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Keywords = non-uniform solar irradiation

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31 pages, 57273 KiB  
Article
A New Hybrid Framework for the MPPT of Solar PV Systems Under Partial Shaded Scenarios
by Rahul Bisht, Afzal Sikander, Anurag Sharma, Khalid Abidi, Muhammad Ramadan Saifuddin and Sze Sing Lee
Sustainability 2025, 17(12), 5285; https://doi.org/10.3390/su17125285 - 7 Jun 2025
Viewed by 486
Abstract
Nonlinear characteristics of solar photovoltaic (PV) and nonuniform surrounding conditions, including partial shading conditions (PSCs), are the major factors responsible for lower conversion efficiency in solar panels. One major condition is the cause of the multiple peaks and oscillation around the peak point [...] Read more.
Nonlinear characteristics of solar photovoltaic (PV) and nonuniform surrounding conditions, including partial shading conditions (PSCs), are the major factors responsible for lower conversion efficiency in solar panels. One major condition is the cause of the multiple peaks and oscillation around the peak point leading to power losses. Therefore, this study proposes a novel hybrid framework based on an artificial neural network (ANN) and fractional order PID (FOPID) controller, where new algorithms are employed to train the ANN model and to tune the FOPID controller. The primary aim is to maintain the computed power close to its true peak power while mitigating persistent oscillations in the face of continuously varying surrounding conditions. Firstly, a modified shuffled frog leap algorithm (MSFLA) was employed to train the feed-forward ANN model using real-world solar PV data with the aim of generating a reference solar PV peak voltage. Subsequently, the parameters of the FOPID controller were tuned through the application of the Sanitized Teacher–Learning-Based Optimization (s-TLBO) algorithm, with a specific focus on achieving maximum power point tracking (MPPT). The robustness of the proposed hybrid framework was assessed using two different types (monocrystalline and polycrystalline) of solar panels exposed to varying levels of irradiance. Additionally, the framework’s performance was rigorously tested under cloudy conditions and in the presence of various partial shading scenarios. Furthermore, the adaptability of the proposed framework to different solar panel array configurations was evaluated. This work’s findings reveal that the proposed hybrid framework consistently achieves maximum power point with minimal oscillation, surpassing the performance of recently published works across various critical performance metrics, including the MPPefficiency, relative error (RE), mean squared error (MSE), and tracking speed. Full article
(This article belongs to the Section Energy Sustainability)
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24 pages, 5240 KiB  
Article
Vector-Based Advanced Computation for Photovoltaic Devices and Arrays: Numerical Reproduction of Unusual Behaviors of Curved Photovoltaic Devices
by Kenji Araki, Yasuyuki Ota and Kensuke Nishioka
Appl. Sci. 2024, 14(11), 4855; https://doi.org/10.3390/app14114855 - 4 Jun 2024
Cited by 3 | Viewed by 2434
Abstract
Most equations and models for photovoltaics are based on the assumption that photovoltaic (PV) devices are flat. Therefore, the actual performance of nonplanar PV devices should be investigated and developed. In this study, two algorithms were developed and defined using vector computations to [...] Read more.
Most equations and models for photovoltaics are based on the assumption that photovoltaic (PV) devices are flat. Therefore, the actual performance of nonplanar PV devices should be investigated and developed. In this study, two algorithms were developed and defined using vector computations to describe a curved surface based on differential geometry and the interaction with non-uniform solar irradiance (i.e., non-uniform shading distribution in the sky). To validate the computational model, the power output from a commercial curved solar panel for the Toyota Prius 40 series was monitored at four orientation angles and in various climates. Then, these were compared with the calculation results obtained using the developed algorithm. The conventional calculation used for flat PV devices showed an overestimated performance due to ignorance of inherent errors due to curved surfaces. However, the new algorithms matched the measured trends, particularly on clear-sky days. The validated computation method for curved PV devices is advantageous for vehicle-integrated photovoltaic devices and PVs including building-integrated photovoltaics (BIPVs), drones, and agriphotovoltaics. Full article
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22 pages, 7143 KiB  
Article
Numerical Modeling and Experimental Validation of Heat Transfer Characteristics in Small PTCs with Nonevacuated Receivers
by Amedeo Ebolese, Domenico Marano, Carlo Copeta, Agatino Bruno and Vincenzo Sabatelli
Solar 2023, 3(4), 544-565; https://doi.org/10.3390/solar3040030 - 12 Oct 2023
Viewed by 2374
Abstract
The development of small-sized parabolic trough collectors (PTCs) for processing heat production at medium temperatures (100–250 °C) represents an interesting approach to increase the utilization of solar thermal technologies in industrial applications. Thus, the development of simplified models to analyze and predict their [...] Read more.
The development of small-sized parabolic trough collectors (PTCs) for processing heat production at medium temperatures (100–250 °C) represents an interesting approach to increase the utilization of solar thermal technologies in industrial applications. Thus, the development of simplified models to analyze and predict their performance under different operative and climatic conditions is crucial for evaluating the application potential of this low-cost technology. In this paper, we present a numerical method that by combining three-dimensional finite element simulations (implemented with COMSOL Multiphysics software version 6.1) with a one-dimensional analysis (based on a MATLAB script) allows for the theoretical determination of the power output of a small-PTC with a nonevacuated tubular receiver operating at a medium temperature. The finite element model considers both the nonuniformity of the concentrated solar flux on the receiver tube (evaluated using Monte Carlo ray-tracing analysis) and the establishment of natural convection in the air gap between the glass envelope and absorber tube. The model calculates, for several values of direct normal irradiance (DNI) and inlet temperatures, the thermal power transferred to the heat transfer fluid (HTF) per unit length. The data are fitted using the multiple linear regression method, obtaining a function that is then used in a one-dimensional multi-nodal model to estimate the temperatures and the heat gains along the receiver tube. The outputs of the model are the outlet temperature and the total thermal power transferred to the HTF. In order to validate the developed methodology for the assessment of the heat transfer characteristics in the small-PTC with a nonevacuated receiver, an experiment at the ENEA Trisaia—Solar Thermal Collector Testing Laboratory was carried out. This work compares the theoretical data with those acquired through experimentation, obtaining a good agreement, with maximum differences of 0.2% and 3.6% for the outlet temperatures and the power outputs, respectively. Full article
(This article belongs to the Special Issue Recent Advances in Solar Thermal Energy)
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20 pages, 6471 KiB  
Article
Impact of Non-Uniform Irradiance and Temperature Distribution on the Performance of Photovoltaic Generators
by Petrakis Thomas, Aphrodite Ktena, Panagiotis Kosmopoulos, John Konstantaras and Michael Vrachopoulos
Energies 2023, 16(17), 6322; https://doi.org/10.3390/en16176322 - 31 Aug 2023
Cited by 2 | Viewed by 2358
Abstract
The use of photovoltaic (PV) panels has increased rapidly in the last few years and as a result has become one of the main sources of renewable energy. In this context, it is important to understand in detail how a PV panel reacts [...] Read more.
The use of photovoltaic (PV) panels has increased rapidly in the last few years and as a result has become one of the main sources of renewable energy. In this context, it is important to understand in detail how a PV panel reacts to different environmental conditions and how these affect total performance. An experiment has been designed to investigate the performance of a PV panel under various highly non-uniform temperature and irradiance profiles, generated by artificial lighting. Measurements of irradiance and temperature distribution are related to measured I–V curves and used as input to the five-parameter model. The results show the limitations of the model to emulate the PV response under such extreme conditions and provide useful insights about the effect of the temperature profile on the PV performance. Full article
(This article belongs to the Special Issue Advances on Solar Energy Materials and Solar Cells)
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15 pages, 4556 KiB  
Article
Seamless Start-Up of a Grid-Connected Photovoltaic System Using Module-Integrated Micro-Converters
by Leonardo Callegaro, Trung-Hieu Uong and Sara Deilami
Energies 2023, 16(17), 6181; https://doi.org/10.3390/en16176181 - 25 Aug 2023
Cited by 3 | Viewed by 1460
Abstract
In traditional grid-tied photovoltaic (PV) installations, when partial shadowing occurs between different PV modules in a string, bypass diodes short-circuit the output terminals of shadowed modules, and the whole system forgoes their potential energy production. This loss can be recovered if a dc-dc [...] Read more.
In traditional grid-tied photovoltaic (PV) installations, when partial shadowing occurs between different PV modules in a string, bypass diodes short-circuit the output terminals of shadowed modules, and the whole system forgoes their potential energy production. This loss can be recovered if a dc-dc converter (micro-converter) is coupled to every PV module, and operated at the maximum power point (MPP). In this scenario, without communication links between the distributed micro-converter and the grid-tied inverter, a start-up procedure must be carefully designed to seamlessly allow the system to transfer PV power to the grid. During this phase, potentially damaging over-voltages and abrupt transients occurring at the micro-converters/inverter interface must be avoided. In this paper, the control algorithm of each micro-converter is enhanced to provide a smooth start-up operation so that PV units can safely start transferring power to the inverter and the grid. Improving from previous works, the proposed control technique is simple and removes the need for current sensors at the output of each micro-converter and at the inverter dc-link, with an economical advantage. Simulation results demonstrate the successful system start-up behavior, whilst confirming the benefits of the proposed control technique. First, the dc-link is energized from the rectified grid voltage. Then, the micro-converters raise the dc-link voltage so that the available PV power is transferred to the grid, with this sequence of operations not causing any abrupt electrical transient. The results also demonstrate the robust behavior of the PV system under non-uniform solar irradiation conditions. Full article
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20 pages, 11920 KiB  
Article
3D Solar Irradiance Model for Non-Uniform Shading Environments Using Shading (Aperture) Matrix Enhanced by Local Coordinate System
by Kenji Araki, Yasuyuki Ota, Akira Nagaoka and Kensuke Nishioka
Energies 2023, 16(11), 4414; https://doi.org/10.3390/en16114414 - 30 May 2023
Cited by 18 | Viewed by 3956
Abstract
Building-integrated photovoltaics (BIPVs) and vehicle-integrated photovoltaics (VIPVs) receive solar irradiance through non-uniform shading objects. Standard scalar calculations cannot accurately determine the solar irradiance of BIPV and VIPV systems. This study proposes a matrix model using an aperture matrix to accurately calculate the horizontal [...] Read more.
Building-integrated photovoltaics (BIPVs) and vehicle-integrated photovoltaics (VIPVs) receive solar irradiance through non-uniform shading objects. Standard scalar calculations cannot accurately determine the solar irradiance of BIPV and VIPV systems. This study proposes a matrix model using an aperture matrix to accurately calculate the horizontal and vertical planes affected by non-uniform shading objects. This can be extended to the solar irradiance on a VIPV by applying a local coordinate system. The 3D model is validated by a simultaneous measurement of five orientations (roof and four sides, front, left, tail, and right) of solar irradiance on a car body. An accumulated logistic function can approximate the shading probability. Furthermore, the combined use of the 3D solar irradiance model is effective in assessing the energy performance of solar electric vehicles in various zones, including buildings, residential areas, and open spaces. Unlike standard solar energy systems, the energy yield of a VIPV is affected by the shading environment. This, in turn, is affected mainly by the location of vehicle travel or parking in the city rather than by the climate zones of the city. Full article
(This article belongs to the Special Issue Forecasting, Modeling, and Optimization of Photovoltaic Systems)
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25 pages, 14664 KiB  
Article
Solar Electric Vehicles as Energy Sources in Disaster Zones: Physical and Social Factors
by Kenji Araki, Yasuyuki Ota, Anju Maeda, Minoru Kumano and Kensuke Nishioka
Energies 2023, 16(8), 3580; https://doi.org/10.3390/en16083580 - 20 Apr 2023
Cited by 13 | Viewed by 5029
Abstract
Electric vehicles (EVs) have the advantage of being resilient to natural disasters. However, users hesitate to donate electricity when they lose the chance to recharge at the utility. Solar electric vehicles (SEVs) save energy through vehicle-integrated photovoltaics (VIPV) and make it possible to [...] Read more.
Electric vehicles (EVs) have the advantage of being resilient to natural disasters. However, users hesitate to donate electricity when they lose the chance to recharge at the utility. Solar electric vehicles (SEVs) save energy through vehicle-integrated photovoltaics (VIPV) and make it possible to voluntarily donate excess energy, thus maintaining facility resilience. Given that the supply of solar energy to VIPV systems is not continuous and is difficult to forecast, the contribution of VIPV to the resilience of the larger energy system has been called into question. This is the first study in which the potential of VIPV to maintain utility resilience is investigated in the context of physical factors, such as irradiance, and social factors. The actual energy yield of a VIPV car was determined using an advanced 3D solar irradiation model under a nonuniform shading distribution, with validation from actual measures of solar irradiance on five orthogonal sides of the car body. The Monte Carlo method was used to model the complex factors in VIPV energy storage and energy donations under different scenarios. Depending on the climate, population density, and shading environment, the voluntary contribution of stored electricity in SEV is sufficient to provide disaster relief support. Full article
(This article belongs to the Collection Renewable Energy and Energy Storage Systems)
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30 pages, 17183 KiB  
Article
Modeling, Simulation, and Experimental Validation of a Novel MPPT for Hybrid Renewable Sources Integrated with UPQC: An Application of Jellyfish Search Optimizer
by Ahmed Hussain Elmetwaly, Ramy Adel Younis, Abdelazeem Abdallah Abdelsalam, Ahmed Ibrahim Omar, Mohamed Metwally Mahmoud, Faisal Alsaif, Adel El-Shahat and Mohamed Attya Saad
Sustainability 2023, 15(6), 5209; https://doi.org/10.3390/su15065209 - 15 Mar 2023
Cited by 35 | Viewed by 2514
Abstract
Changes in climatic circumstances, as well as intermittency, which has a significant impact on the overall energy system output from renewable energy sources (RESs), require the development of control strategies for extracting the maximum power available from RESs. To accomplish this task, several [...] Read more.
Changes in climatic circumstances, as well as intermittency, which has a significant impact on the overall energy system output from renewable energy sources (RESs), require the development of control strategies for extracting the maximum power available from RESs. To accomplish this task, several techniques have been developed. An efficient maximum power point tracking (MPPT) technique should be utilized to guarantee that both wind-generation and PV-generation systems provide their full advantages. In this paper, a new MPPT approach with jellyfish search optimization (JSO) is developed; in addition, a unified power-quality conditioner (UPQC) is utilized to enhance the performance of the microgrid (MG) and to solve the power-quality issues for the sensitive load. The MG, which includes a photovoltaic (PV), a wind turbine, and a fuel cell battery, is examined and modeled for uniform and nonuniform wind speed and solar irradiance. A comparison between the developed algorithm and different maximum power tracking algorithms is presented. Additionally, four case studies are carried out to verify the effectiveness of the introduced UPQC in enhancing power-quality problems. The research outcome shows high performance from the developed algorithm when assessed with additional algorithms. MATLAB/Simulink software is utilized for the simulation of the wind, PV, and FC control systems. However, experiment validation tests are given under the same condition of PV irradiation to validate the simulation results. The experimental validation is executed by utilizing the PV module simulation model, threefold, 23 V/2A CO3208-1A with solar altitude emulator CO3208-1B board, and the results are compared to the simulation results. Full article
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16 pages, 4516 KiB  
Article
Optimizing the Spatial Nonuniformity of Irradiance in a Large-Area LED Solar Simulator
by Alaa Al-Ahmad, John Holdsworth, Benjamin Vaughan, Warwick Belcher, Xiaojing Zhou and Paul Dastoor
Energies 2022, 15(22), 8393; https://doi.org/10.3390/en15228393 - 10 Nov 2022
Cited by 4 | Viewed by 3009
Abstract
The solar simulator has allowed all photovoltaic devices to be developed and tested under laboratory conditions. Filtered xenon arc lamps were the gold-standard source for solar simulation of small-area silicon photovoltaic devices; however, scaling these devices to illuminate large areas is neither efficient [...] Read more.
The solar simulator has allowed all photovoltaic devices to be developed and tested under laboratory conditions. Filtered xenon arc lamps were the gold-standard source for solar simulation of small-area silicon photovoltaic devices; however, scaling these devices to illuminate large areas is neither efficient nor practical. Large-area solar simulation to meet appropriate spectral content and spatial nonuniformity of irradiance (SNI) standards has traditionally been difficult and expensive to achieve, partly due to the light sources employed. LED-based solar simulation allows a better electrical efficiency and uniformity of irradiance while meeting spectral intensity requirements with better form factors. This work details the design based on optical modeling of a scalable, large-area, LED-based, solar simulator meeting Class AAA performance standards formed for inline testing of printed solar cells. The modular design approach employed enables the illuminated area to be expanded in quanta of ~260 cm2 to any preferred illumination area. A 640 cm2 area illuminated by two adjacent PCB units has a measured total emission of 100 mW/cm2, with a SNI of 1.7% and an excellent approximation to the AM1.5G spectrum over the wavelength range of 350–1100 nm. The measured long-term temporal instability of irradiance (TIE) is <0.5% for a 550-min continuous run. This work identifies the design steps and details the development and measurement of a scalable large-area LED-based solar simulator of interest to the PV testing community, and others using solar simulators. Full article
(This article belongs to the Special Issue Solar Energy: Resources, Technologies and Challenges)
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29 pages, 4471 KiB  
Review
Enhanced Maximum Power Point Techniques for Solar Photovoltaic System under Uniform Insolation and Partial Shading Conditions: A Review
by Laxman Bhukya, Narender Reddy Kedika and Surender Reddy Salkuti
Algorithms 2022, 15(10), 365; https://doi.org/10.3390/a15100365 - 29 Sep 2022
Cited by 95 | Viewed by 5080
Abstract
In the recent past, the solar photovoltaic (PV) system has emerged as the most promising source of alternative energy. This solar PV system suffers from an unavoidable phenomenon due to the fluctuating environmental conditions. It has nonlinearity in I-V curves, which reduces the [...] Read more.
In the recent past, the solar photovoltaic (PV) system has emerged as the most promising source of alternative energy. This solar PV system suffers from an unavoidable phenomenon due to the fluctuating environmental conditions. It has nonlinearity in I-V curves, which reduces the output efficiency. Hence, the optimum maximum power point (MPP) extraction of the PV system is difficult to achieve. Therefore, for maximizing the power output of PV systems, a maximum power point tracking (MPPT) mechanism, which is a control algorithm that can constantly track the MPP during operation, is required. However, choosing a suitable MPPT technique might be confusing because each method has its own set of advantages and disadvantages. Hence, a proper review of these methods is essential. In this paper, a state-of-the-art review on various MPPT techniques based on their classifications, such as offline, online, and hybrid techniques under uniform and nonuniform irradiances, is presented. In comparison to offline and online MPPT methods, intelligent MPPT techniques have better tracking accuracy and tracking efficiency with less steady state oscillations. Unlike online and offline techniques, intelligent methods track the global MPP under partial shade conditions. This review paper will be a useful resource for researchers, as well as practicing engineers, to pave the way for additional research and development in the MPPT field. Full article
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15 pages, 4418 KiB  
Article
Analysis and Experiment of Laser Wireless Power Transmission Based on Photovoltaic Panel
by Tiefeng He, Guoliang Zheng, Xing Liu, Qingyang Wu, Meng Wang, Can Yang and Zhijian Lv
Photonics 2022, 9(10), 684; https://doi.org/10.3390/photonics9100684 - 22 Sep 2022
Cited by 8 | Viewed by 3964
Abstract
A photovoltaic panels is a device used for converting solar and other energy into electrical energy. In laser wireless power transmission, there is a problem that the conversion efficiency of the photovoltaic panel is not as high as that of a single photovoltaic [...] Read more.
A photovoltaic panels is a device used for converting solar and other energy into electrical energy. In laser wireless power transmission, there is a problem that the conversion efficiency of the photovoltaic panel is not as high as that of a single photovoltaic cell, and the output power is not as large as expected. This is not conducive to the popularization and use of wireless power transmission via laser. It is important to find out why the output power of the photovoltaic panel irradiated by lasers is not high. According to the laser intensity distribution equation, it is deduced that the laser in a very small area has an equivalent uniformity intensity distribution through the comparative calculation of the light intensity of two adjacent points. Then, the input non-uniform laser can be broken down into many equivalent uniform small lasers with different light intensity values. Based on this theory, the photovoltaic array model under laser was established, and it was simulated by MATLAB/Simulink. The simulation results reveal that the greater the difference between the light intensity values of these small spots, that is to say, the more non-uniform the laser, the lower the output power of the photovoltaic module illuminated by it. A multi-wavelength experimental platform was built, and comparative experiments of laser wireless power transmission were carried out using three kinds of lasers: 808, 532, and 1030 nm. The experimental result was in good agreement with the simulation result. The above results show that the deduced theory and the model based on it are correct. Full article
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16 pages, 3539 KiB  
Article
Effect of Gamma Irradiation on the Structural, Optical, Electrical, and Ferroelectric Characterizations of Bismuth-Modified Barium Titanate Ceramics
by Hanan Al-Ghamdi, Aljawhara H. Almuqrin and Hamoud Kassim
Materials 2022, 15(12), 4337; https://doi.org/10.3390/ma15124337 - 19 Jun 2022
Cited by 9 | Viewed by 3152
Abstract
Materials with ferroelectric properties, low bandgap energies, high polarization, low loss, and thermal stability are essential for future solar-cell applications. Researchers have attempted to obtain such materials by using several approaches. In this vein, a novel approach is reported in this work using [...] Read more.
Materials with ferroelectric properties, low bandgap energies, high polarization, low loss, and thermal stability are essential for future solar-cell applications. Researchers have attempted to obtain such materials by using several approaches. In this vein, a novel approach is reported in this work using gamma ray irradiation. The effect of gamma radiation on the structural, optical, and ferroelectric characterizations of bismuth (Bi)-doped barium titanate (BaTiO3 (BT)), namely Ba0.95Bi0.05TiO3 ceramics (abbreviated as (Bi:BT)), was investigated. X-ray diffraction, structure refinement, and Raman study revealed the presence of a perovskite structure with a tetragonal phase in all investigated samples. Morphological study revealed a nonuniform grain size and some porosity. Gamma irradiation-induced combined effects were proved by a detailed analysis of bond lengths, bond angles, octahedral distortions, oxygen vacancies, and charge compensations. Electron paramagnetic resonance (EPR) study gave direct evidence of oxygen vacancies in the irradiated samples. After gamma irradiation, UV–vis study indicated a decrease in the bandgap from 3.14 to 2.80 eV and a significant increase in visible light absorption. Cole–Cole plots confirm as an increase in gamma-ray dose results in higher levels of electron hopping. Study of the P–E hysteresis loop demonstrated that ferroelectric properties could be maintained after gamma irradiation, with a slight decrease in remnant polarization. The behaviour of the P–E was correlated with increasing gamma dose in the investigated ceramics, demonstrating a strong gamma dependence in the loops’ profile. We guess that the present approach may be a promising technique for enhancing the multifunctionality of electronic devices. Full article
(This article belongs to the Section Advanced and Functional Ceramics and Glasses)
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13 pages, 2072 KiB  
Article
Carbon Black/Polyvinylidene Fluoride Nanocomposite Membranes for Direct Solar Distillation
by Marcello Pagliero, Marina Alloisio, Camilla Costa, Raffaella Firpo, Ermias Ararsa Mideksa and Antonio Comite
Energies 2022, 15(3), 740; https://doi.org/10.3390/en15030740 - 20 Jan 2022
Cited by 13 | Viewed by 3352
Abstract
Water reclamation is becoming a growing need, in particular in developing countries where harvesting the required energy can be a challenging problem. In this context, exploiting solar energy in a specifically tailored membrane distillation (MD) process can be a viable solution. Traditional MD [...] Read more.
Water reclamation is becoming a growing need, in particular in developing countries where harvesting the required energy can be a challenging problem. In this context, exploiting solar energy in a specifically tailored membrane distillation (MD) process can be a viable solution. Traditional MD guarantees a complete retention of non-volatile compounds and does not require high feed water temperatures. In this work, a suitable amount of carbon black (CB) was incorporated into the whole matrix of a polymeric porous membrane in order to absorb light and directly heat the feed. The mixed matrix membranes were prepared forming a uniform CB dispersion in the PVDF dope solution and then using a non-solvent induced phase separation process, which is a well-established technique for membrane manufacturing. CB addition was found to be beneficial on both the membrane structure, as it increased the pore size and porosity, and on the photothermal properties of the matrix. In fact, temperatures as high as 60 °C were reached on the irradiated membrane surface. These improvements led to satisfactory distillate flux (up to 2.3 L/m2h) during the direct solar membrane distillation tests performed with artificial light sources and make this membrane type a promising candidate for practical applications in the field of water purification. Full article
(This article belongs to the Special Issue Thermal Performance of Membrane Distillation)
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15 pages, 6605 KiB  
Article
Study of the Radiation Flux Distribution in a Parabolic Dish Concentrator
by Nidia Aracely Cisneros-Cárdenas, Rafael Cabanillas-López, Ricardo Pérez-Enciso, Guillermo Martínez-Rodríguez, Rafael García-Gutiérrez, Carlos Pérez-Rábago, Ramiro Calleja-Valdez and David Riveros-Rosas
Energies 2021, 14(21), 7053; https://doi.org/10.3390/en14217053 - 28 Oct 2021
Cited by 6 | Viewed by 2748
Abstract
The radiation flux distributions produced by the concentrating solar systems used to produce thermal/electrical power are usually non-homogeneous. This results in non-uniform temperature distributions on the solar receivers, causing adverse effects on the system’s overall performance. An approach to better understand the problem [...] Read more.
The radiation flux distributions produced by the concentrating solar systems used to produce thermal/electrical power are usually non-homogeneous. This results in non-uniform temperature distributions on the solar receivers, causing adverse effects on the system’s overall performance. An approach to better understand the problem is to study the surfaces around the focal zone where the radiation density is homogeneous (isosurfaces), generating them from experimental data. For this, it is necessary to superimpose built volumes of the different irradiance levels using parallel planes in different directions from the focal point of a concentrator. These volumes are known as effective volumes. This study presents the model used to generate effective volume produced by a point focus concentrator, comparing it with experimental results in a direction perpendicular to the focal axis. The effective volumes were developed considering a global optical error of the system of 2.8 mrad. The set of methods used to generate effective volumes has not been previously presented in the literature. The theoretical-experimental research consisted of the combination of the camera-target method and the simulations by the ray-tracing technique. The results showed effective volumes with the highest value of 10 MW/m2 and the lowest value of 4.5 MW/m2. Full article
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23 pages, 46601 KiB  
Article
A Fast-Tracking Hybrid MPPT Based on Surface-Based Polynomial Fitting and P&O Methods for Solar PV under Partial Shaded Conditions
by Catalina González-Castaño, Carlos Restrepo, Javier Revelo-Fuelagán, Leandro L. Lorente-Leyva and Diego H. Peluffo-Ordóñez
Mathematics 2021, 9(21), 2732; https://doi.org/10.3390/math9212732 - 28 Oct 2021
Cited by 9 | Viewed by 2853
Abstract
The efficiency of photovoltaic (PV) systems depends directly on solar irradiation, so drastic variations in solar exposure will undoubtedly move its maximum power point (MPP). Furthermore, the presence of partial shading conditions (PSCs) generates local maximum power points (LMPPs) and one global maximum [...] Read more.
The efficiency of photovoltaic (PV) systems depends directly on solar irradiation, so drastic variations in solar exposure will undoubtedly move its maximum power point (MPP). Furthermore, the presence of partial shading conditions (PSCs) generates local maximum power points (LMPPs) and one global maximum power point (GMPP) in the P-V characteristic curve. Therefore, a proper maximum power point tracking (MPPT) technique is crucial to increase PV system efficiency. There are classical, intelligent, optimal, and hybrid MPPT techniques; this paper presents a novel hybrid MPPT technique that combines Surface-Based Polynomial Fitting (SPF) and Perturbation and Observation (P&O) for solar PV generation under PSCs. The development of the experimental PV system has two stages: (i) Modeling the PV array with the DC-DC boost converter using a real-time and high-speed simulator (PLECS RT Box), (ii) and implementing the proposed GMPPT algorithm with the double-loop controller of the DC-DC boost converter in a commercial low-priced digital signal controller (DSC). According to the simulation and the experimental results, the suggested hybrid algorithm is effective at tracking the GMPP under both uniform and nonuniform irradiance conditions in six scenarios: (i) system start-up, (ii) uniform irradiance variations, (iii) sharp change of the (PSCs), (iv) multiple peaks in the P-V characteristic, (v) dark cloud passing, and (vi) light cloud passing. Finally, the experimental results—through the standard errors and the mean power tracked and tracking factor scores—proved that the proposed hybrid SPF-P&O MPPT technique reaches the convergence to GMPP faster than benchmark approaches when dealing with PSCs. Full article
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