{"title":"Photovoltaics Literature Survey (No. 197)","authors":"Ziv Hameiri","doi":"10.1002/pip.3887","DOIUrl":"https://doi.org/10.1002/pip.3887","url":null,"abstract":"","PeriodicalId":223,"journal":{"name":"Progress in Photovoltaics","volume":"33 3","pages":"507-510"},"PeriodicalIF":8.0,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143380251","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
F.-J. Haug, A. Morisset, M. Lehmann, S. Libraro, E. Genç, J. Hurni, C. Ballif
{"title":"Impact of Rapid Thermal Processing on Bulk Lifetime and Surface Recombination Velocity of Crystalline Silicon With Passivating Tunnel Oxide Contacts","authors":"F.-J. Haug, A. Morisset, M. Lehmann, S. Libraro, E. Genç, J. Hurni, C. Ballif","doi":"10.1002/pip.3894","DOIUrl":"https://doi.org/10.1002/pip.3894","url":null,"abstract":"<p>We investigate rapid thermal processing (RTP) as alternative to the prolonged thermal annealing process used to form tunnel-oxide passivating contacts for silicon solar cells. The thermal treatment is generally followed by hydrogenation to passivate defects at the Si/SiOx interface. Whereas industrial manufacturing generally uses Cz wafers, research is often carried out with FZ wafers. Both types of wafers are prone to the formation of thermal defects in the bulk. To disentangle effects of the interface and the bulk, we assess the lifetime at different steps of the process sequence for both wafer types. We find that the initial bulk lifetime of our <i>p</i>-type FZ material is maintained for RTP up to temperatures of about 450°C, followed by a severe decay and eventually a moderate extent of recovery at temperatures above 800°C. Compared to FZ material, the initial bulk lifetimes in our <i>p</i>-type Cz material are slightly lower, but they are maintained on that level up to about 600°C. Beyond that temperature, the lifetimes also decay, but to a lesser extent than in the FZ material, and there is no curing at higher temperatures. Hydrogenation can partially passivate the bulk defects in FZ material, but the initial state is not recovered. In Cz material, it appears that RTP creates two different types of defects; for those created up to 800°C, the initial state can be recovered by hydrogenation whereas those created at higher temperature cannot be passivated by hydrogenation. We also investigate the formation of <i>n</i>-type passivating contacts by RTP, and we fabricate solar cell precursors with a single RTP step and the same hydrogenation for both contact polarities. After sputtering a transparent conducting ITO layer on the full area and an Ag metallization, we achieve solar cells efficiencies up to 20.5%.</p>","PeriodicalId":223,"journal":{"name":"Progress in Photovoltaics","volume":"33 9","pages":"954-961"},"PeriodicalIF":7.6,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/pip.3894","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145100901","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Efficiency Enhancement of CZTSSe Solar Cells via Thermal Treatment of (Zn, Mg)O Buffer Layers for Improving Crystallinity and Reducing Point Defects","authors":"Yafei Wang, Junsu Han, Shengye Tao, Liangzheng Dong, Qianming Gong, Hanpeng Wang, Mengyao Jia, Zhihao Wu, Maria Baranova, Jihui Zhou, Ming Zhao, Daming Zhuang","doi":"10.1002/pip.3890","DOIUrl":"https://doi.org/10.1002/pip.3890","url":null,"abstract":"<div>\u0000 \u0000 <p>The application of (Zn, Mg)O buffer layers significantly improves the energy band alignment and the interface quality of the heterojunction of CZTSSe solar cells, leading to a breakthrough in power conversion efficiency (PCE). However, (Zn, Mg)O thin films prepared by sputtering typically exhibit poor crystallinity, limiting their application. Rapid thermal processing (RTP) and substrate heating during the sputtering are investigated to address this issue. Our study demonstrates the effectiveness of RTP in reducing oxygen vacancies (V<sub>O</sub>) and adsorbed oxygen (O<sub>ad</sub>). Furthermore, it is identified that both thermal treatments increase the Mg<sub>Zn</sub>/(Mg<sub>Zn</sub> + Zn) ratio of (Zn, Mg)O thin films, thereby increasing their band gap. A notable improvement in the device performance of CZTSSe solar cells, particularly in fill factor (FF) and open-circuit voltage (<i>V</i><sub>OC</sub>), is achieved by adopting optimal thermal treatment processes. Power conversion efficiencies (PCEs) of 12.4% and 12.3% are obtained through RTP and substrate heating, which are remarkably improved compared with the untreated CZTSSe solar cells with the maximum PCE of 9.5%. Notably, 12.4% is the highest PCE for CZTSSe solar cells with (Zn, Mg)O buffers to date.</p>\u0000 </div>","PeriodicalId":223,"journal":{"name":"Progress in Photovoltaics","volume":"33 4","pages":"580-590"},"PeriodicalIF":8.0,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143555219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Performance Analysis of an Onboard PV System on a Demonstrator Light Commercial Vehicle in Hannover, Germany","authors":"Neel Patel, Evgenii Sovetkin, Bart Pieters, Karsten Bittkau, Kaining Ding, Robby Peibst, Hilke Fischer, Angèle Reinders","doi":"10.1002/pip.3897","DOIUrl":"https://doi.org/10.1002/pip.3897","url":null,"abstract":"<p>We present an analysis of the performance data of a monitored PV system onboard a light commercial electric vehicle during parking and driving conditions in the Hannover region of Germany. The PV system's nominal power is 2180 W<sub>P</sub> with flat silicon modules on the vehicle's roof, rear, left, and right sides and other electronic components needed to charge the vehicle's high-voltage (HV) battery. The analysis indicated that after 488.92 h of operation, the modules mounted on the vehicle roof produced 133.32 kWh of electricity during parking at the best possible orientation compared to 15.4, 30.67, and 22.99 kWh for the modules mounted on the rear, left, and right sides, respectively. During the trips, after 31.99 h of operation, 6.12, 0.68, 1.08, and 1.86 kWh of electricity were produced by the modules on the roof, rear, left, and right sides, respectively. The overall system efficiency was in the 60%–65% range. The aggregated usable electricity reaching the HV battery after multiple conversion stages generated by the system at the two parking locations was 129.39 kWh. PV electricity generated at the two parking locations enabled a range extension of approximately 530 km, which is 30% of the total distance driven during the measurement period between April and July 2021.</p>","PeriodicalId":223,"journal":{"name":"Progress in Photovoltaics","volume":"33 5","pages":"616-627"},"PeriodicalIF":8.0,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/pip.3897","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143762317","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Deepak Jain Veerendra Kumar, Kenneth A. Ritter III, Johnathan Richard Raush, Farzad Ferdowsi, Raju Gottumukkala, Terrence Lynn Chambers
{"title":"Optimizing Photovoltaic Soiling Loss Predictions in Louisiana: A Comparative Study of Measured and Modeled Data Using a Novel Approach","authors":"Deepak Jain Veerendra Kumar, Kenneth A. Ritter III, Johnathan Richard Raush, Farzad Ferdowsi, Raju Gottumukkala, Terrence Lynn Chambers","doi":"10.1002/pip.3891","DOIUrl":"https://doi.org/10.1002/pip.3891","url":null,"abstract":"<p>Previous studies have shown that soiling losses on photovoltaic (PV) modules can lead to reduced power output of up to 80% in PV systems. Therefore, accurate determination of soiling loss plays a crucial role in predicting PV output and ensuring optimized cleaning schedules. The study focused on measuring soiling loss at a 1.1 MW outdoor testing facility in Louisiana, United States, using a DustIQ device, a commercially available soiling sensor. The maximum soiling loss recorded for DustIQ Sensor 1 was 7.5% on August 27, 2023, during the dry season. The measured data was fitted using the well-established Kimber and HSU models (based on PM<sub>2.5</sub> and PM<sub>10</sub>) by optimizing the least squares error, resulting in observed mean absolute percentage error (MAPE) of approximately 0.82% and 0.78%, respectively. One feature of these models is that it is assumed that the solar panels will be completely cleaned after a rain event that reaches a set threshold limit. However, in-field testing at the site shows that assumption to be flawed, because the soiling ratio did not return to 1 or 100% even after significant rainfall events. To address this, improved versions of the Kimber and HSU models were developed to more accurately represent the recovery of the soiling ratio after rainfall events. The results demonstrated significant improvements, with the modified Kimber models achieving reductions in root mean squared error (RMSE) of 23%, 13%, and 1% compared to the optimized Kimber model, while the modified HSU model exhibited a 12% reduction in RMSE over the optimized HSU model. The overall MAPE was less than 1% for all models.</p>","PeriodicalId":223,"journal":{"name":"Progress in Photovoltaics","volume":"33 4","pages":"560-579"},"PeriodicalIF":8.0,"publicationDate":"2025-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/pip.3891","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143555177","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Akash Anand Verma, D. K. Dwivedi, Pooja Lohia, Surbhi Agarwal, Upendra Kulshrestha, Manish Kumar, Rahul Pandey
{"title":"Enhancing Efficiency of Lead-Free Cs2TiIxBr6-x Perovskite Solar Cells Through Linear and Parabolic Grading Strategies: Toward 31.18% Efficiency","authors":"Akash Anand Verma, D. K. Dwivedi, Pooja Lohia, Surbhi Agarwal, Upendra Kulshrestha, Manish Kumar, Rahul Pandey","doi":"10.1002/pip.3895","DOIUrl":"https://doi.org/10.1002/pip.3895","url":null,"abstract":"<div>\u0000 \u0000 <p>The most amazing environmentally friendly energy source is solar energy, which can be captured with the aid of photovoltaic (PV) cells. Perovskite solar cells (PSCs) that are hybrid (organic–inorganic) have demonstrated remarkable PV ability. The advantages of halide-based perovskite are numerous and include cheap cost, high efficiency, and simplicity in fabrication. Due to their poisonous nature, lead (Pb)-based PSCs often pose a concern to the environment. They also have other drawbacks, such as stability problems, problems with scalability, and health risks associated with Pb exposure. Thus, the primary intent of this study is to examine the Pb-free, inorganic titanium-based perovskite complex Cs<sub>2</sub>TiI<sub>x</sub>Br<sub>6-x</sub>, which serves as the active layer. When compared with other elements, titanium is nontoxic, strong, affordable, and easily accessible. To improve the efficiency of lead-free (Au/CuSbS<sub>2</sub>/Cs<sub>2</sub>TiI<sub>x</sub>Br<sub>6-x</sub>/CdS/FTO) device structure, both linear and parabolic grading methods are used in the simulation. The perovskite composition Cs<sub>2</sub>TiI<sub>x</sub>Br<sub>6-x</sub> is a mixed halide system, with different amounts of iodine (I) and bromine (Br) ions integrated into the crystal lattice. Within the halide system, “x” indicates the percentage of iodide ions that replace bromide ions. Light absorption and energy conversion efficiency in solar cells may be maximized by fine tuning the material's band gap by varying “x,” which can range from 0 to 6. When the active layer is graded linearly, the band gap is adjusted by adjusting the composition <i>x</i>, which ranges from 0 to 6, throughout the active layer's thickness. The bending factor changes from 0 to 1 in the case of parabolic grading of the Cs<sub>2</sub>TiI<sub>x</sub>Br<sub>6-x</sub> layer, indicating an enhancement in the device's PCE as a result of high wavelength photon absorption. Our simulations show a significant improvement in PCE, with an astounding result of 31.18% for parabolic grading, a 7.93% increase above PCE from linear grading, which is 28.89%. Other noteworthy metrics that exhibit exceptional outcomes include J<sub>SC</sub> 34.36 mA.cm<sup>−2</sup>, FF 86.81%, and V<sub>OC</sub> 1.0452 V. The stability in the output of the device in the realistic temperature range confirms the highly stable nature of the proposed PSC device. These results show how effectively our approach improves the efficiency and effectiveness of Pb-free PSC's. As we are interested in this realistic environmental temperature range of the whole world, we proposed that Cs<sub>2</sub>TiI<sub>x</sub>Br<sub>6-x</sub>-based PSCs are highly suitable and stable for the real-time experiment, which is the need of PSCs nowadays.</p>\u0000 </div>","PeriodicalId":223,"journal":{"name":"Progress in Photovoltaics","volume":"33 5","pages":"599-615"},"PeriodicalIF":8.0,"publicationDate":"2025-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143762333","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Dynamic Solar Panel Orientation for Maximizing Efficiency Based on Trajectory of the Sun","authors":"Ali Bamshad, Maziar Kakavand","doi":"10.1002/pip.3893","DOIUrl":"https://doi.org/10.1002/pip.3893","url":null,"abstract":"<div>\u0000 \u0000 <p>The rapid expansion of photovoltaic technology is driven by a critical need for electricity and a growing emphasis on sustainable energy solutions. However, the primary challenge is that the efficiency of solar panels remains insufficient, making them less competitive compared to other energy sources in the long term. This inefficiency not only limits the overall power output but also discourages private investors due to slight benefit and low rate of return of investment. Consequently, many potential projects are stalled, as investors are hesitant to commit resources to technologies that do not promise adequate profitability. Additionally, low efficiency wastes the installation space, and the variability in solar energy generation further complicates the economic viability of solar investments. To tackle this issue, the objective of this research is to develop an innovative active-dynamic strategy aimed at enhancing the operational efficiency of solar panels through advanced Sun-tracking mechanisms. By integrating an ARM controller with a TSL2550 sensor module, our system orchestrates precise servomotor adjustments to optimize solar panel alignment based on the Sun's trajectory in both vertical and horizontal planes. Furthermore, employing state-of-the-art Micro-Python coding techniques significantly boosts power generation. Empirical data from practical deployments demonstrate a minimum fourfold increase in the overall efficiency of the solar energy system following the implementation of this strategy.</p>\u0000 </div>","PeriodicalId":223,"journal":{"name":"Progress in Photovoltaics","volume":"33 9","pages":"944-953"},"PeriodicalIF":7.6,"publicationDate":"2025-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145102335","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Quiterie Emery, Lea Dagault, Mark Khenkin, Nikoleta Kyranaki, Wander Max Bernardes de Araújo, Ulas Erdil, Matthias Demuylder, Stephane Cros, Rutger Schlatmann, Bernd Stannowski, Carolin Ulbrich
{"title":"Tips and Tricks for a Good Encapsulation for Perovskite-Based Solar Cells","authors":"Quiterie Emery, Lea Dagault, Mark Khenkin, Nikoleta Kyranaki, Wander Max Bernardes de Araújo, Ulas Erdil, Matthias Demuylder, Stephane Cros, Rutger Schlatmann, Bernd Stannowski, Carolin Ulbrich","doi":"10.1002/pip.3888","DOIUrl":"https://doi.org/10.1002/pip.3888","url":null,"abstract":"<p>Encapsulation is a critical topic to ensure the successful implementation of perovskite photovoltaics. Recently, vacuum lamination has been shown as a promising approach that combines compatibility with current industrial processes in conventional photovoltaic (PV) manufacturing and suitability to achieve good results with perovskites. Here, we explore some of the attractive encapsulation materials in terms of their ability to prevent moisture ingress, withstand elevated temperatures, and have suitable mechanical properties to avoid thermomechanical issues. We utilized the previously suggested concept of the “perovskite test,” an optical test with simple sample fabrication, for evaluating encapsulation quality and validated the findings with the full solar cell stack. Unsurprisingly, encapsulants without an edge sealant showed insufficient protection from moisture. Ionomer in combination with butyl edge seal showed the best barrier properties; however, this stack led to rapid delamination of the cell layers in thermal cycling tests. Configuration with only edge sealant does not have such an issue in principle (no mechanical stress applied), but an absence of the polymer in the stack is unfavorable in terms of optical design and sometimes showed perovskite degradation that we assign to trapped moisture in the butyl itself. Polyolefin with butyl edge sealant is not free of degradation but showed the most promising compromise by passing the damp heat test and showing fewer issues in the thermal cycling experiments. In general, our material study and optimization presented in this manuscript show that a holistic approach is needed when choosing an optimal encapsulation scheme for perovskite devices.</p>","PeriodicalId":223,"journal":{"name":"Progress in Photovoltaics","volume":"33 4","pages":"551-559"},"PeriodicalIF":8.0,"publicationDate":"2025-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/pip.3888","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143555190","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Photovoltaics Literature Survey (No. 196)","authors":"Ziv Hameiri","doi":"10.1002/pip.3886","DOIUrl":"https://doi.org/10.1002/pip.3886","url":null,"abstract":"","PeriodicalId":223,"journal":{"name":"Progress in Photovoltaics","volume":"33 2","pages":"372-377"},"PeriodicalIF":8.0,"publicationDate":"2025-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143110338","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kai Zhang, Oleksandr Mashkov, Muhammad Ainul Yaqin, Bernd Doll, Andreas Lambertz, Karsten Bittkau, Weiyuan Duan, Ian Marius Peters, Christoph J. Brabec, Uwe Rau, Kaining Ding
{"title":"Damp-Heat–Induced Degradation of Lightweight Silicon Heterojunction Solar Modules With Different Transparent Conductive Oxide Layers","authors":"Kai Zhang, Oleksandr Mashkov, Muhammad Ainul Yaqin, Bernd Doll, Andreas Lambertz, Karsten Bittkau, Weiyuan Duan, Ian Marius Peters, Christoph J. Brabec, Uwe Rau, Kaining Ding","doi":"10.1002/pip.3880","DOIUrl":"https://doi.org/10.1002/pip.3880","url":null,"abstract":"<p>Lightweight photovoltaic applications are essential for diversifying the solar energy supply. This opens up vast new scenarios for solar modules and significantly boosts the capacity of renewable energy. To ensure high efficiency and stability of the solar modules, several challenges need to be overcome. Degradation due to elevated temperature and/or humidity is a critical concern for silicon heterojunction (SHJ) solar modules. Here, we investigated the stability and degradation mechanism of encapsulated cells with lightweight configurations where the cells are based on three different types of transparent-conductive oxide (TCO): indium tin oxide (ITO), aluminum-doped zinc oxide (AZO), and a combination of ITO/AZO/ITO under humid and thermal environmental conditions. A damp heat (DH) test at a temperature of 85°C and relative humidity (RH) of 85% was performed on lightweight modules for 1000 h. Our results show that AZO is the most susceptible to DH degradation. The AZO film was damaged by the combined effects of moisture ingress and delamination of the interconnection foil, resulting in a decrease in the conductivity of the AZO film, leading to a dramatic increase in <i>R</i><sub>s</sub> and a decrease in <i>FF</i> of the modules. Consequently, moisture has a greater chance of percolating through the damaged AZO layer into the a-Si:H passivation layer, causing passivation degradation, which leads to an increase in recombination, resulting in a decrease in <i>V</i><sub>oc</sub> of the modules. In particular, after capping the AZO film with an ITO film, the efficiency loss of the ITO/AZO/ITO module was significantly reduced. This suggests that the ITO film could be a promising protective capping layer for the AZO-based solar cells.</p>","PeriodicalId":223,"journal":{"name":"Progress in Photovoltaics","volume":"33 4","pages":"541-550"},"PeriodicalIF":8.0,"publicationDate":"2025-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/pip.3880","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143555096","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}