Advances in Green Energies and Materials Technology

Etching of Indium Tin Oxide (ITO) is an important step in the realization of organic photovoltaic cells. In the case of a glass substrate, the etching is carried out by hiding the areas that are to be preserved by varnish, then the samples are put in hydrochloric acid HCl, after that the samples will be cleaned in alcohols baths: acetone, ethanol and isopropanol. In the case of flexible substrates, the use of acetone to remove the varnish damages the plastic substrate. The solution to remedy this degradation is to use new technic which is photolithography. Flexible solar cells are made. The transparent electrode consists of ITO deposited on polyethylene terephthalate (PET). The active layer is composed on poly (3-hexylthiophene-2,5-diyl) (P3HT) and methyl ester of butyric acid [6,6]-phenyl C61 (PCBM). Poly (3,4-ethylenedioxythiophene)-polystyrene sulfonate of aluminum. The structure of the final device is: PET/ITO/PEDOT:PSS/P3HT:PCBM/Al. the results obtained show that photolithography etching is an efficient technic for determining the geometry of the electrodes without causing damage to the plastic substrates.

The aim of this work is the study of the effect of solution concentration in the optical and electrical properties of copper oxide thin films deposited by ultrasonic spray pyrolysis technique in order to obtain good photoelectric properties which makes it an important candidate in many technological applications. These films are elaborated onto glass substrates from an aqueous solution of copper (II) chloride dihydrate with different solution concentrations. Substrate temperature, nozzle-substrate distance, and deposition time were kept constant during the whole deposition process. After the deposition, we annealed these films in air at 400 °C for 120 min. UV-Visible spectrophotometry and the four-point method were used to evaluate the optical and electrical properties, the films obtained are p-type semiconductors, high optical absorption in the UV-Visible domains, rough surface with good adhesion to the substrate. Optical and electrical properties of undoped copper oxide thin films varied by the variation of solution concentration.

The experimental FT-IR spectrum of hydrindantin dihydrate (C18H10O6. 2H2O) has been investigated for the first time. The vibrational spectral signatures of OH stretching modes have been analyzed by using the results of density functional theory (DFT) calculations performed in the solid state. These results have shown that the IR bands due to the asymmetric (υasOH) and symmetric (υsOH) stretching modes of water molecules are overlapped in the large band centered at 3433 cm−1 in the experimental spectrum. While, the stretching bands due to the OH groups of hydrindantin molecules are red shifted to 2831 cm−1 owing to the formation of strong inter-molecular O–H···O hydrogen bonds with adjacent water molecules. Moreover, this study has been extended to reveal some calculated electronic properties of the isolated hydrindantin molecule.

The absorber of a Fresnel solar concentrator heats up and loses heat to the outside in a form of radiation and convection. This loss can be characterized by a coefficient of heat losses U generally brought to the surface of the mirrors. A heat transfer fluid cools the absorber carrying the useful heat which is then converted or transferred for different uses. The purpose of this work is to provide an analysis of the thermal behavior of a Fresnel concentrator solar receiver. Simulation of thermal transfers using the Fluent software was carried out to determine the different thermal losses in the receiver, namely the convective and radiative losses which appear in various elements of the receiver (the tube, the glass and the casing). To this end, the temperature distribution in the absorber, the linear thermal losses, and the overall thermal losses were determined, analyzed and discussed.

In this paper, we study a comparative problem, analysis, with and without MPPT regulator of autonomous application for Photovoltaic System and estimate of a model of autonomous kit with electrochemical storage and autonomous kit over the sun. Using the parameter which is the maximum power accompanied by the efficiency of the photovoltaic with the architectural phases of the DC-DC converter for the photovoltaic effect. These solar systems present structural modeling using MATLAB/SIMULINK software. Thus, we present the corresponding connection stage between the GPV, the MPPT regulator, the solar battery and the circuit breaker. The new technologies of the future are the use of economic solutions using renewable energies. The only one that allows the execution from the point of view of maximum power of the PV module whatever the irradiance of the temperature, the connection of a DC / DC boost converter in a photovoltaic installation at the output of the panel could be a good solution to boost these characteristics. The progress of power electronics in this energy supply specialty, allows us to better manage our work on isolated site in the environment. The essential parameter is the DC and AC load. We simulated and compared the different transfer topologies to achieve the best optimization and energy produced solution.

To reduce construction costs and energy consumed in the heating and air conditioning, one of the solutions is to use the fiber to install Compressed Earth Blocks (CEB). The main purpose of this work is to study the effect of using the scrap tyre rubber fiber and the glass fiber on the mechanical properties and behavior of the CEBs. In this context, we used a lime ratio of (12%) and six fiber percentages (0.05, 0.1, 0.15, 0.20, 0.25 and 0.30%) from dry mixture. The results indicate that the compressive and shear strengths increase proportionally with the fiber ratio until a maximum at the ratios 0.15% for the scrap tyre rubber fiber, and 0.20% for the glass fiber, and then begin to decrease. However, the presence of the fiber has a positive impact on the mechanical behavior of the composite. This study also showed that monitoring of increased stress has a positive impact on the different studied characteristics.

Due to the increasing demand of power supply, depletion of fossil fuel sources and expanding environmental pollution concerns, renewable energy sources such as solar energy seems to be a good solution especially for remote areas, where connection to the utility grid is impossible or would require very high costs. This paper presents modeling, control and simulation of a standalone solar system, which consists of a photovoltaic generator connected to a storage battery through a DC-DC boost converter plus a DC-AC inverter to feed AC charges. Firstly, a mathematical modeling of the equivalent electric circuit for each of the system’s components is performed, and then a maximum power point tracker is developed to control the DC-DC boost converter and extract the optimal power from the photovoltaic generator to charge the batteries. Next, a three phase DC/AC inverter is modeled and controlled using pulse width modulation technique. Finally, and in order to show the efficiency and effectiveness of the proposed system, simulation tests under MATLAB Simulink software are performed and discussed.

The enormous growth in the number of buildings in Algeria has negatively affected the energy consumption and the local, regional and global environment. This Growth has a negative impact on the energy balance, as we are consuming a large proportion of export oriented production, which makes Algeria’s future in the field of energy uncertain and uncertain despite the great potential of the country, “the problem of energy security of Algeria”, that the energy situation in our country will be difficult By 2030 and beyond. If the trend still continues, According to the Energy Balance 2018, the Algerian building sector represents about 42% of total energy use. This huge amount of energy consumption has pointed to the need for more energy-efficient policies to reduce this high consumption. The authors presented a careful study of the energy efficiency policy in national buildings and standards and the status of renewable energy in our country, in this paper, facts and figures related to energy consumption in Algerian buildings CO2 emissions were introduced. Current energy Efficiency policies were reviewed, In February 2011; the government adopted an ambitious program for renewable energy and energy efficiency. All public authorities’ attention to the success of this program is mobilized on the basis of a green strategy developed by 2030, unfortunately, this policy encountered difficulties and obstacles, these difficulties are, in particular, the lack of coordination between different sectors and the inadequacy of national technical capacities to provide inadequate current means of financing. Accordingly, it is necessary to develop more efficient strategies in these cases to achieve the government’s goal. The paper concludes by offering possible solutions to overcome the barriers in the implementation of energy building policy in Algeria [1].

This research presents a new nonlinear control algorithm for doubly fed induction generator (DFIG) based wind energy conversion systems. In order to improve decoupled control of powers stator a fuzzy-feedback linearization control technique is designed. The principal idea is to change Hurwitz polynomials by Fuzzy logic control. The adopted method gives better performance compared with the conventional method particularly to the disturbance rejection.

The present study is an attempt to investigate the effect of freeze-thaw cycles on the performance of concrete made with recycled aggregate pavements (RAP), via visual aspect and measure weight loss after 300 cycles of freeze-thaw. The correlation between compressive strength after these cycles and weight loss gives a better resistance for recycled concrete with a high ratio of RAP. The test results showed that the freeze-thaw resistance is influenced directly by the type of recycled aggregates.

Using the standard mathematical model of the doubly fed induction machine (DFIM) operating as a generator (DFIG) in the study of steady-state stability regions. Confirms that DFIGs have extensive steady-state stability regions and Flexibility in control and ability to operate at relatively wide range of speeds using back-to-back converters. The re-search reveals that a DFIG’s stable region is bounded by unstable regions on both the low- and high-speed ends. Simulations have confirmed the eigenvalue predictions of the unstable regions.

Provided by the sun, the wind, waterfalls, tides or even the growth of plants, renewable energies cover most of the current energy production with little or no polluting emissions. They contribute to the fight against the greenhouse effect and CO2 emissions into the atmosphere, it can consider as an economical and sustainable source of energy, the most known one called solar photovoltaic (PV) energy; PV energy is an inexhaustible green energy that represents an alternative source of energy. This energy is increasingly applied in different areas, ranging from residential and commercial installations to space systems, this type of energy offers many advantages such as the absence of pollution, it is noiseless, easy to install, and requires a short period of time of construction. This paper proposes and discusses the application of field oriented controlled induction motor supplied by PV generator. To track the maximum power point, the algorithm proposed in this work replace traditional one named P&O by fuzzy logic type-2 method.

We have numerically studied the optical intersubband absorption in double barriers of resonant tunneling superlattice based on GaAs/GaAlAs quantum wells as a function of the wavelength of the radiation for different values of voltage and well width. Both eigenenergy and wavefunction were calculated using the exact Airy functions formalism and the transfer matrix method. Our results show that the absorption coefficient contains tow peaks when augmentation of the voltage. Our study shows important role of absorption coefficient in performances of quantum well structures and superlattices.

The electrical structure integrates a spiral rotor induction machine with back-to-back three phase power converter bridges between its rotor and the grid. In the presented design, the so-called vector control theory is theoretical, in order to streamline the electrical equations. The proposed control scheme uses stator flux-oriented vector control for the rotor side converter connection control and grid voltage vector control for the grid side converter bridge control. The stability analysis of the proposed sliding mode controller under disturbances and parameter uncertainties is delivered using the Lyapunov permanence concept. Lastly simulated results show, on the one hand, that the proposed controller provides high-performance dynamic appearances, and on the other needle, that this scheme is robust with respect to the uncertainties that usually appear in the real systems.

This paper presents a comparison of two strategies of estimation the state of charge (SOC) for Lithium-ion battery. Since the SOC cannot be directly measured, the extended Kalman filter (EKF) and modified sliding mode observer (SMO) algorithms were applied and compared to investigate the convergence, tracking accuracy and robust estimation against uncertainties. First-order Thevenin electrical circuit model (ECM) has been established to capture the dynamics of the battery and its parameters were extracted from experiment. Both algorisms are evaluated by two current profiles to show the efficiency of each one. The comparison results show the effectiveness of SMO in terms of execution time, robust estimation and capability of tracking in SOC estimation.

The inverter is an extremely important element in photovoltaic systems, so its surveillance is necessary for the continuity and stability of PV systems. The main aim of this paper is to improve the availability of inverters used in photovoltaic installations by developing fast, efficient and reliable fault diagnosis methods adapted to the installation to make sure the good functioning of the system with good performance, with or without the presence of short-circuit fault. To diagnose a short-circuit fault in the inverter, we used two methods; the first method is the frequency response analysis (FRA), in this case, the inverter is represented by RLC network identified by transfer functions which depend on the frequency, therefore the slightest change in the configuration of the RLC network generates a variation in the impedance of the latter and thus a shift in the transfer function. The FRA approach allows the detection of changes in the transfer function due to defects that may occur during the manufacture or operation of the inverter; the second method is Fast Fourier Analysis Transform (FFT), this method is used to visualize the spectrum of the signals at the output of the inverter at high frequencies.

The production of energy solar by photovoltaic systems depend on the climatic conditions, it is very variable and unexpected. That is why it should be necessary to think how to preserve this energy for later when we need it especially during the night and the days without sun. In this work, an experimental study on the charge and discharge of Electrochemical Storage by a Photovoltaic Field. The installed peaked power is 113 WC and 5% efficiency for load and unloads operation of the installation

Wind speed forecasts are needed for a variety of applications, like satellite launching, aviation, planning of construction, prediction of output power from wind turbines, etc. In this study, an artificial intelligence approach, namely Artificial Neural Networks (ANNs) has been applied to predict the distribution of daily wind speed at height of the 10 m of the target location using the data of neighboring locations. The study includes five regions situated at the southeast of Algeria. The data of four regions (namely Biskra, Ghardaia, Ouargla and Khenchela) have been used for training the ANN model. Thereafter, the wind speed distribution in El Oued region has been predicted. The logistic sigmoid transfer function has been used as an activation function for the hidden layer. The neurons number in the hidden layer has been selected numerically using several tests. A comparison between predicted results and actual data from NASA showed good agreements, in which the root mean square error (RMSE) is less than 1.

This work is a contribution to the search to limit the effects of this phenomenon, which has a problem of harmful effect on flora and fauna. The latter consists of the adsorption of an agricultural pesticide: Acetamiprid on a natural material: granulated activated carbon (GAC) and the granulated animal bone (cattle bone). This work is therefore a comparative study of the retention capacity of these natural biomaterials in order to limit the effects of this type of pollutants. Two natural adsorbents: industrial activated carbon and animal bone carbon: the latter is prepared in the laboratory. The results showed a similarity in the physicochemical characteristics of the two carbons: the maximum yield (or equilibrium of adsorption) is similar for both: equilibrium is obtained after seven days. The equilibrium isotherm shows that the Freundlich equation gave acceptable values for each animal coal and the industrial. The equilibrium isotherm equation check of Freundlich gave a values (n = 0.854; K = 1.746) for animal coal and (n = 0.985; K = 1.798) for industrial coal. The curves giving the adsorption isotherms show that these are of the Freundlich type.

The purpose of this work is to conduct a numerical simulation in order to predict the thermal performance of a shallow solar pond operating under the batch method to extract heat, the pond is equipped with two glass covers to enhance global warming, and the bottom of the pond is painted in black in order to increase the absorption of solar radiation. the pond has also been thermally insulated by wrapping it with polystyrene from the sides and bottom in order to reduce thermal loss, based on the solution of the differential equation resulting from the thermal balance equations of the pond and using the climatic conditions of the city of Medea and that's on date 18/08/2019, a computer program is developed using MATLAB software and the results were presented and discussed.

The aim of this research paper is to perform a numerical simulation of a flat plate solar collector (FPSC) operating under the open cycle of heat extraction in order to predict its thermal performance, FPSC is made of 1 (m2) galvanized material. Also equipped with a heat exchanger made of copper material, an absorber plate made of galvanized material painted in black is placed to enhance the absorption of solar radiation over the heat exchanger. The FPSC is coated with insulation material from the sides and from the bottom and it is provided with two glass covers in order to reduce thermal loss, using MATLAB software and using climatic conditions in Medea, on 10/08/2019, a computer program was developed to predict FPSC thermal performance from 00:00 to 00:00 the next day and the results were presented and discussed.

This work reports a discussion about hydrogen diffusion in n+pp+ polysilicon solar cells following analysis of both dopant deactivation and defects passivation. To do this, we performed plasma hydrogenation on poly- and mono-silicon solar cells to witness, respectively, the evolution of the open-circuit voltage (Voc) and the boron activation profile. The results obtained show clearly that Voc improves as the microwave plasma power increases. Nevertheless, the measured values are much higher for a less doped phosphorus emitters, which confirms that the hydrogen diffusion in the bulk of silicon is more prevented as well as the level of doping is high. However, the tendency of the open circuit-voltage values to saturation at high microwave plasma powers indicates that hydrogen can also produce new defects in polysilicon. This last observation has been well verified on monosilicon n+p solar cells. Also, hydrogen neutralizes boron and generates a concentration gradient between the boundary of the space charge zone and the depth of the p base region. As a result, we have admitted the existence of an electric field that encourages deep hydrogen diffusion atoms in the bulk of polysilicon. Moreover, the appropriate analysis of these results allowed us to propose a credible mechanism for hydrogen diffusion in polysilicon solar cells.

In this paper, we present results obtained by annealing Cu In0.7Ga0.3Se2 (CIGS) thin films in Argon atmosphere, using photoacoustic spectroscopy technique (PAS).CIGS thin films were deposited on SLG substrate by close-spaced vapour transport technique (CSVT) at substrate temperature of 500 °C. The CIGS thin film was polycrystalline with a thickness about 3 µm, and the conductivity was p-type. CIGS Absorbers was characterized by X-ray diffraction (XRD), scanning electron micrograph (SEM), energy dispersive spectroscopy (EDS) and electrode probe. Defect state modifications were investigated by PAS measurements at room temperature during the annealing process under argon atmosphere.

This paper aims to study and simulate the control of a wind turbine based on a double star asynchronous generator (GASDS) for their many advantages: high reliability,the power segmentation and the minimization of the torque waves and the rotor leaks; to control the energy production of this conversion chain, the mechanical power generated should be optimised. ensuring maximum power capture with the MPPT strategy (Maximum Power Point Tracking) for different wind speeds. For this purpose a control by fuzzy logic FLC associated with the vector control by orientation of the rotor flux FOC of the GASDS has been particularly described in order to improve system performance and better trajectory tracking in the case of the variant wind speed systems.

Photovoltaic conversion is the direct transformation of Photonic solar energy into Continuous electrical energy (DC). The problem is to know how to exploit the materials capable of this process with very profitable conversion efficiency. The materials of columns III–V of the periodic table and their alloys are very attractive because they offer great flexibility in the energy of the band gap while being adapted to their lattice parameters which are provided with better physical, electrical and mechanical properties. In this study, we proposed to simulate numerically by the AMPS 1D interface a model of a nnpp + hetero junction solar cell based on InGaP/GaAs with a BSF highly doped back layer and a front with a large band gap. The optimal configuration of this cell shows an efficiency of 28.817% under the AM1.5G spectrum and one sun.

The work presented is a contribution on power management of standalone hybrid electric generation system based on renewable energy sources. In this system, a photovoltaic and wind turbine generators are chosen as principals sources. A diesel generator is used as secondary source. A pack of batteries is used for stocking a surplus energy. A parallel DC bus collection of power is chosen for distribution system. Each source is connected via power converter. The models of major components included in the installation are presented. Based on these models, the proposed power management algorithm of the autonomous hybrid system is developed. For validation of the proposed algorithm, simulation results of the whole system are presented.

The Fe doped ZnO thin films were prepared by sol-gel method assisted spin coating technique using Zn (CH3COO)2 2H2O and FeCl3.6H2O precursors as sources of Zn and Fe. Influence of iron doping into ZnO thin films were investigated by X-ray diffraction (XRD) and optical transmittance. The band gap energy and the structural parameters viz. lattice constants, average crystallite size, dislocation density stress and strain of the films were calculated. The X-ray analysis revealed that polycrystalline ZnO thin films crystallizing in the wurtzite structure and with preferred orientation along [002] direction were obtained. The average crystallite size increases with Fe concentration reaching a maximum value 21.4 nm for a concentration of 5%. The optical band gap energy of the films is found to decrease from 3.42 to 3.15 eV with increase of Fe concentration.

This paper presents the sliding mode control (SMC) of a Voltage Source Converter in High Voltage Direct Current transmission system (VSC-HVDC) application. The sliding mode control device provides desirable advantages such as high tracking precision, strong dynamic response and reasonable robustness. The proposed control scheme was evaluated by simulation using Matlab software. The analysis of the results demonstrates the effectiveness of the proposed control strategy. It can improve the performances and maintain the reliability of the studied system.

Among various methods used for the synthesis of TiO2 thin films, we have chosen the sol–gel route, which is widely used today due to its simplicity and low cost. The precursors solutions have been synthesized and doped at 10% at. with manganese, nickel and copper. The films were deposited using dip-coating technique with a constant withdraw speed on glass substrates. The UV–visible spectroscopy was applied to study the effect of doping on the optoelectronic properties of the material.

This work aims to study the possibility of recycling floor tile waste as fine aggregate in the manufacturing of flowable sand concrete (FSC). For this; the sand is substituted with floor tile waste at different percentages (0, 10, 20, 30, 40, 50 and 60%). The mini-slump flow diameter and density of fresh mixes, as well as compressive and flexural strength in hardened state of the different FSC mixes, are determined, analyzed and compared with control concrete. The obtained results show that some physical and mechanical characteristics of FSC mixes with floor tile waste are better than those of conventional flowable sand concrete. This study, as well, insures that reusing floor tile wastes in FSC gives a positive approach to reduce the cost of materials and solve some environmental problems.

Scientific knowledge in the field of magnetic refrigeration in the vicinity of room temperature has aroused great interest in recent years because of its high energy efficiency, while having a low environmental impact, which is why much work is being done on materials to advance and control the entire chain from material to application through characterization. Quaternary Heusler alloys have received considerable attention in the development of magnetic materials to study, design and develop magnetic refrigeration systems near room temperature. The aim of this study is to optimize the thermal and structural behavior of a quaternary NiCoMnSn alloy for the concentrations x = 0, 1/4, 1/2, and 3/4; using CASTEP numerical modeling code based on quantum mechanics and density functional theory for the solution of the Schrodinger equation. The main predictors obtained allow us to state that the structure in the ferromagnetic state is more stable; and this makes this material a good candidate for different applications.

This paper deals with an autonomous system photovoltaic generator (PV) with energy storage to supply three-phase load. In effect, a three level NPC Power inverter in introduced to improve the output voltages of the autonomous system. For this, each PV generator has supplied one DC bus of the inverter. However, the both midpoint DC bus of the NPC inverter has shared the same pack of batteries.

The study examined samples of soils and sediment (dumps) in areas exposed to the zinc ore enrichment of the Chaabet-al-Hamra deposit, by their color according to the Munsell color scale, determined the content of heavy metals and other elements, analysis of mercury, mineral composition, PH. It is shown that almost the entire studied territory, except for a small area in the foothills, has an excess of normative indicators for zinc, lead and cadmium. Copper contamination is less significant and is localized mainly on the territory of the plant itself.

This article focuses on the technical and economic feasibility of an autonomous solar pumping system to supply water to a gravity tank for irrigation of an experimental nursery with an area of 01 hectare located in the region of Ouled Fares (W. Chlef). This tank can guarantee an autonomy of 04 days, or 6 kW of energy, and the electricity needs of a water pump are around 1.5 kWh/d. The pump re-quires a nominal power of 0.75 kW and must operate at 100% of this power. The HOMER software was used to simulate the autonomous system in order to determine the size and number of PV to install and perform the optimal configuration. Data relating to global solar radiation and air temperature were collected between January 1, 2018 and December 31, 2018 at a weather station installed in the study area. The study concluded that the proposed PV system is the most economical. It can produce 3020 kWh/year with an energy cost (COE) of $0.814/kWh and this system meets the needs of the chosen solar pump which are around 512 kWh/year. In addition, the comparison showed that the autonomous system is the best choice compared to the connection to the conventional network with COE $0.047/kWh when the connection distance exceeds 0.126 km.

Due to the nonlinear electrical characteristics of photovoltaic (PV) generators, the performance and efficiency of such systems can be improved by forcing it to operate at its maximum power point (MPP). In this article, we have proposed an adaptive strategy to achieve maximum power point tracking (MPPT) using an artificial neural network (ANN) approach. ANN control based on neural network learning database is used to control the boost converter fed by an autonomous photovoltaic generator (PVG). The obtained results show that the ANN-MPPT control provides low oscillations and shows good performances around the maximum power point of the PVG compared to the Classical MPPT algorithms such as perturb and observe (P&O).

In this paper, The techno-economic performances of Parabolic Trough solar thermal plant (PT) were evaluated with minimum levelized cost of electricity (LCOE) as objectives, at three different locations in Algeria (Hassi R’mel, Tamanrasset and InSalah) using the System Advisor Model (SAM) software. In this study, the size of the solar field, the Fossil Fill Fraction of backup system and Full Load Hours of storage are optimized using the concept of solar multiple. Moreover, different models, technologies and scenarios are presented. From results, Parabolic Trough Solar Plant with 25% of backup system and 7.5 h of storage is the best and optimum solution under Algerian climates. Tamanrasset is the suitable location to Parabolic Trough solar thermal plant in Algeria.

This paper aims to analyze a hybrid photovoltaic system for production of electrical energy associated with a storage system to be employed in an isolated site. A methodology has been adapted using the HOMER software to study this type of system. The results show a good and accurate simulation of the energy behavior of the complete system and this type of system operates with a high reliability and a technical, economical and ecological profitability in comparison with the conventional solutions. These results can be used to give answers to many questions about this type of installation and help manufacturers to make the right decisions.

The power generated by wind turbines is considered as to be clean. Wind energy is becoming a priority, among renewable energies, it is considered as a mature and most economical technology after hydroelectricity. The aim of this work is to develop a method for optimizing the aerodynamics shape of the wind turbine blade. An optimization approach will be adopted and applied. To have the shape that will maximize the production of the power of the wind turbine. So our objective is to design the optimal wind turbine blade shape by selecting the optimal airfoil at each rib station along the spanwise direction. The steps of this work consists in developing an optimization method by means of Proper Generalized Decomposition as a calculation tool through the implementation of PGD code on MATLAB starting from Blade Element Theory, that is to say our sought solution is to maximize the power at each rib station, so we will obtain the formulation of the power based on the separation of the coordinates, our coordinates here will be the relative air velocity, chord, the radius r, and the coefficient of the tangential force Ct. With this formulation we will be able to designate which values of Ct generate a maximum power, what will allow us to pick up the best airfoil. So through this method we will open the possibility on the integration of any desired control parameter and monitor the power, to have in the end several optimal models of wind turbine blades.

This paper describes the study of an electrical system composed of a photovoltaic generator connected to the electrical network. To improve the quality of energy, the Direct Power Control (DPC) technique is used to control the active power produced by the photovoltaic generator and injected into the electrical network. Thus, the compensation and the elimination of the harmonic currents present on the network given by a non-linear load. This system consists of a photovoltaic generator as the main renewable source, connected to a DC-DC converter controlled by the MPPT (Maximum Power Point Tracking) technique. The connection to the electrical network is ensured by a DC-AC converter. The simulation of the developed system under the Matlab environment showed the robustness of the proposed algorithm.

Energy storage is a very important operation in continuously operating systems, such as telecommunications systems, embedded systems and power systems. Energy storage can be performed by various means such as batteries and super capacitors. In our work, we used KMeans Fuzzy Logic to classify the Energies values associates to capacitances C of the planar capacitors as a function of the relative permittivity εr, the thickness d and the dimensioning (Width and Length) of the capacitor plates and as a function of the maximum desired charge Qmax. The results of simulation will be better and more satisfying if the databases are richer and good.

In this work, an attempt is made to design an optimal wind/PV/diesel hybrid power system for a village of Ghardaia, Algeria. The aim of this paper is the optimization using grey wolf optimizer (GWO) of a hybrid wind/solar/diesel system applied in term of technical and economic feasibility by simulation using matlab software.

This paper proposes a robust method of maximum power point tracking using a type-2 fuzzy logic controller for photovoltaic systems. The maximum power point tracking controller receives solar irradiation and photovoltaic cell temperature as inputs, and estimated the optimum duty cycle corresponding to maximum power as output. The new method gives a good maximum power operation of any photovoltaic array under different conditions such as changing solar irradiation and PV cell temperature. From the simulation results, the Type-2 Fuzzy logic controller can deliver more power than other different methods in literature.

The reliability and stability of the electricity production systems operation from renewable and sustainable resources require an important task which is the monitoring systems. In this research work, a software application is developed for monitoring and evaluating the performance of the installed PV systems in renewable energy research unit in the Saharan region (URERMS) Adrar. This software application is used with the existing data acquisition system which contain the data logger unit and the sensors to measure the meteorological and electrical parameters of the PV systems. The structure of developed software application running on the desktop PC and the used data acquisition system to monitor the PV station are detailed.

This paper describes the photovoltaic system connected to the electrical grid. The document begins with a description of this system, a definition and a brief overview of each component used in this system were provided and they are taken separately. The system is simulated with precise climatic conditions and four modes of operation. The results of the simulation illustrate how the change of a solar radiation can affect the output power of the PV system, it’s also show the conversions of the power of the photovoltaic system with the electric grid.

In today's technology, using static compensators to maintain stability is gaining trust every day. In this article, Static Variables Compensator (SVC) combined with a Static Synchronous Compensator (STACOM) form the ingredients of voltage stability system, more precisely to keep the voltage factor as close as possible to the unity network (1 PU). After these device’ deployment, the improved stability of the hybrid PV-Wind system efficiency is determined through the calculation of power flow and compared to the calculated power flow before the integration of these devices. The motivation for this operation is to find the contrast and evaluate the different devices’ roles in the subject system. The subject system is formed with 14 bus bars, for which their contribution to the improvement of the stability, altered by each device. As a result, and after analysis a considerable reduction of drops of the voltage of the bus bar yielding appreciated voltage control.

The effect of the oxygen flow rate on the structural and optical properties of ZnO films was investigated. Zinc oxide films were deposited Si (100) wafers and glass substrate by a DC magnetron sputtering technique using Zn targets in an Ar/O2 mixture atmosphere. The oxygen content was changed from 10 to 30 sccm. The different properties were analyzed by using XRD, SEM, profilometer, and UV-visible. The evolution of optical and structural proprieties as O2 was investigated by XRD, Profilometer, FESEM and UV-visible. O2 increasing lead to improve ZnO crystallinity in wirtzite phase and the films present (002) preferential orientation along the c-axis. ZnO films present a significant improvement in band gap that present an enlargement from 3.13 to 3.30 eV due to the crystallite size increase from 22 to 30 nm.

In this paper, we present a first-principles studies of two paraelectric perovskites KNbO3 and CaTiO3 in which we give a classical characterization, and add the photoconductive property, they can be used as optoelectronic compounds at furnace-like temperatures. We give also the photoconductive property of KTaO3 and SrTiO3 studied in previous article (Benrekia et al. in Phys. B 407:2632–2636, 2012 [1]) they can be used at cryogenic temperatures. These characterizations are done by the density functional theory (DFT) within the PBE and PBEsol and GW by the VASP software. The characterization concerns the structural, electronic, and optical properties. The DFT band gap energies defaults are corrected by the GW band gap energies and used to correct the optical properties of those compounds. The results are in line with the experimental values and theoretical results.

In this research, thermal investigation was performed on a solar chimney power plant system. 2D numerical model was developed using RANS equations with k-epsilon turbulence model to investigate air flow behavior in the system. The effects of chimney height and heat flux on the flow parameters were analyzed. The results of this study showed that the chimney height and heat flux are important factors for enhancement the performance of solar chimney power plant system.

Nowadays the largest part of installed solar thermal power plants are based on the Parabolic Trough solar Collector (PTC). The efforts in R&D areas for the development of new components and materials for this kind of collectors make parabolic trough technology a mature and clean solution for electricity generation. The distribution of incident solar rays around the absorber tube constitutes a key element in the study of optical and thermal performances of PTCs. In this paper, we propose to study the effect of rim angle on the performance of the PTC taking into account the non-uniformity of solar flux. Firstly, a detailed optical model based on Monte Carlo Ray Tracing method (MCRT) has been developed using Matlab software. The simulations have been carried out through the LS2 collector of Solar Thermal Electric Generation System (SEGS). Then, the results of the MCRT code has been coupled with Finite Volume Method (FVM) using ANSYS software to analyze the heat flux distribution on the absorber tube under some rim angle values.

The present study investigates the thermal performances of two ISCC configurations which one integrates a parabolic trough collector technology with a conventional combined cycle (ISCC-PTC) and the other one integrates a solar tower power (ISCC-ST) with more attention is paid to solar electric conversion. The results have shown high thermal performances for both ISCC systems while the ISCC-ST exhibits a constant value of 0.21 of solar to electric efficiency conversion for the two selected days but the ISCC-PTC value is 0.16 for the spring day which is 31% lesser than that one of ISCC-ST. This investigation allows concluding that the configuration of ISCC-ST integrating a solar tower power is a good option for integration of solar energy into a conventional combined cycle.

Turbulence is a phenomenon associated with the flow of wind in wind farms. It has a significant effect on the performance of wind turbines, causes a strong load on the blades and modifies the evolution of the profile of the wind speed in the increasing wake. In order to investigate this phenomenon and describe in a much more precise way the effect of wind turbulence on the produced power of a wind turbine, we present in this work, a study which aims at the effect of turbulence on a wind turbine in downstream in the wake of another front wind turbine, for a given wind farm. This study is based on the use of the complete Ishihara wake model which takes into account the ambient and generated wind turbulence and on the input of data and characteristics of the ENERCON E2 commercial wind turbine. The simulation results obtained from the power developed with turbulence have been presented and compared to those without turbulence.

This paper discusses a control strategy that allows maximum energy extraction from a variable speed wind power conversion system based on a sliding mode extremum seeking control scheme. The main purpose is to supply 230 V/60 Hz domestic appliances through a single-phase inverter. The required power can be effectively supplied by the proposed wind turbine with the proposed MPPT controller. This MPPT system allows to changes the VDC reference signal (VdcRef) of the inverter VDC regulator. A second controller regulates the DC link voltage to its reference value and the third controller regulates active and reactive grid current components. The active current reference is the output of the DC voltage controller. The simulation of the system operating in variable wind conditions shows the performance of the developed MPPT controller based on the sliding mode extremum seeking control algorithm.

Electrocaloric cooling based on electrocaloric materials (ferroelectrics materials) is an environmentally friendly refrigeration technology with high cooling power and tempurature span. Electrocaloic refrigeration is based on the ECE (electrocaloric effect); The electrocaloric effect is an intrinsic property of certain materials having the particularity of being ferroelectric (ceramics, single crystals and polymers).The principle of the electrocaloric effect is based on an adiabatic and reversible polarization/depolarization of the electric dipoles under the action of an electric field.Thus, the application and stopping of the electric field induces an electrocaloric cooling cycle composed of four stages. In this paper, we studied the effect of regenerator geometry (parallel plates, packed bed (cylinder) and perforated plates) in an electrocaloric refrigeration systems.

This paper aims to investigate the structural, electronic, optical and thermoelectric properties of lead sulfide using the first principles calculations. The exchange–correlation potential is treated by two approximations, the local density approximation (LDA) and the generalized gradient approximation (GGA) to calculate the structural and electronic properties. The optical and thermoelectric properties of PbS sample are well predicted by GGA. The calculated band structure and density of states (DOS) show that lead sulfide is a semiconductor with gap energy of 0.082 and 0.47 eV for LDA and GGA respectively. The real and imaginary parts of dielectric function, refractive index, reflectivity and absorption coefficient are discussed in detail, where the results obtained are predictive and serve as good references for future experimental work. Finally, temperature dependent thermoelectric properties like electrical and thermal conductivity, Seebeck coefficient and power factor were calculated in detail by employing the Boltzmann transport theory under the BoltzTraP code. The PbS compound has a large power factor at high temperature reaches 2.51 × 1011 (W/mK2 s) with a positive Seebeck coefficient which indicates that lead sulfide is an intrinsic p-type semiconductor, and the major carrier is predominated by holes. Therefore, it reveals that PbS can be used as promising materials for high potential thermoelectric.

This paper represents a comparison study between two fluids methanol and methane, to produce hydrogen from the procedure of steam reforming. Fluent was used for simulations of Methanol and Methane steam reforming. The aim of this work is to show the evolution of heat and mass transfers inside the reactors and their efficiencies. The results showed in the methanol steam reforming part; the consumptions of the main reactant CH3OH and productions of the base element H2. The methanol reformer efficiency is near to 42%, and in the methane steam reforming part; the consumptions of CH4 and productions of H2. Also, the methane reformer efficiency is more than 46%.