scholarly journals Electroluminescence Test to Investigate the Humidity Effect on Solar Cells Operation

Energies ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 2659 ◽  
Author(s):  
Daniela Fontani ◽  
Paola Sansoni ◽  
Franco Francini ◽  
Matteo Messeri ◽  
Giacomo Pierucci ◽  
...  

The electroluminescence test is an experiment typically used to verify the behavior of the photovoltaic cell and to qualitatively check its integrity. It works by operating the photovoltaic cell as a diode polarized directly: the cells that light up in a module indicate how many of them work. This test provides an estimate of the maximum performance of the entire photovoltaic module. A qualitative inspection was performed by electroluminescence tests on 48 modules of photovoltaic cells. They had already been installed on a small-size concentration solar plant before the test and some modules had reached a lower level of performance than expected. A first electroluminescence test was performed, which showed that only 61.5% of the photocells worked. Since there were visible signs of humidity within the various modules, some of the inoperative modules underwent a dehumidification treatment in a climatic chamber. A second electroluminescence test showed that the percentage of functioning cells had increased to 66.3% after the drying treatment.

Modeling and simulation of photovoltaic cells or PV cell is becoming important as it provides an easy platform to perform studies on photovoltaic cells and the design and analysis of the system based on photovoltaic cells. In this paper, we present our study of the ordinary photovoltaic module on the basis of one diode and two diode models. Studies are extended to solar cells as solar cells are similar to photodiodes. Performance of the solar cells may be described in terms of ideality factor (α), which decreases with temperature and is observed to affect the performance of the PV cell. PV systems exhibit better performance with diodes having higher values for α. In this paper, our efforts are to study the effects of α on Current and Power versus Voltage characteristics of the solar cells. MATLAB simulation of solar cell systems is a simple and elegant mechanism useful for designing and modeling the framework of the solar power plant


Coatings ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 329 ◽  
Author(s):  
Dong Shin ◽  
Suk-Ho Choi

It is necessary to develop semitransparent photovoltaic cell for increasing the energy density from sunlight, useful for harvesting solar energy through the windows and roofs of buildings and vehicles. Current semitransparent photovoltaics are mostly based on Si, but it is difficult to adjust the color transmitted through Si cells intrinsically for enhancing the visual comfort for human. Recent intensive studies on translucent polymer- and perovskite-based photovoltaic cells offer considerable opportunities to escape from Si-oriented photovoltaics because their electrical and optical properties can be easily controlled by adjusting the material composition. Here, we review recent progress in materials fabrication, design of cell structure, and device engineering/characterization for high-performance/semitransparent organic and perovskite solar cells, and discuss major problems to overcome for commercialization of these solar cells.


2020 ◽  
Author(s):  
Naoufel Ben Hamadi

Abstract Background: A photovoltaic cell, or solar cell, is an electronic component which, exposed to light, produces electricity thanks to the photovoltaic effect. Organic photovoltaic cells are photovoltaic cells of which at least the active layer consists of organic molecules. It has a yield of at least 15%. The future prospects of the research for solar cells application has required for the development in the field.Main body: Dye-sensitized solar cells are considered to be promising candidates for low-cost solar energy harvesting using sustainable and environmentally friendly materials. In general, solar cells sensitized to dyes consist of three parts: TiO2 sensitized to the photoanode dye with porous film on a transparent conductive glass, an electrolyte solution penetrating through the TiO2 anode film, and the conductive oxide transparent platinum glass as counter electrode.Conclusion: In this work, betanin dye was extracted from mature red fruits of Opuntia ficus indica and purified with fractional crystallization protocol using an 8:2 (v/v) ratio of ethyl acetate/ethanol. TiO2_films with different thickness values have been prepared CV and US sensitization of TiO2_films using betanin dye prove an enhancement on the uniformity distribution of the dye on the film in case of US method. Emission spectra of Dye_TiO2 films have been measured and show a hyperchromic shift of the emission intensity with the increase of the thickness due to the augmentation of betanin content. A comparison between the photovoltaic properties of prepared betanin_DSSC and N719 dye_DSSC reveals that betanin dye could be successfully proposed as a sensitizing dye in solar cell applications.


Author(s):  
A. S. Tonkoshkur ◽  
A. V. Ivanchenko

One of the main problems in ensuring the reliability of solar electrical power sources is local overheating, when hot spots form in photovoltaic cells of solar arrays. It is currently considered that these negative phenomena are caused, among other things, by overvoltage in the electrical circuits of solar arrays. This leads to the appearance of defective elements and a significant decrease in the functionality of the entire power generation system up to its complete failure. This study considers the possible ways to increase the reliability of solar arrays by using thermistor thermocontacting layers for preventing overvoltage events and overheating. The authors use simulation to study electrical characteristics of a photovoltaic cell in thermal contact with an additional layer based on thermistor materials with a metal to semiconductor phase transition. Vanadium dioxide with a phase transition temperature of ~340 K is considered to be a promising material for this purpose. During the phase transition, electrical resistance sharply decreases from the values characteristic of dielectrics to the values associated with metal conductors. It is shown that such thermistor layers can be used for protecting solar cells from electrical overheating under the following basic conditions: — the layer’s resistance in the «cold» state significantly exceeds that of the lightened forward-biased solar cell; — the layer’s resistance in the «heated» state is sufficiently low compared to those of the reverse-biased photovoltaic cell and of the power source. The current and temperature of the reverse-biased photovoltaic cell are limited and stabilized, and the voltage drop sharply decreases from the moment when the temperature of the thermistor layer reaches the values close to the temperature of its transition to the low-conductivity state. The obtained results substantiate the potntial of the described approach to protect photovoltaic cells of solar modules against electric thermal overloads.


2021 ◽  
Author(s):  
Alexander Tonkoshkur ◽  
Alexander Ivanchenko ◽  
Liliya Nakashydze ◽  
Alexander Lyashkov ◽  
Igor Gomilko

The experience of operating solar arrays indicates the need to solve the problem of creating effective and reliable switching elements to block defective and damaged photovoltaic cells. Available methods of solving this problem (for example, the use of transistor switches, electronic systems, etc.) either do not completely solve it, or are expensive. The tasks of increasing the reliability and efficiency of switching elements, preventing the destruction of photovoltaic cells which occurs during heating by dark current ("hot spots" and fire hazardous situations) are relevant. Recently, one of the promising solutions of this problem is the use of additional devices for isolating inactive (shaded or defective) areas of both separate photovoltaic cells and their modules. These devices are PPTC (polymeric positive temperature coefficient) resettable fuses of PolySwitch type, which are polymer composites with nanoscale carbon fillers. The basic functional property of PPTC fuse is an abrupt increase in electrical resistance by several orders of magnitude when a temperature is reached and a return to the initial high conductive state when the temperature drops. The advantages of such structures based on polymer composites with nanocarbon fillers include: – close to the metal resistance to the switching temperature and to the resistance of the insulator above the specified temperature; – possibility of realization in the form of discrete elements and continuous film-tapes (that is important at the decision of problems of realization of isolation of defective local area of the separate photovoltaic cell); – reaction in the form of temporary isolation of separate components of the solar array to increase their temperature. The research results are presented and the concept of overload protection by using resettable fuses based on polymer nanocomposite materials with nanocarbon fillers is substantiated in this paper. In particular, the expediency of series connection of PolySwitch fuses to photovoltaic modules with parallel connection of their strings is shown to prevent an abnormal situation, namely, a complete loss of electrical energy generated by such a string, which can occur when one of its modules is short-circuited. The circuit solutions in the form of combined structure based on layers of a varistor ceramics and a posistor polymer nanocomposite with carbon filler being in thermal contact are investigated. The prospect of its use to protect photovoltaic cells with a high reverse resistance from overvoltage is established. The problem of protection against local overheating in photovoltaic cells (or their parallel connections) by physical and technological methods, in particular, by creating photovoltaic cells with a built-in layer based on a posistor composite being in thermal contact with it, is analyzed. In general, the described results represent a new direction in the field of improving photovoltaic systems, in particular, in terms of increasing their efficiency, operating time and reliability by using solid-state devices based on polymer posistor nanocomposites and varistor ceramics as means of their protection from electrical and thermal overloads. Keywords: SOLAR ARRAY, PHOTOVOLTAIC MODULE, PHOTOVOLTAIC CELL, ELECTRIC OVERLOAD, POLYMER POSISTOR NANOCOMPOSITE, HOT SPOT, VARISTOR CERAMICS


2020 ◽  
Vol 10 ◽  
Author(s):  
Naoufel Ben Hamadi

Background: A photovoltaic cell, or solar cell, is an electronic component which, exposed to light, produces electricity thanks to the photovoltaic effect. Organic photovoltaic cells are photovoltaic cells of which at least the active layer consists of organic molecules. It has a yield of at least 15%. The future prospects of the research for solar cells application has required for the development in the field. Objectives: In this work, we propose in this paper to study the potential of purified betanin dye on the DSSC applications. Methods: Extraction was elaborated under sonication conditions (25 kHz, 100 W) for 15 minutes. Various films of TiO2 with different thickness were prepared referring to doctor blade method on a FTO glass substrate. Results: The increase of the thickness value of dye_TiO2 films induces a hyperchromic shift of the emission intensity. Conclusion: In this work, betanin dye was extracted from mature red fruits of Opuntia ficus indica and purified with fractional crystallization protocol using an 8:2 (v/v) ratio of ethyl acetate/ethanol. TiO2_films with different thickness values have been prepared CV and US sensitization of TiO2_films using betanin dye prove an enhancement on the uniformity distribution of the dye on the film in case of US method. Emission spectra of Dye_TiO2 films have been measured and show a hyperchromic shift of the emission intensity with the increase of the thickness due to the augmentation of betanin content. A comparison between the photovoltaic properties of prepared betanin_DSSC and N719 dye_DSSC reveals that betanin dye could be successfully proposed as a sensitizing dye in solar cell applications.


2020 ◽  
Vol 4 (41) ◽  
pp. 51-56
Author(s):  
DMITRIY STREBKOV ◽  
◽  
NATAL’YA FILIPPCHENKOVA ◽  

In the field of energy supply to agro-industrial facilities, there is an increasing interest in the development of structures and engineering systems using renewable energy sources, including solar concentrator thermal and photovoltaic modules that combine photovoltaic modules and solar collectors in one structure. The use of the technology of concentrator heat and photovoltaic modules makes it possible to increase the electrical performance of solar cells by cooling them during operation, and significantly reduces the need for centralized electricity and heat supply to enterprises of the agroindustrial complex. (Research purpose) The research purpose is in numerical modeling of thermal processes occurring in a solar concentrator heat-photovoltaic module. (Materials and methods) Authors used analytical methods for mathematical modeling of a solar concentrator heat and photovoltaic module. Authors implemented a mathematical model of a solar concentrator heat and photovoltaic module in the ANSYS Fluent computer program. The distribution contours of temperature and pressure of the coolant in the module channel were obtained for different values of the coolant flow rate at the inlet. The verification of the developed model of the module on the basis of data obtained in an analytical way has been performed. (Results and discussion) The results of comparing the calculated data with the results of computer modeling show a high convergence of the information obtained with the use of a computer model, the relative error is within acceptable limits. (Conclusions) The developed design of the solar concentrator heat and photovoltaic module provides effective cooling of photovoltaic cells (the temperature of photovoltaic cells is in the operating range) with a module service life of at least twenty-five years. The use of a louvered heliostat in the developed design of a solar concentrator heat and photovoltaic module can double the performance of the concentrator.


Author(s):  
Gabriela Lewinska ◽  
Jerzy Sanetra ◽  
Konstanty W. Marszalek

AbstractAmong many chemical compounds synthesized for third-generation photovoltaic applications, quinoline derivatives have recently gained popularity. This work reviews the latest developments in the quinoline derivatives (metal complexes) for applications in the photovoltaic cells. Their properties for photovoltaic applications are detailed: absorption spectra, energy levels, and other achievements presented by the authors. We have also outlined various methods for testing the compounds for application. Finally, we present the implementation of quinoline derivatives in photovoltaic cells. Their architecture and design are described, and also, the performance for polymer solar cells and dye-synthesized solar cells was highlighted. We have described their performance and characteristics. We have also pointed out other, non-photovoltaic applications for quinoline derivatives. It has been demonstrated and described that quinoline derivatives are good materials for the emission layer of organic light-emitting diodes (OLEDs) and are also used in transistors. The compounds are also being considered as materials for biomedical applications.


2021 ◽  
Vol 13 (11) ◽  
pp. 6364
Author(s):  
June Raymond L. Mariano ◽  
Yun-Chuan Lin ◽  
Mingyu Liao ◽  
Herchang Ay

Photovoltaic (PV) systems directly convert solar energy into electricity and researchers are taking into consideration the design of photovoltaic cell interconnections to form a photovoltaic module that maximizes solar irradiance. The purpose of this study is to evaluate the cell spacing effect of light diffusion on output power. In this work, the light absorption of solar PV cells in a module with three different cell spacings was studied. An optical engineering software program was used to analyze the reflecting light on the backsheet of the solar PV module towards the solar cell with varied internal cell spacing of 2 mm, 5 mm, and 8 mm. Then, assessments were performed under standard test conditions to investigate the power output of the PV modules. The results of the study show that the module with an internal cell spacing of 8 mm generated more power than 5 mm and 2 mm. Conversely, internal cell spacing from 2 mm to 5 mm revealed a greater increase of power output on the solar PV module compared to 5 mm to 8 mm. Furthermore, based on the simulation and experiment, internal cell spacing variation showed that the power output of a solar PV module can increase its potential to produce more power from the diffuse reflectance of light.


2014 ◽  
Vol 59 (1) ◽  
pp. 247-252 ◽  
Author(s):  
M. Musztyfaga-Staszuk ◽  
L.A. Dobrzanski ◽  
S. Rusz ◽  
M. Staszuk

Abstract The aim of the paper was to apply the newly developed instruments ‘Corescan’ and ‘Sherescan’ in order to measure the essential parameters of producing solar cells in comparison with the standard techniques. The standard technique named the Transmission Line Method (TLM) is one way to monitor contacting process to measure contact resistance locally between the substrate and metallization. Nowadays, contact resistance is measured over the whole photovoltaic cell using Corescanner instrument. The Sherescan device in comparison with standard devices gives a possibility to measure the sheet resistance of the emitter of silicon wafers and determine of both P/N recognition and metal resistance. The Screen Printing (SP) method is the most widely used contact formation technique for commercial silicon solar cells. The contact resistance of manufactured front metallization depends of both the paste composition and co-firing conditions. Screen printed front side metallization and next to co-fired in the infrared conveyor furnace was carried out at various temperature from 770°C to 920°C. The silver paste used in the present paper is commercial. The investigations were carried out on monocrystalline silicon wafers. The topography of co-fired in the infrared belt furnace front metallization was investigated using the atomic force microscope and scanning electron microscope (SEM). There were researched also cross sections of front contacts using SEM microscope. Front contacts of the solar cells were formed on non-textured silicon surface with coated antireflection layer. On one hand, based on electrical properties investigations using Sherescan instrument it was obtained the knowledge of the emitter sheet resistance across the surface of a wafer, what is essential in optimizing the emitter diffusion process. On the other hand, it was found using Corescan instrument that the higher temperature apparently results in a strongly decreased contact resistance.


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