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In unpredictable weather circumstances, a maximum power point tracking (MPPT) approach is critical for ensuring maximum photovoltaic (PV) output power is extracted. In this paper, we will compare the incremental conductance algorithm (IC), perturb and observe (p&o), and fuzzy logic controller (FLC) as maximum power point tracking (MPPT) techniques. The three algorithms were used on a photovoltaic energy conversion system that was linked to a grid. The suggested methodologies investigate the photovoltaic (PV) system's solar energy conversion performance under various irradiance and temperature circumstances. Lastly, a performance comparison between IC, P O, and FLC has been performed, demonstrating the superiority of the fuzzy controller over the other approaches. FLC converts photovoltaic electricity readily, reducing fluctuations, and it responds quickly to variations in solar irradiation (the shading effect). The simulation results demonstrate that the controller using fuzzy logic performs well, allowing the inverter to convert the electricity provided by the solar panels. [ABSTRACT FROM AUTHOR]

Adsorption has been a widely economical way of removing major pollutants from wastewater in latest times. Zn2+ is a severe human and animal life hazard. The adsorption properties of the chitosan-kaolinite (Ch-K) composite prepared by chemical precipitation for Zn2+ uptake from synthetic polluted water were investigated. The Ch-K composite was analyzed by FT-IR, XRD, SEM and TGA. Under the optimum experimental conditions, the minimum beds average diameter of Ch-K composite was 110 µm. A lot of experiments were done to optimize the adsorption parameters such as concentration of adsorbate, dose of adsorbent, pH and time of contact. The results showed that the Zn2+ sorption onto Ch-K composite were mainly dependent on pH and was affected by the temperature. To express the mechanism of adsorption process and the effect of other parameters on the adsorption time, the kinetic and isothermal models were studied. The second-order kinetics and Freundlich model are suitable for the process. Thus, Ch-K composite has been proved as a potential adsorbent for the removal of Zn2+. [ABSTRACT FROM AUTHOR]

All cobalt quantities available are used in the industry but the wastewater containing this heavy metal remains toxic to humans and the aquatic environment. Therefore, more environmentally friendly techniques for cobalt removal are being explored. The present communication presents a study in a batch mode of the effect of Wasif and Bayda clay composites on Cobalt-59 removal from an aqueous solution. The characterization of the clay composites is done using X-ray diffraction (XRD), X-ray fluorescence (XRF), Fourier Transform Infrared Spectroscopy (FT-IR), and Scanning Electron Microscopy (SEM). Subsequently, the clay composites are charged with Cobalt-59 and the adsorption characteristics are investigated with respect to pH, an adsorbent dosage, an initial cobalt concentration, contact time and a temperature. The removal of Cobalt-59 ions increases with the increase of these parameters with the temperature exception. The removal rate is initially high but then decreases to attain an equilibrium at 60 min. 1 g of the composite charged with 125 mgL-1 cobalt ions has an adsorption efficiency of 91.3 % and 56.49 % for the Wasif and Bayda clay composites, respectively. The data fits better the Freundlich isotherm than the Langmuir one. Based on the thermodynamic parameters ΔGo, ΔSo, and ΔHo the adsorption involves essentially a physisorption process for the Wasif clay composite. Herein, an increase of the temperature leads to a decrease of the percentage of Cobalt (II)-59 ions removed. A chemisorption process dominates the Bayda clay composite interaction with Cobalt (II)-59 ions. Here, an increase of the temperature leads to an increase of the removal of Cobalt (II)-59 ions from the aqueous solution. However, the reactions in both cases are spontaneous as ΔGo values are negative. In addition, the reactions involving Wasif and Bayda clay composites are endothermic as ΔHo values are positive. [ABSTRACT FROM AUTHOR]

In this paper, a classic proportional--integral (PI) control strategy as an energy management strategy (EMS) and a microgrid stand-alone power system configuration are proposed to work independently out of grid. The proposed system combines photovoltaics (PVs), fuel cells (FCs), batteries, and supercapacitors (SCs). The system supplies a dump load with its demand power. The system includes DC/DC and DC/AC converters, as well as a maximum power point tracking (MPPT) to maximize the harvested energy from PV array. The system advantages are represented to overcome the problem of each source when used individually and to optimize the hydrogen consumption. The classic PI control strategy is used to control the main system parameters like FC current and the state-of-charge (SOC) for the battery and SC. In order to analyze and monitor the system, it was implemented in the MATLAB/Simulink. The simulation done for fuzzy logic and high frequency decoupling and state machine control strategies to validate the PI classic control strategy. The obtained results confirmed that the system works efficiently as a microgrid system. The results show that the SOC for the battery is kept between 56 and 65.4%, which is considered a proper value for such types of batteries. The DC bus voltage (VDC) is kept within the acceptable level. Moreover, the H2 fuel consumption is 12.1 gm, as the FCs are used as supported sources working with the PV. A big area for improvement is available for cost saving, which suggests the need for further research through system optimization and employing different control strategies. [ABSTRACT FROM AUTHOR]