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Owing to the stochastic behavior of renewable energy activity and the multiple design considerations, the advancement of hybrid renewable energy-based microgrid (HREMG) systems has become a complex task. This study proposes a design optimization algorithm for the long-term operation of an autonomous HREMG along with the optimal system capacities. The investigated energy system comprises photovoltaic panels, wind turbines, diesel generators, and batteries. It aims to energize a remote coastal community with a daily load demand of 400 kWh in Marsa Matruh, Egypt. Since most studies utilize commercial tools in the design optimization procedure, the African vultures optimization approach (AVOA) is developed to find the optimal energy alternative and determine the optimal component's capacity considering achieving the minimum energy cost and loss of power supply probability. Moreover, an adequate energy management strategy is suggested to coordinate the power flow within the energy system in which renewable energy sources are fully penetrated. To check the AVOA robustness and efficacy, its performance is compared with the HOMER Pro most popular commercial tool as well as with new metaheuristic algorithms, namely the grasshopper optimization algorithm (GOA) and Giza pyramid construction (GPC) under the same operating environment. The results revealed that the proposed AVOA achieved superior economic results toward the least net present cost ($346,614) and energy price (0.0947 $/kWh). Moreover, over 20 independent runs, the AVOA showed a better performance in terms of convergence and execution time compared to other tools/algorithms. The obtained findings could be a useful benchmark for researchers in the sizing problem of hybrid energy systems. [ABSTRACT FROM AUTHOR]

The lack of clean water and access to energy are two major obstacles to global sustainable systems. The development of solar photovoltaic (PV) technology gained the attention of water desalination projects due to its cost decline, carbon-free emission, and the on-site energy production. However, studies on in-depth analysis of the performance of these systems remain rare. This study performs a comprehensive a design optimization and seven-factor analysis (energy, exergy, economic, environmental, energoeconomic, exergoeconomic, enviroeconomic - 7E) of a grid-tied PV system powering a large-scale seawater reverse osmosis (SWRO) plant. First, an optimal design model is developed based on real hourly measured data for the SWRO load demand and renewable resources, while considering net energy metering mechanism. The objective function is delineated to diminish the energy cost of the system, concomitant with the imposition of operational constraints. Second, an analytical model is established to perform exergetic calculations for the optimal design. Third, a sensitivity analysis is conducted to show how the model parameters affect the system design and costs. The results show that the optimal system relies on a 4.25 MW solar PV array and a 3.125 MW grid-tied inverter. This configuration reduces the levelized cost of energy by 48.3 % and carbon emissions by 50 % compared to a grid-only system. The implementation of net-metering has also maximized the designed system's revenues to 263,834 $/year. Further, the optimally designed system achieves a lower levelized cost of water (0.2217 $/m3), minimal capacity shortage, and negligible unmet load ratios (0.048 %) despite grid outages. From the exergetic assessment, the proposed system has a high exergy efficiency (9.3 %) which can be achieved despite the high value of the exergy loss. Moreover, the energoeconomic and exergoeconomic indicators have recorded tiny values (3.35E-5 kWh/$ and 0.0311 kWh/$, respectively), which are considered a desired outcome. Notably, a profit of 4285.4$ is achieved through the sale of carbon emissions reduction. The sensitivity analysis revealed an increase in the system's total cost of 4.91 % and 9.36 % and the system's energy cost of 4.91 % and 8.7 % if the energy purchase price raised by 10 % and 20 %, respectively. Also, it indicates that a fall in the electricity sellback rate of 10 % would remarkably raise the system's energy cost by 47.3 %. Finally, reducing the PV-Inverter costs by 15 % would drop the system's net present and energy costs by 51.4 % and 60 %, respectively. Overall, the insights from this study have the potential to expedite the realization of sustainable development goals 6, 7, and 13, particularly in developing nations abundant in solar energy resources. • A design optimization model for a grid-tied solar PV-powered SWRO systems is proposed. • An energetic calculations model for a comprehensive 7E analysis is developed. • Proposed system reduced energy cost to 0.0393$/kWh and water cost to 0.2217$/m3. • Achieved high exergy efficiency (9.3 %) and favorable energy economic and indicators • Sensitivity analysis reveals that lower PV-inverter costs cut energy cost by 60 %. [ABSTRACT FROM AUTHOR]

The superior access to renewable sources in modern power systems increases the fluctuations in system voltage and power. Additionally, the central dilemmas in using renewable energy sources (RESs) are the intermittent nature of and dependence on wind speed and solar irradiance for wind and photovoltaic (PV) systems, respectively. Therefore, utilizing a vigorous and effective energy storage system (ESS) with RESs is crucial to overcoming such challenges and dilemmas. This paper describes the impacts of using a battery storage system (BSS) and superconducting magnetic energy storage (SMES) system on a DC bus microgrid-integrated hybrid solar–wind system. The proposed method employs a combination of BSS and SMES to improve the microgrid stability during different events, such as wind variation, shadow, wind turbine (WT) connection, and sudden PV outage events. Distinct control approaches are proposed to control the system's different components in order to increase overall system stability and power exchange. Both the PV and wind systems are further equipped with unique maximum power point tracking (MPPT) controllers. Additionally, each of the ESSs is controlled using a proposed control method to supervise the interchange of the active power within the system and to keep the DC bus voltage constant during the different examined instabilities. Furthermore, to maintain the load voltage /frequency constant, the prime inverter is controlled using the proposed inverter control unit. The simulation results performed with Matlab/Simulink show that the hybrid BSS + SMES system successfully achieves the main targets, i.e., DC voltage, interchange power, and load voltage/frequency are improved and smoothed out. Moreover, a comparison among three case studies is presented, namely without using ESSs, using the BSS only, and once more using both BSS and SMES systems. The findings prove the efficacy of the proposed control method based on the hybrid BSS + SMES approach over BSS only in preserving the modern power system's stability and reliability during the variable events. [ABSTRACT FROM AUTHOR]

This paper investigates the potential and feasibility of an integrating hybrid renewable power generation system with a large-scale reverse osmosis desalination plant to provide electricity, heat, and water for the New Capital International Airport, Egypt. The proposed energy system contains photovoltaic panels, wind turbine, combined heat-power microturbine generator, diesel generator, batteries, converter, thermal load controller, and a boiler. A comprehensive energy-economic-environmental optimization analysis was performed to optimize energy systems in which 16-feasible solutions were evaluated and compared. The results revealed that the optimal system has the least net present and energy costs by 1.54 M$ and 0.089 $/kWh, respectively, and needs only 1.12 years to recover the invested money. Moreover, the proposed system produces emissions of 59.5% less than the base-case. The optimal system has a negligible unmet load ratio since it has a negligible loss of power supply possibility of 0.0993%. The thermal load controller has a significant impact on reducing the net present cost, cost of energy, emissions, and needed batteries by 52%, 56.4%, 36.5%, and 90%, respectively compared to the base-case. The obtained results are expected to attract large investments in clean energy and water desalination because of the government's challenges in such fields. • Energy-economic-environmental optimization is performed for an airport in the new capital of Egypt. • Prominence is set to provide the airport with the daily need for electricity, heat, and water. • The effect of renewables, TLC, and batteries on the optimal system performance is discussed. • The cost of energy of the optimal system is reached to 0.08 $/kWh with a payback period of 1.2 years. • The proposed system generates 59.5% of CO 2 emission less than the traditional diesel. [ABSTRACT FROM AUTHOR]

• A two-stage multi-attribute analysis method for optimal design of sustainable energy system is proposed. • Different alternatives are optimized based on energy, environmental, economic, and social attributes. • Effect of uncertainty parameters on the designed system structure and cost is examined. • PV-WT-BAT-CONV mini-grid is the most sustainable alternative in El-Qsier urban city, Egypt. • Load growth and battery cost have high impacts on investment decision rather than RE resources. This paper proposes a two-stage multi-attribute analysis method in conceptualizing the feasible electrification strategy with optimal capacities for a mid-rise building situated in El-Qsier urban city, Egypt. The proposed model measures the implementation practicability of hybrid mini-grid against stand-alone diesel and the utility grid extension systems. The model takes into consideration, simultaneously, a total of 12 attributes covering technical, economic, environmental, and socio-political sustainability aspects. First, an accurate Energy-Enviro-Economic (3E) optimization analysis is performed to determine the set of feasible configurations using HOMER Pro software. Second, a Multi-Attribute Decision Making (MADM) model is established based on AHP, TOPSIS, VIKOR, CODAS, WASPAS methods to identify the unique best alternative. The results of the 3E optimization and decision making analyses confirm the non-viability of the reference site for grid extension against other off-grid systems. Also, the 100 % hybrid renewable mini-grid system is nominated as the most sustainable design, and it yielded optimal capacities of 196 kW, 72 kW, 587 kW h, and 75 kW for photovoltaic, wind turbine, converter, and battery. The system has total life-cycle and energy costs of 751,597$ and 0.2374$/kWh, respectively, with a zero-emission value and maximum social benefits equals 0.6089 jobs/year. Meanwhile, the sensitivity analysis elucidates that the load growth and battery cost have a high impact on investment decisions rather than solar irradiance and wind speed. [ABSTRACT FROM AUTHOR]