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Outdoor Performance Characterization of Multi-Crystalline Silicon Solar Module  [PDF]
S. Parthasarathy,P. Neelamegam,P. Thilakan
Journal of Applied Sciences , 2012,
Abstract: The performance parameters of solar modules are characterized under Standard Test Conditions (STC). However, solar modules when deployed outdoor results in the output that differs from its output obtained at STC, due to the influence of various environmental factors, leading to confusion in deciding the appropriate electrical components and loads used for Solar Photovoltaic (SPV) power plant. In view of the above, Outdoor performance characterization of the multi-crystalline silicon solar module was studied. Daily solar illumination data were measured using an optical Pyranometer and analyzed together with the module output power. Blow of air mass was found very active at the site. Stable voltage output and dynamic current outputs were recorded. The average module efficiency of ~10 and 9.5% were obtained for the high and low illumination days, respectively. However, the integrated daily efficiency was found as 9.8% irrespective of the variation in solar illumination. Percentage of variations between the solar illumination and its associated current output under the blow of air mass were not found matching. Higher blow of air mass and its associated reduction in the solar insolation condition found yielding higher current output than the expected.
Comparison of Electrical and Thermal Performances of Glazed and Unglazed PVT Collectors  [PDF]
Jin-Hee Kim,Jun-Tae Kim
International Journal of Photoenergy , 2012, DOI: 10.1155/2012/957847
Abstract: Photovoltaic-thermal (PVT) collectors combine photovoltaic modules and solar thermal collectors, forming a single device that receives solar radiation and produces electricity and heat simultaneously. PVT collectors can produce more energy per unit surface area than side-by-side PV modules and solar thermal collectors. There are two types of liquid-type flat-plate PVT collectors, depending on the existence of glass cover over PV module: glass-covered (glazed) PVT collectors, which produce relatively more thermal energy but have lower electrical yield, and uncovered (unglazed) PVT collectors, which have relatively lower thermal energy with somewhat higher electrical performance. In this paper, the experimental performance of two types of liquid-type PVT collectors, glazed and unglazed, was analyzed. The electrical and thermal performances of the PVT collectors were measured in outdoor conditions, and the results were compared. The results show that the thermal efficiency of the glazed PVT collector is higher than that of the unglazed PVT collector, but the unglazed collector had higher electrical efficiency than the glazed collector. The overall energy performance of the collectors was compared by combining the values of the average thermal and electrical efficiency. 1. Introduction The overall efficiency of a PV system, which has relatively lower efficiency among renewable energy systems, depends on the efficiency of the solar cells and the PV modules themselves. Today, in general, silicon-based PV modules have an electrical efficiency of about 12~16% under standard test condition (STC: air mass 1.5, irradiation intensity 1000?W/m2, and cell temperature 25°C). Furthermore, the efficiency of PV modules of a Building-Integrated Photovoltaic (BIPV) System can be lowered due to the increase of the PV module temperature. The photovoltaic/thermal (PVT) concept offers an opportunity to increase overall efficiency by the use of waste heat generated in the PV module of the BIPV system. It is well known that PVT systems enhance PV efficiency by PV cooling, where PV cooling may be achieved by circulating a colder fluid, water, or air, at the underside of the PV module. Among the various types of PVT systems, liquid-type PVT collectors combine a photovoltaic module and a solar thermal collector, forming a single device that converts solar energy into electricity and heat simultaneously. The heat from PV modules can be removed in order to enhance the electrical performance of the PV module; this heat can be converted into useful thermal energy. As a result, PVT
Monocrystalline silicon solar cells applied in photovoltaic system
L.A. Dobrzański,A. Dryga?a,M. Giedro?,M. Macek
Journal of Achievements in Materials and Manufacturing Engineering , 2012,
Abstract: Purpose: The aim of the paper is to fabricate the monocrystalline silicon solar cells using the conventional technology by means of screen printing process and to make of them photovoltaic system.Design/methodology/approach: The investigation of current – voltage characteristic to determinate basic electrical properties of monocrystalline silicon solar cells were investigated under Standard Test Condition. Photovoltaic module was produced from solar cells with the largest short-circuit current, which were joined in series.Findings: This work presents a conventional technological process by means of screen printed method of monocrystalline silicon solar cells production. In order to obtain a device producing an electrical energy, solar cells were connected in a photovoltaic module. Then protected from damages by Schottky and Zener diodes.Practical implications: The module was used to build a demonstration photovoltaic system – traffic light - pedestrian crossing, which shows the practical use of widely available, renewable energy source which is the Sun.Originality/value: The key to solve ecological problems, which are effects of mass combustion of fossil fuel such as: coal and crude oil is development of renewable energy technology like photovoltaic energy.
Modelling Study of Magnetic Field Effect on the Performance of a Silicon Photovoltaic Module  [PDF]
Dioari Ulrich Combari, Issa Zerbo, Martial Zoungrana, Emmanuel Wendsongre Ramde, Dieudonné Joseph Bathiebo
Energy and Power Engineering (EPE) , 2017, DOI: 10.4236/epe.2017.98028
Abstract: Solar Photovoltaic is a very promising solution that can greatly contribute in solving the increasing global energy demand. In both rural and urban areas, photovoltaic modules are in some instances installed close to telecommunication antennas or voltage transformers which generate important magnetic fields in their vicinity. The question is whether or not these magnetic fields affect the performances of the photovoltaic installations. This article presents a modelling study of external magnetic field effect on the electrical parameters of a photovoltaic module. The photocurrent, the photovoltage, the electric power, the series and the shunt resistances of the photovoltaic module, made up of ideal cells, are deduced from those of a silicon solar cell. Then, the I-V and P-V curves are plotted and the theoretical values of the electrical parameters of the photovoltaic module are deduced. The series and shunt resistances of the photovoltaic module are calculated using well known equations and the previous electrical parameters. The results show the negative effect of magnetic field on the performance of a solar photovoltaic module.
Application of crystalline silicon solar cells in photovoltaic modules  [PDF]
L.A. Dobrzański,A. Dryga?a,M. Giedro?
Archives of Materials Science and Engineering , 2010,
Abstract: Purpose: The aim of the paper is to determinate basic electrical properties of solar cells, made of them photovoltaic module and analysis of its main electrical parameters.Design/methodology/approach: In this study, several methods were used: current – voltage characteristic to determinate basic electrical properties of 36 monocrystalline silicon solar cells, soft soldering technique to bond solar cells . Photovoltaic module was produced from 31 solar cells with the largest short-circuit current, which were joined in series.Findings: In order to obtain a device producing an electrical current with a higher current and voltage level, solar cells were connected in a photovoltaic module and then protected from damages derived from external factors. In series connection solar cell with the lowest current determines the current flowing in the PV module. Taking this fact into account the analysis of photovoltaic module construction was performed.Practical implications: Because of low operating cost and simplicity of photovoltaic installation, photovoltaic technology is perfectly suitable for supplying objects which are beyond powers network range as well as connected to it. In many cases, they are less costly option than a direct extension of the power network.Originality/value: Protecting the environment from degradation due to pollution, which has source in conventional power industry, as well as diminishing resources of fossil fuels, tend to increase development of renewable energy production such as photovoltaic technology.
Electrical Control of Silicon Photonic Crystal Cavity by Graphene  [PDF]
Arka Majumdar,Jonghwan Kim,Jelena Vuckovic,Feng Wang
Physics , 2012, DOI: 10.1021/nl3039212
Abstract: Efficient conversion of electrical signal to optical signal in nano-photonics enables solid state integration of electronics and photonics. Combination of graphene with photonic crystals is promising for electro-optic modulation. In this paper, we demonstrate that by electrostatic gating a single layer of graphene on top of a photonic crystal cavity, the cavity resonance can be changed significantly. A ~2nm change in the cavity resonance linewidth and almost 400% (6 dB) change in resonance reflectivity is observed. In addition, our analysis shows that a graphene-photonic crystal device can potentially be useful for a high speed, and low power absorptive and refractive modulator, while maintaining a small physical footprint.
Investigations on the Outdoor Performance Characteristics of Multicrystalline Silicon Solar Cell and Module  [PDF]
Sivakumar Parthasarathy,P. Neelamegam,P. Thilakan,N. Tamilselvan
Conference Papers in Science , 2013, DOI: 10.1155/2013/838536
Abstract: Multicrystalline silicon solar cell and its module with 18 cells connected in series were mounted on an inclined rack tilted 12° South positioned at latitude of 12.0107° and longitude of 79.856°. Corresponding solar irradiance was measured using an optical Pyranometer. Measured irradiance, open circuit voltage ( ), and short circuit current ( ) values were analyzed. values of both the cell and module were found saturated at above the critical value of illuminations which were different from each other. The integrated daily efficiency for the cell and module were ~10.25% and ~9.39%, respectively, that were less than their respective standard test condition’s value. The reasons for this drop in efficiencies were investigated and reported. 1. Introduction Uncertainty in the prediction of the performance of solar photovoltaic power systems (SPVPSs) is a major hindering fact that suppresses its utility. This uncertain output performance of SPVPS is due to the exposure of unpredictable solar irradiances that is found varying with the location [1]. Numerous approaches were made to overcome the hindering fact, but so far, all of them are unsuccessful [1–5]. In general, photovoltaic (PV) modules are rated at indoor standard test conditions (STCs) using the irradiance of 1000?W/m2 and the temperature of 25°C [5]. However, the outdoor conditions do not follow the STC values and are found variable in nature due to the change in the position of sun and environmentally interference factors to the solar radiation such as the geographical location, cloud pattern, and blow of air mass [6]. It is reported that the seasonal variations shifts the spectral profile [7] and emboss variations in the spectrum & light intensity, reflection of unpolarized light, polarization and the temperature [4, 8–10]. Since, the solar illumination serves as the input to the SPVPS operation, any variation in the solar illumination results in a profound output changes. Hence, it is required to use output optimization devices such as DC/DC converter and the maximum power point tracker (MPPT) with due considerations on the characteristics of add on devices such as charge controller, battery, and inverter [11, 12]. It was demonstrated that the sizing of PV inverter is greatly influenced by site-dependent peculiarities like ambient temperature and solar irradiation distribution characteristics [12]. In addition, performance of PV module based on tilt angle and various mounting conditions are analyzed by [13, 14], and it was found that the outdoor weather conditions along with the tilt angle and its
Impacts of Post-metallisation Processes on the Electrical and Photovoltaic Properties of Si Quantum Dot Solar Cells  [cached]
Di Dawei,Perez-Wurfl Ivan,Gentle Angus,Kim Dong-Ho
Nanoscale Research Letters , 2010,
Abstract: As an important step towards the realisation of silicon-based tandem solar cells using silicon quantum dots embedded in a silicon dioxide (SiO2) matrix, single-junction silicon quantum dot (Si QD) solar cells on quartz substrates have been fabricated. The total thickness of the solar cell material is 420 nm. The cells contain 4 nm diameter Si quantum dots. The impacts of post-metallisation treatments such as phosphoric acid (H3PO4) etching, nitrogen (N2) gas anneal and forming gas (Ar: H2) anneal on the cells’ electrical and photovoltaic properties are investigated. The Si QD solar cells studied in this work have achieved an open circuit voltage of 410 mV after various processes. Parameters extracted from dark I–V, light I–V and circular transfer length measurement (CTLM) suggest limiting mechanism in the Si QD solar cell operation and possible approaches for further improvement.
Electrical Performance Study of a Large Area Multicrystalline Silicon Solar Cell Using a Current Shunt and a Micropotentiometer  [PDF]
Hala Mohamed Abdel Mageed, Ahmed Faheem Zobaa, Ahmed Ghitas, Mohamed Helmy Abdel Raouf, Mohamed Sabry, Abla Hosni Abd El-Rahman, Mohamed Mamdouh Abdel Aziz
Engineering (ENG) , 2010, DOI: 10.4236/eng.2010.24036
Abstract: In this paper, a new technique using a Current Shunt and a Micropotentiometer has been used to study the electrical performance of a large area multicrystalline silicon solar cell at outdoor conditions. The electrical performance is mainly described by measuring both cell short circuit current and open circuit voltage. The measurements of this cell by using multimeters suffer from some problems because the cell has high current intensity with low output voltage. So, the solar cell short circuit current values are obtained by measuring the voltage developed across a known resistance Current Shunt. Samples of the obtained current values are accurately calibrated by using a Micropotentiometer (μpot) thermal element (TE) to validate this new measuring technique. Moreover, the solar cell open circuit voltage has been measured. Besides, the cell output power has been calculated and can be correlated with the measured incident radiation.
Effects on Amorphous Silicon Photovoltaic Performance from High-temperature Annealing Pulses in Photovoltaic Thermal Hybrid Devices  [PDF]
M. J. M. Pathak,J. M. Pearce,S. J. Harrison
Physics , 2012, DOI: 10.1016/j.solmat.2012.01.015
Abstract: There is a renewed interest in photovoltaic solar thermal (PVT) hybrid systems, which harvest solar energy for heat and electricity. Typically, a main focus of a PVT system is to cool the photovoltaic (PV) cells to improve the electrical performance, however, this causes the thermal component to under-perform compared to a solar thermal collector. The low temperature coefficients of amorphous silicon (a-Si:H) allow for the PV cells to be operated at higher temperatures and are a potential candidate for a more symbiotic PVT system. The fundamental challenge of a-Si:H PV is light-induced degradation known as the Staebler-Wronski effect (SWE). Fortunately, SWE is reversible and the a-Si:H PV efficiency can be returned to its initial state if the cell is annealed. Thus an opportunity exists to deposit a-Si:H directly on the solar thermal absorber plate where the cells could reach the high temperatures required for annealing. In this study, this opportunity is explored experimentally. First a-Si:H PV cells were annealed for 1 hour at 100\degreeC on a 12 hour cycle and for the remaining time the cells were degraded at 50\degreeC in order to simulate stagnation of a PVT system for 1 hour once a day. It was found that, when comparing the cells after stabilization at normal 50\degreeC degradation, this annealing sequence resulted in a 10.6% energy gain when compared to a cell that was only degraded at 50\degreeC.
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