEC61215. Therefore, we recommend PV plant designers not only to check for an approved IEC61215 test for the PV module brands/models considered for use, but also for additional tests for PID (IEC/TS 62804 series), bypass diode test (IEC 62979, IEC/TS 62916). The UV degradation test is slightly tightened in the current IEC 61215 compared to the former one, but there is still no pass/fail criterion for discolouration. However, it is recommended to read the full protocol of an IEC 61215 test and look for discolouration remarks. Besides PV module failure, the failure with the highest impact on the PV system is the soiling of PV modules in specific outdoor regions. The soiling also does not strongly correlate with the climate zones of Köppen and Geiger. Therefore, a special stressor classification for PV modules for soiling in the Middle East and North Africa regions is introduced. These classifications are derived by geographic information systems to allow a worldwide mapping of relevant stress factors for PV systems. In the future this stress factor mapping has to be expanded to other regions worldwide and for other stress factors than soiling.