Photovoltaic Systems
Williams S. Ebhota; Pavel Tabakov
Abstract
This research provides concise insights into fossil fuel consumption challenges, and the factors contributing to global warming, and evaluates the significance of photovoltaic (PV) materials in achieving net-zero-CO2 emissions. The article categorizes constraints in the development of PV cells into four ...
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This research provides concise insights into fossil fuel consumption challenges, and the factors contributing to global warming, and evaluates the significance of photovoltaic (PV) materials in achieving net-zero-CO2 emissions. The article categorizes constraints in the development of PV cells into four main areas: technical factors, leadership impact, political instability, and financial aspects. Primarily, the study delves into technical factors, focusing on the power conversion efficiency (PCE) and power density of PV cells. Theoretically, approximately 67% of solar energy is dissipated in various forms - 47% as heat, 18% as photons, and 2% in local combination loss. Commercially available mono-crystalline silicon (c-Si) and poly-crystalline silicon (poly-c-Si) PV cells typically demonstrate a range of PCEs between 15% to 22% and 13% to 18%, respectively, presenting an efficiency considerably lower than the potential maximum of 100%. The study highlights organic photovoltaic cells (OPVs) as promising third-generation PV modules due to their relatively high power conversion efficiency (HPCE) and eco-friendly attributes. However, their commercial feasibility is under scrutiny owing to constraints such as a limited lifespan, high production costs, and challenges in mass production. Ongoing research and development (R&D) in PV cell technologies aim to enhance PCE and power density, establish cost-effective production methods, and create more reliable and sustainable supply chains. Additionally, the study explores the role of nanotechnology in developing high-power conversion efficiency cells, identifies research gaps and priorities in engineered organic material PV cells, and discusses the potential of OPVs in the R&D of high-efficiency, cost-effective, and environmentally friendly PV cells.
Photovoltaic Systems
Niti Agrawal
Abstract
Partial shading condition (PSC) has a detrimental effect on the output performance of a photovoltaic (PV) system. The output performance of a partially shaded PV array depends not only on the pattern, intensity and location of the shadow but also on its configuration. In this paper, the output performance ...
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Partial shading condition (PSC) has a detrimental effect on the output performance of a photovoltaic (PV) system. The output performance of a partially shaded PV array depends not only on the pattern, intensity and location of the shadow but also on its configuration. In this paper, the output performance of two configurations namely- series-parallel (SP), a commonly used configuration, and total-cross-tied (TCT), have been compared under diverse PSCs. A Lambert W-function-based technique has been developed to model, simulate and estimate the performance of both the configurations of the PV array. The developed program can evaluate the current, voltage and power for the arrays of different sizes under uniform and different PSCs. A detailed investigation has been carried out for the output performance of both configurations under nine diverse shading patterns and different sizes of arrays. Comparative analysis for the configurations is presented based on parameters such as maximum power obtained, partial shading power loss percentage, efficiency and fill factor. It has been found from the obtained results that the output performance of a PV array under PSC is enhanced by using TCT configuration compared to SP configuration.
Photovoltaic Systems
Christopher T Warburg; Tatiana Pogrebnaya; Thomas Kivevele
Abstract
This study delves into the ongoing discourse surrounding the optimal tilt angles for solar panels to maximize solar PV power generation. Focused on seven equatorial regions in Tanzania; Dodoma, Dar es Salaam, Kilimanjaro, Kigoma, Iringa, Mtwara, and Mwanza. Multiple mathematical models are employed to ...
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This study delves into the ongoing discourse surrounding the optimal tilt angles for solar panels to maximize solar PV power generation. Focused on seven equatorial regions in Tanzania; Dodoma, Dar es Salaam, Kilimanjaro, Kigoma, Iringa, Mtwara, and Mwanza. Multiple mathematical models are employed to ascertain the most efficient panel tilts. Leveraging solar radiation data spanning from 2000 to 2017, we developed an algorithm specifically tailored for computing suitable tilt angles in the southern hemisphere. Our investigation reveals compelling insights into the variation of optimal panel tilts throughout the year. Notably, the monthly optimal tilt angles fluctuate significantly across the regions. June emerges as the month with the highest recorded monthly optimal tilt angle, ranging from 45 degrees in Mtwara to 31 degrees in Kilimanjaro. Conversely, December showcases the lowest tilt angles, spanning from -30 degrees in Mwanza to -26 degrees in both Kigoma and Iringa. Quarterly angles exhibit peaks during the second quarter of the year, reaching 39 degrees in Mtwara and 27 degrees in Kilimanjaro, while experiencing declines in the fourth quarter, plunging to levels between -19 and -24 degrees. Additionally, our study calculates annual optimal tilt angles, revealing a range from 2 degrees in Kilimanjaro to 11 degrees in Mtwara. Crucially, the deployment of monthly optimally tilted solar PV panels demonstrates a noteworthy enhancement, yielding a 6-11% gain in solar radiation compared to horizontally mounted panels. Our study advocates for the adoption of dynamic tilt adjustment strategies of periodic angle alterations to maximize solar PV power generation.
Photovoltaic Systems
Pankaj Verma; Bharat Gangal; Gaurav Jain; Ravi Hada
Abstract
Most of the partial shading maximum power point tracking methods have been designed for the static shading pattern of the partial shading conditions, however, the irradiance pattern may change further when in partial shading mode. Therefore, to cover this research gap, a global maximum power point control ...
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Most of the partial shading maximum power point tracking methods have been designed for the static shading pattern of the partial shading conditions, however, the irradiance pattern may change further when in partial shading mode. Therefore, to cover this research gap, a global maximum power point control under varying irradiance (GCVI) algorithm is proposed in this paper. The algorithm does not use any sensors to detect the change in the irradiance, instead, the change in the current values of the modules are continuously monitored to detect the change. The reference voltages across which the peaks on the power curve are scanned are obtained from the reference voltage generation process, the consideration of these reference points avoids the excessive power losses in the system. The verification of the working of the proposed algorithm is carried out by simulating the photovoltaic system model on SIMULINK in MATLAB software. Simulations are carried out in various scenarios to show the effectiveness of the control. The simulation results illustrate that with the change in the global maximum under partial shading, the system successfully retunes to the new maximum point; the maximum point retunes from 10 kW to 9.2 kW and from 13.8 kW to 11.5 kW for two different case scenarios. Further, the comparisons are also carried out with the previously reported methods.
Photovoltaic Systems
Mustafa Arslan; Mehmet Cunkas
Abstract
Diffuse radiation is used in photovoltaic systems and other energy applications. Since global radiation is measured by local meteorological stations, it is possible to reach these radiation data. However, diffuse radiation is not usually measured, so it is not possible to obtain regular data on diffuse ...
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Diffuse radiation is used in photovoltaic systems and other energy applications. Since global radiation is measured by local meteorological stations, it is possible to reach these radiation data. However, diffuse radiation is not usually measured, so it is not possible to obtain regular data on diffuse radiation. For this reason, efforts are underway to develop various empirical models to estimate diffuse radiation. This paper aims to develop new empirical models to estimate the diffuse radiation values for Konya, Türkiye. The empirical models are used to determine the relationship between the diffuse fraction and the clearness index. Data from NASA-Surface meteorology and Solar Energy and the measured global solar were used. The three most suitable developed models were selected, and it was suggested to estimate the diffuse radiation. The developed models consist of 2nd, 3rd, and 4th-order polynomial regression models. The proposed models were tested to evaluate their performances by using eight statistical methods. These are Mean Bias Error (MBE), Mean Absolute Error (MAE), Mean Squared Error (MSE), Root Mean Squared Error (RMSE), Sum Squared Relative Error (SSRE), Relative Standard Error (RSE), Coefficient of determination (R2) and Correlation Coefficient (r). For the suggested models, the statistical parameters R2 value were calculated as 0.999705413, 1, and 1, and the RSE values were determined as 0.0084537, 0.000122, and 6.05E-06. The proposed models can contribute to researchers working on the applications of photovoltaic systems. The approaches could be used to estimate diffuse radiation elsewhere under similar climatic conditions.
Photovoltaic Systems
Mohammed Zaid Khan; Seema Agrawal
Abstract
This paper considers the context of renewable energy generation for a photo voltaic solar generating system with a non-linear load using one cycle controller with a motor across terminals. The paper finds a comparative study of the pulse width modulator with one cycle controller, which analyses both ...
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This paper considers the context of renewable energy generation for a photo voltaic solar generating system with a non-linear load using one cycle controller with a motor across terminals. The paper finds a comparative study of the pulse width modulator with one cycle controller, which analyses both concepts using power sim software. The main challenge is to reject power supply disturbance. The frequency switch controls the single constant cycle and regulates direct current supply but with transients. As in the case of pulse width modulation, transients appear. In comparison, the one-cycle controlling technique rejects power supply disturbance as the constant voltage maximum power point tracker returns a reference speed value with the speed sensor, so one switching cycle is combined with a dual compensator to reject power supply disturbance as photo voltaic solar generation resolves the supply disturbance in a closed-loop scheme using one cycle modulator. So, in the case of the pulse width modulation technique, the ideal efficiency using the pulse width modulation controller varies from 70.45 % to 75 %; in the case of the novel one-cycle control modulator's excellent efficiency varies from 95.17 % to 99.49 %. Since switching converters efficiently control the photo voltaic energy generation system using one cycle control modulator rather than a pulse width modulator, apart from the swift transient response, one-cycle control modulator imparts economically efficient reference tracking and robustness to the system. The outcome of the one-cycle controller and pulse width modulated controller validates the analysis of variance (ANOVA).
Photovoltaic Systems
Faridul Islam; Md. Mominul Islam
Abstract
Sustainable Development Goal 13 is an activity committed with the intention of stabilizing greenhouse gas (GHG) levels in the environment to stop potentially harmful human meddling with the climate system. GHG are released into the environment from various non-renewable energy sources of power generation ...
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Sustainable Development Goal 13 is an activity committed with the intention of stabilizing greenhouse gas (GHG) levels in the environment to stop potentially harmful human meddling with the climate system. GHG are released into the environment from various non-renewable energy sources of power generation and many industries that cause extensive damage to the environment. Some countries have begun to implement various pollution prevention strategies, such as power generation from renewable energy sources, which emit no greenhouse gases (GHG) or CO2. This study focuses on an analysis of GHG emission reduction along with the financial feasibility of a grid-connected 100MW PV solar system. This study uses RETScreen software to evaluate the GHG emissions reduction analysis as well as a financial analysis of the system. The annual electricity supplied to the local grid of the proposed PV power plant is 137,481MWh. The cost of reducing CO2 emissions has a positive impact on the overall cumulative cash flow of the proposed system.
Photovoltaic Systems
M. Mirzaei Omrani; M. Mirzaei Omrani
Abstract
Solar energy as renewable and clean energy has a remarkable share in improving the water-energy-food nexus. However, due to occupying a vast area of land, the development of large-scale photovoltaic systems is a serious challenge, particularly in regions with land restrictions. As a solution, it is argued ...
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Solar energy as renewable and clean energy has a remarkable share in improving the water-energy-food nexus. However, due to occupying a vast area of land, the development of large-scale photovoltaic systems is a serious challenge, particularly in regions with land restrictions. As a solution, it is argued that the installation of the floating photovoltaic systems on the water reservoirs can save land as well as reduce the evaporation rate. The aim of this study is to economically and environmentally evaluate the feasibility of the installation of a 10-megawatt floating photovoltaic power plant on a water reservoir. Results show that the payback period of investment and internal rate of return are achieved at 5.2 years and 20.4%, respectively. It is also found that if only 0.3% of the water reservoir surface is covered, evaporation volume will be decreased from 441.2 up to 515.2 thousand cubic meters. Moreover, environmental assessment demonstrates that 8470 to 15311 tons of CO2 and 27 to 52.3 tons of NOx are not released into the atmosphere. Ultimately, sensitivity analysis proves that if the capital cost is reduced by 30%, the payback period will be shortened to 3.6 years. Furthermore, such a project in Chah-nimeh will be profitable as long as the electricity purchasing tariffs are more than US$ 0.096/kWh.
Photovoltaic Systems
H. Eshghi; M. Kahani; M. Zamen
Abstract
The cooling process of photovoltaic (PV) panel is one the main issue in in the field of solar systems. The temperature of solar cells increases when solar radiation and also ambient temperature increase. Increasing the cell temperature reduces the electrical output power of the panels as well as their ...
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The cooling process of photovoltaic (PV) panel is one the main issue in in the field of solar systems. The temperature of solar cells increases when solar radiation and also ambient temperature increase. Increasing the cell temperature reduces the electrical output power of the panels as well as their lifetime. To solve this problem, various methods have been provided for cooling the panels. One of these methods is the application of heat pipes. In this research, a PV panel equipped with thermosyphon heat pipe is introduced. The thermosyphon was connected to the back sheet of the panel to enhance the cooling effect of the PV system. Instead of using polyvinyl fluoride polymer, unlike conventional panels, an aluminum plate was used to connect the heat pipe to the back of the panel to have better cooling. In addition, to increase the heat transfer area between heat pipe and back surface of the panel, a special groove was drilled on the aluminum plate. Three different filling ratios (25, 45 and 65%) of distilled water as the working fluid were used in thermosyphon. The best performance of the systems was obtained at 45% of filling ratio, in which, the electrical power of the PV panel equipped with heat pipe was around 3.2% better than the conventional PV panel. In this case, 6.8 °C temperature difference was observed in the water tank connected to the condenser section of heat pipe which means that 54 kJ heat was transferred to the water in the tank.
Photovoltaic Systems
A. Ahmadi; M. A. Ehyaei
Abstract
Entropy generation can be caused by the energy transfer from a high-temperature recourse to a low-temperature resource; this is defined by the second law of thermodynamics. This phenomenon can occur for the Earth by transferring the solar energy from the sun to the earth. The process of entropy generation ...
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Entropy generation can be caused by the energy transfer from a high-temperature recourse to a low-temperature resource; this is defined by the second law of thermodynamics. This phenomenon can occur for the Earth by transferring the solar energy from the sun to the earth. The process of entropy generation of the Earth is an important concept for the life of the earth. This process also has significant effects on the global hydrological cycle, carbon cycle of the Earth’s atmosphere, and global warming. This paper presents an approximate method to estimate the entropy generation of the earth caused by the sun. Application of the heat engine to calculate the entropy generation of the planets has been carried out so far. In this research work, the concept of heat engine is applied to calculate the entropy generation of the earth and the atmosphere surrounding it in a relatively simple model. Based upon this calculation, the rate of entropy generation of the earth and its surrounding atmosphere is . Moreover, by considering this imaginative heat engine, the first and second law efficiencies are equal to 0.11036 % and 0.11546 %, respectively. The results of this research work have also been justified by similar works on this topic.
Photovoltaic Systems
N.O. Adeniji; J.O. Adeniji; O. Ojeikere
Abstract
Global solar radiation is the sum total of all radiation reaching the earth surface i.e. it includes: the direct and the diffused solar radiation reaching the earth surface. The instrument used for measuring this very important component arriving from the whole hemisphere is the pyranometer. This is ...
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Global solar radiation is the sum total of all radiation reaching the earth surface i.e. it includes: the direct and the diffused solar radiation reaching the earth surface. The instrument used for measuring this very important component arriving from the whole hemisphere is the pyranometer. This is one of the most important parameter for applications, developments and researches related to alternative source of clean and renewable energy. In cases where these data are not available, it is very common to use computational models to estimate the missing data, which are based mainly on the search for relationships between weather variables, such as temperature, humidity, precipitation, cloud cover and sunshine hours, among others. In this research work, the baseline data for mean monthly global solar radiation and sunshine hours for three (3) geopolitical zones of Nigeria (sub-sahara regions of Nigeria) with Sokoto (North-western Nigeria) (12.910N, 5.200E), Maiduguri (North-eastern Nigeria) (11.850N, 13.080E) and Ilorin (North- Central Nigeria) (8.430N, 4.500E) were obtained from the Nigeria Metrological Agency (NIMET), Nigeria which spread from 1996 to 2010. A linear regression correlation model was developed and clearness index estimated for each station in this study. The result shows the Angstrom coefficients and for estimating global solar radiation for zone respectively, using the Angstrom-Prescott model. The average global solar radiation for these stations was estimated, results subjected to statistical tests proven to be good estimates. The study concluded that the Angstrom- Prescott model plays a significant role in predicting and estimating solar energy potentials in these regions
Photovoltaic Systems
M. Lak Kamari; H. Isvand; M. Alhuyi Nazari
Abstract
Renewable energies are noticeably developing due to their various advantages such as low greenhouse gases emission, availability and their reducing cost trend. In order to achieve the favorable objectives in energy projects, it is crucial to consider all the related parameters affecting the decision ...
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Renewable energies are noticeably developing due to their various advantages such as low greenhouse gases emission, availability and their reducing cost trend. In order to achieve the favorable objectives in energy projects, it is crucial to consider all the related parameters affecting the decision making. Multi Criteria Decision Making (MCDM) methods are reliable and efficient tool for policy making and achieving the most appropriate solution. These approaches consider the influential factors and their relative importance in prioritizing the alternatives. Since the outcome of the MCDM approaches depend on the employed algorithm and the used criteria, this article focuses on the studies related to the applications of these methods in renewable energy technology selection. The aim of the present paper is extracting the criteria which are necessary to be used in decision making for renewable energy systems. In addition, the approaches employed for improving the performance of MCDM methods as decision making aids are represented. According to this review study, technical, economic and environmental criteria are utilized in the majority of decision making researches. Moreover, some of the studies have considered other criteria such as social and risk to achieve more reliable decision. Some ideas are represented in the reviewed researches such as integrating different methods and using fuzzy sets, instead of crisp sets, to improve the performance of the MCDM methods and reduce the uncertainties.