Sonali Bhaduri, Makr Farkade, Rohan Bajhal, L. Kazmerski, S. Mallick, N. Shiradkar, A. Kottantharayil
{"title":"Cleaning efficacy of anti-soiling coatings","authors":"Sonali Bhaduri, Makr Farkade, Rohan Bajhal, L. Kazmerski, S. Mallick, N. Shiradkar, A. Kottantharayil","doi":"10.1109/PVSC45281.2020.9300697","DOIUrl":"https://doi.org/10.1109/PVSC45281.2020.9300697","url":null,"abstract":"Dust deposition on photovoltaic module can reduce energy generation up to 50% if not cleaned for 4 months in Mumbai, India (warm and humid climate). Hydrophobic (contact angle> 90°) anti-soiling coating (ASC) is a cost-effective mitigation strategy to reduce soiling. In this paper, we compared the cleaning efficacy of 4 different commercial hydrophobic anti-soiling coatings (on solar glass and PV modules) with a not-coated sample. All coated glass samples (A, B, C and D) showed higher cleaning efficacy (lower soiling loss) than the not-coated glass sample after cleaning with a 45 µl deionized water droplet. This was also confirmed by field exposure study done on PV modules (for coating B,C and D). Cleaning efficacy of the coating D (on PV module) decreased significantly after 2nd manual cleaning run, indicating abrasion caused by the cleaning tool, implying that the selection of cleaning methods/tools is critical. Under controlled environment (on solar glass) cleaning efficacy of all coated glass samples reduced by a factor of 6 (average) as the rolling water droplet travels from top to bottom, covering a total distance of 3.6 cm, This is due to the reduction in speed of the water droplet rolling off the surface as it accumulates more dust. Roll of angle for clean coated glass increases by a factor of 2 (for coating A,C and D) when measured on dust deposited glass substrate, indicating that roll-off angle depends on the surface of the ASC coatings, which may vary with exposure time and environmental conditions like soiling rate. Ranking of cleaning efficacy of ASC under field exposure correlated well with the roll-off angle measured on soiled samples in controlled experiments. This suggest roll - off angle as an important measure for the evaluation of the anti-soiling coatings.","PeriodicalId":6773,"journal":{"name":"2020 47th IEEE Photovoltaic Specialists Conference (PVSC)","volume":"14 1","pages":"0105-0108"},"PeriodicalIF":0.0,"publicationDate":"2020-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78868014","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Field Testing of Mars™ Soiling Sensor","authors":"M. Gostein, Ben Bourne, F. Farina, B. Stueve","doi":"10.1109/PVSC45281.2020.9300975","DOIUrl":"https://doi.org/10.1109/PVSC45281.2020.9300975","url":null,"abstract":"We report on an ongoing field evaluation of the Mars™ optical soiling sensor technology. The Mars™ soiling sensor was developed to provide a compact, low-cost, water-free and maintenance-free method to measure soiling at PV power plants, especially for small utility or commercial-scale sites where more complex solutions can be prohibitive. In this study, a Mars™ soiling sensor was deployed at a test site in California starting in February 2019. The site also includes a reference soiling measurement system employing a washed/unwashed PV reference cell pair. We review the correlation between the Mars™ and reference cell pair soiling results over a 13-month period.","PeriodicalId":6773,"journal":{"name":"2020 47th IEEE Photovoltaic Specialists Conference (PVSC)","volume":"87 1","pages":"0524-0527"},"PeriodicalIF":0.0,"publicationDate":"2020-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75985914","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Michael W. Hopwood, T. Gunda, H. Seigneur, Joseph Walters
{"title":"An assessment of the value of principal component analysis for photovoltaic IV trace classification of physically-induced failures","authors":"Michael W. Hopwood, T. Gunda, H. Seigneur, Joseph Walters","doi":"10.1109/PVSC45281.2020.9300601","DOIUrl":"https://doi.org/10.1109/PVSC45281.2020.9300601","url":null,"abstract":"Principal component analysis (PCA) reduces dimensionality by generating uncorrelated variables and improves the interpretability of the sample space. This analysis focused on assessing the value of PCA for improving the classification accuracy of failures within current-voltage (IV) traces. Our results show that combining PCA with random forests improves classification by only ∼1% (bringing the accuracy to >99%), compared to a baseline of only random forests (without PCA) of >98%. The inclusion of PCA, however, does provide an opportunity to study an interesting representation of all of the features on a single, two-dimensional feature space. A visualization of the first two principal components (similar to IV profile but rotated) captures how the inclusion of a current differential feature causes a notable separation between failure modes due to their effect on the slope. This work continues the discussion of generating different ways of extracting information from the IV curve, which can help with failure classification - especially for failures that only exhibit marginal profile changes in IV curves.","PeriodicalId":6773,"journal":{"name":"2020 47th IEEE Photovoltaic Specialists Conference (PVSC)","volume":"10 1","pages":"0798-0802"},"PeriodicalIF":0.0,"publicationDate":"2020-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87830239","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nicholas Theut, A. Jeffries, Rishi E. Kumar, G. von Gastrow, D. Fenning, M. Bertoni
{"title":"The Influence of Water Content on the Adhesion Between Solar Module Interfaces","authors":"Nicholas Theut, A. Jeffries, Rishi E. Kumar, G. von Gastrow, D. Fenning, M. Bertoni","doi":"10.1109/PVSC45281.2020.9300511","DOIUrl":"https://doi.org/10.1109/PVSC45281.2020.9300511","url":null,"abstract":"Delamination of solar module interfaces often occurs in field-tested solar modules after decades of service due to environmental stressors such as humidity. In the presence of water, the interfaces between encapsulant and the cell, glass, and backsheet all experience losses of adhesion, exposing the module to accelerated degradation. Understanding the relation between interfacial adhesion and water content inside PV modules can help mitigate detrimental power losses. Water content measurements via short wave infrared reflectometry combined with 180° peel tests were used to study peel test samples exposed to damp heat and dry heat conditions. The effect of temperature, cumulative water dose, and water content during peel tests on interfacial adhesion was studied. Temperature and time decreased adhesion at all interfaces, whereas water content at time of measurement showed significant decreases in strength for the backsheet/encapsulant interface. Water dose showed little effect for the glass/encapsulant and backsheet/encapsulant interfaces, but there was significant adhesion loss with water dose at the front cell busbar/encapsulant interface.","PeriodicalId":6773,"journal":{"name":"2020 47th IEEE Photovoltaic Specialists Conference (PVSC)","volume":"15 1","pages":"2057-2061"},"PeriodicalIF":0.0,"publicationDate":"2020-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87834702","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R. Cariou, R. Couderc, Yannick Roujol, A. Bidaud, F. Chabuel
{"title":"Light and Dark IV Measurements Correlations for Space Solar Array Failure Detection in Stowed Configuration","authors":"R. Cariou, R. Couderc, Yannick Roujol, A. Bidaud, F. Chabuel","doi":"10.1109/PVSC45281.2020.9300966","DOIUrl":"https://doi.org/10.1109/PVSC45281.2020.9300966","url":null,"abstract":"Performance control steps during manufacturing and/or handling of space solar array can consume time and money. For instance the measurement under AM0 spectrum of a III-V photovoltaic array (PVA) performance (e.g. in production line, during satellite integration tests, etc.) requires complex, large and precise equipment. In this study, we evaluate the possibility to replace the LIV by DIV control step during PVA manufacturing / handling sequence. We investigate the correlations between light IV (LIV), dark IV (DIV) and electroluminescence (EL) characterizations on PVA breadboards composed of Si or III-V multi-junction solar cells. Controlled impact cycles are performed on PVA breadboards, and light/dark IV performance degradations are monitored.","PeriodicalId":6773,"journal":{"name":"2020 47th IEEE Photovoltaic Specialists Conference (PVSC)","volume":"44 1","pages":"1665-1667"},"PeriodicalIF":0.0,"publicationDate":"2020-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87883008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Study of Models Combination for Global Clear Sky Irradiance Models","authors":"Xixi Sun, Xiaoyi Yang, Peifeng Wang","doi":"10.1109/PVSC45281.2020.9301026","DOIUrl":"https://doi.org/10.1109/PVSC45281.2020.9301026","url":null,"abstract":"Clear sky global horizontal irradiance (GHIcs) defines the theoretical maximum irradiance reaching a horizontal surface and are often derived from semi-empirical or physical based clear-sky models. In this study we demonstrate a naive model combination method of global clear sky models for improved estimation of GHIcs. To be specific, 10 best performing beam and diffuse clear sky models are each selected from pervious study [1] and are paired to create 97 combinations of global clear-sky models. By including 18 standalone global clear sky models (distinguish from individual beam and diffuse combined models), this study compares 115 global clear sky models under 100 worldwide solar measurement ground stations. After rigorous data quality control and clear sky detection, 18.7 million 1-min time data points (between 2015-01-01 and 2019-09-30) are used to evaluate all 115 models. Principal Component Analysis (PCA) ranking procedure is then employed to aggregate 12 error metrics and provides the overall ranking scores. The top 3 world-wide performing global clear-sky models are MMAC-v1_IQBAL-C, MMAC-v2_PSIREST and REST2-v5, i.e., not the combination of the best beam and diffuse models. Such results may be due to the over- or under- estimation of different beam and diffuse models. Another interesting finding is the REST2-v5 model which was also listed in the top 10 global clear sky models in previous study. In all, most combined models achieve greater performance (higher PCA ranking scores) than the original ones.","PeriodicalId":6773,"journal":{"name":"2020 47th IEEE Photovoltaic Specialists Conference (PVSC)","volume":"2 1","pages":"0724-0728"},"PeriodicalIF":0.0,"publicationDate":"2020-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87112964","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Enhanced the crystallinity of Cu(In, Ga)Se2via an improved silver-treated process","authors":"Zhaojing Hu, Yunxiang Zhang, Chaojie Wang, Zhi-qiang Zhou, Yun Sun, Wei Liu","doi":"10.1109/PVSC45281.2020.9300575","DOIUrl":"https://doi.org/10.1109/PVSC45281.2020.9300575","url":null,"abstract":"As we know, the quality of the CIGS film is important for the improvement of device performance: an improved crystallization can reduce the bulk recombination of the absorber layer. In this work, different silver (Ag) treatment processes are employed to improve the CIGS film quality after three-stage deposition process. We find that the grain size and crystallinity of CIGS films are considerably enhanced by increasing the deposition temperature and annealing time. The growth mechanisms of Ag treatment process could be visually displayed by the new reaction models of Ag treatment process. According to the XRD results, we have demonstrated that the element Ag contributes to the (112) preferred orientation of the absorber layer, which has the lower surface energy compared with (220)/(204) preferred orientation of CIGS film. With appropriate Ag-treated process, both electrical and optical properties of device are enhanced. And the best Ag-treated CIGS solar cell with the conversion efficiency of about 17.1% has a relative increase of about 11.8% in contrast with that of the reference CIGS solar cell.","PeriodicalId":6773,"journal":{"name":"2020 47th IEEE Photovoltaic Specialists Conference (PVSC)","volume":"81 1 1","pages":"2667-2670"},"PeriodicalIF":0.0,"publicationDate":"2020-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87996627","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
T. Kodalle, Hasan A. Yetkin, T. Bertram, R. Schlatmann, C. Kaufmann
{"title":"Setting up a Device Model for Rb-Conditioned Chalcopyrite Solar Cells","authors":"T. Kodalle, Hasan A. Yetkin, T. Bertram, R. Schlatmann, C. Kaufmann","doi":"10.1109/PVSC45281.2020.9301015","DOIUrl":"https://doi.org/10.1109/PVSC45281.2020.9301015","url":null,"abstract":"A comprehensive device model based on SCAPS-1D simulations is presented that reproduces the experimentally determined current-voltage and capacitance-voltage characteristics of a Rb-free reference, a sample that underwent an RbF-treatment, and a sample based on a CIGSe/RbInSe2-stack. According to this model, and in agreement with experimental findings, the main consequences of both Rb-conditionings are an increased doping-density and a defect passivation in the CIGSe as well as the formation of a photocurrent-barrier at the hetero-interface. With the numerical model established, fundamental aspects of the Rb-conditioning, as e.g. the differentiation between its effect on bulk and interface recombination are discussed.","PeriodicalId":6773,"journal":{"name":"2020 47th IEEE Photovoltaic Specialists Conference (PVSC)","volume":"34 1","pages":"1156-1162"},"PeriodicalIF":0.0,"publicationDate":"2020-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88048994","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Temperature Effects on DC Cable Voltage Drop in Utility Scale Rooftop Solar PV Plant Based on Empirical Model","authors":"A. Desai, Vansh Pandya, I. Mukhopadhyay, A. Ray","doi":"10.1109/PVSC45281.2020.9300709","DOIUrl":"https://doi.org/10.1109/PVSC45281.2020.9300709","url":null,"abstract":"This paper discusses the effect of losses occurred due to rise in temperature in determining the optimal capacity of DC cable for a Solar Photovoltaic (PV) system application. An optimization is considered to address the existing trade-off between cost of losses due to the voltage drop and its investment cost. The main outcome of the model is the optimal DC cable capacity for a given PV system, as well as the relevant optimal DC cable sizing with respect to voltage drop. An experimental result of 250 kW Solar PV system installed at a latitude of 23.029° N and longitude of 72.577°E is used to determine the effect of temperature rise on voltage drop of dc cable at outdoor conditions. This paper presents an empirical model to determine the effect of voltage drop by temperature through experimental data. In this work a focus is made on th effect of temperature on DC cable and its solution towards performance guarantee as well as improvement in generation forecasting. This study is carried out to find on site dc voltage prediction with minimum error and provides prediction based on empirical formula. The model results reveal that, by installing the dc cable in outdoor conditions of semi-arid places like Gujarat, and other arid regions, where average ambient temperature is about 30°C- 35°C and in summer maximum is above 40°C and there is an increment in voltage drop of about 12 to 18 % with respect to standard test condition. By choosing the proper cable size we can save 2400 kWh to 5400 kWh annually which reduces annually 1200kg to 3000 Kg Co2 and 300Kg to 700 Kg coal could be prevented annually. With optimal design of DC cable we can reduced the cable loss below 1 % which is at par and it generates 1.8 to 2.4 times more revenue.","PeriodicalId":6773,"journal":{"name":"2020 47th IEEE Photovoltaic Specialists Conference (PVSC)","volume":"116 1","pages":"2397-2402"},"PeriodicalIF":0.0,"publicationDate":"2020-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86077888","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Clustering Based Optimization and Automation of Utility Scale Solar Site Design","authors":"K. Rhee","doi":"10.1109/PVSC45281.2020.9300981","DOIUrl":"https://doi.org/10.1109/PVSC45281.2020.9300981","url":null,"abstract":"EDFR has developed a series of methods for quickly drafting a set of utility scale photovoltaic plant layouts and choosing an optimized plant design from that set. The automated drafting methodology utilizes a standard clustering technique and a novel cluster equalizing post-processing algorithm to solve a problem in existing automated drafting software, which is that existing techniques cannot assign dc power in the form of trackers to inverters without human intervention. This step is crucial to create end to end automation of a PV plant layout. Without it, it is impossible to accurately determine the layout of dc wiring and associated electrical equipment. The work nearly eliminates the need for developer drafting of utility scale photovoltaic plant layouts and provides a foundation for reducing levelized cost of energy by allowing EDFR to select the most financially optimal project design without investing large amounts of time creating the feasibility space under which optimization can occur. (Abstract)","PeriodicalId":6773,"journal":{"name":"2020 47th IEEE Photovoltaic Specialists Conference (PVSC)","volume":"126 1","pages":"0021-0024"},"PeriodicalIF":0.0,"publicationDate":"2020-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82907656","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}