Hussein A. Kazem

A Novel Numerical Algorithm for Optimal Sizing of a Photovoltaic/Wind/Diesel Generator/Battery Microgrid Using Loss of Load Probability Index

This paper presents a method for determining optimal sizes of PV array, wind turbine, diesel generator, and storage battery installed in a building integrated system. The objective of the proposed optimization is to design the system that can supply a building load demand at minimum cost and maximum availability. The mathematical models for the system components as well as meteorological variables such as solar energy, temperature, and wind speed are employed for this purpose. Moreover, the results showed that the optimum sizing ratios (the daily energy generated by the source to the daily energy demand) for the PV array, wind turbine, diesel generator, and battery for a system located in Sohar, Oman, are 0.737, 0.46, 0.22, and 0.17, respectively. A case study represented by a system consisting of 30 kWp PV array (36%), 18 kWp wind farm (55%), and 5 kVA diesel generator (9%) is presented. This system is supposed to power a 200 kWh/day load demand. It is found that the generated energy share of the PV array, wind farm, and diesel generator is 36%, 55%, and 9%, respectively, while the cost of energy is 0.17 USD/kWh.

Harmonic Mitigation Techniques Applied to Power Distribution Networks

A growing number of harmonic mitigation techniques are now available including active and passive methods, and the selection of the best-suited technique for a particular case can be a complicated decision-making process. The performance of some of these techniques is largely dependent on system conditions, while others require extensive system analysis to prevent resonance problems and capacitor failure. A classification of the various available harmonic mitigation techniques is presented in this paper aimed at presenting a review of harmonic mitigation methods to researchers, designers, and engineers dealing with power distribution systems.

Design and assessment of solar concentrator distillating system using phase change materials (PCM) suitable for desertic weathers

AbstractA desertic region always suffers from a lack of fresh water in a large portion of its area. In these areas, available water from swamps or ground water wells is brackish water, and it must be purified or distillated. In this paper, we introduce a simple distillation system accompanied with a concentrating unit. This system was assembled and installed with very low costs. Also, paraffin wax was used in this study as phase change materials to absorb heat from the heated water. The concentrating system, which consists of a dish accompanied by a drum as a storage device and pipes assembly fixed at dish focal, was used to heat brackish water. The conical distiller was fabricated to contain PCM under its base to increase the stored energy. Tests were conducted at Baghdad, Iraqi wintertime 2013–2014. The study declares that this system is suitable to desert weathers with acceptable productivity compared with other existing systems. Adding PCM to the concentrating distillation system increased system work...

Modeling and Characterization of a Photovoltaic Array Based on Actual Performance Using Cascade-Forward Back Propagation Artificial Neural Network

This paper proposes a novel prediction model for photovoltaic (PV) system output current. The proposed model is based on cascade-forward back propagation artificial neural network (CFNN) with two inputs and one output. The inputs are solar radiation and ambient temperature, while the output is output current. Two years of experimental data for a 1.4 kWp PV system are utilized in this research. The monitored performance is recorded every 2 s in order to consider the uncertainty of the system’s output current. A comparison between the proposed model and other empirical and statistical models is done in this paper as well. Moreover, the ability of the proposed model to predict performance with high uncertainty rate is validated. Three statistical values are used to evaluate the accuracy of the proposed model, namely, mean absolute percentage error (MAPE), mean bias error (MBE), and root mean square error (RMSE). These values are used to measure the deviation between the actual and the predicted data in order to judge the accuracy of the proposed model. A simple estimation of the deviation between the measured value and the predicted value with respect to the measured value is first given by MAPE. After that, the average deviation of the predicted values from measured data is estimated by MBE in order to indicate the amount of the overestimation/underestimation in the predicted values. Third, the ability of predicting future records is validated by RMSE, which represents the variation of the predicted data around the measured data. Eventually, the percentage of MBE and RMSE is calculated with respect to the average value of the output current so as to present better understating of model’s accuracy. The results show that the MAPE, MBE, and RMSE of the proposed model are 7.08%, −0.21 A (−4.98%), and 0.315 A (7.5%), respectively. In addition to that, the proposed model exceeds the other models in terms of prediction accuracy.

An Improved Method of Passive Input Current Waveshaping for Single-Phase Rectifier

This paper presents an improved passive input current waveshaping method for single-phase rectifiers (improved method-2). The simulation results show that the improved method can further lower the input current components and THDi of a single-phase diode rectifier as compared with the passive current waveshaping method by Ji Yanchao (improved method-1) and by P. D. Ziogas (novel method). The relevant input current and voltage waveforms, the input current total harmonic distortion and the input power factor value are derived from the computer simulation or theoretical analysis. A design example is provided and simulation results have been verified on 500 mW experimental models.

Techno-economical assessment of grid connected PV/T using nanoparticles and water as base-fluid systems in Malaysia

ABSTRACT In this study, the techno-economic assessment of GCPVT with nanofluid has been investigated based on theoretical and experimental work in Malaysia. The productivity and utilisation of the PV have been investigated using yield and capacity factors (CFs), respectively. Also, the cost of energy and payback period has been calculated. The system installed, tested, and data have been collected. Evaluation of the system in terms of current, voltage, power and efficiency are presented. The average daily ambient temperature and total global solar energy in Kuala Lumpur are 38.89°C and 4062 Wh/m2, respectively. MATLAB software is used to analyse the measured data. The assessment results show that the GCPVT system has annual yield factor, CF, the cost of energy; payback period, and efficiency are (128.34–183.75) kWh/kWp, (17.82–25.52)%, 0.196 USD/kWh, 7–8 years and 9.1%, respectively. This study indicates that the GCPVT system with nanofluid improved the PV technical and economic performance. GRAPHICAL ABSTRACT

Optimization of photovoltaic modules tilt angle for Oman

This paper presents a method for optimization of photovoltaic modules tilt angle for Sohar, Oman. Numerical method for optimization of the PV module tilt angle, is implemented using MATLAB and hourly meteorological data and load demand. The results show that for Sohar zone the tilt angle of a PV array must be adjusted twice a year where the PV array must be slanted at 49 degrees in the period of 21/0921/03 (n=255-81), while it must be horizontal (tilt angle is zero) in the period of 21/03-21/09 (n=81-255). This adjustment practice gains the energy collected by a PV array by 24.6%.This paper contains important information for those who are interested in photovoltaic system investment in Oman.

Evaluation of the Economic and Environmental Aspects of Using Photovoltaic Water Pumping System

Desertic areas suffer from a lack of water, whether for drinking or irrigation. Moreover, the wide speared of these areas makes connecting it with electricity lines tough and expensive. Stand-alone Photovoltaic (PV) array showed it effectiveness in solving these problems in many places of the world. In this paper, the Software HOMER and REPS.OM used as numerical methods to design a PV water pumping system suitable for Omani rural and desertic areas depending on hourly meteorological data. The optimum design used to supply an irrigation pumping system. The selected system capital cost as well as its energy costs compared to diesel generator and systems in literature. The comparison shows that the proposed system results in a proper cost of energy and lower environmental pollution.

Levelized electricity cost for photovoltaic system in Sohar-Oman

Solar Photovoltaic (PV) is suitable for electricity generation in stand-alone power system in rural desert areas in Oman, where solar energy resources are the highest. In this research a 3080 W solar PV system have been designed to investigate the PV performance. The average daily load demand is 4.7 kWh/day and details loads are listed. The energy that is generated by the PV technology has been estimated using real weather data for Sohar-Oman. Basic principles of designing a quality PV system have been used to design the system. HOMER software is used to levelize, analysis and estimate the life cycle of the PV system. The cost of PV system energy is calculated with different sizes for PV, battery and converter. The results indicate that the solar energy utilization is an attractive option with initial cost, net present cost of the system, and energy cost are 7,160

Effect of Shadows on the Performance of Solar Photovoltaic

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