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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 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]

The presence of renewable energy sources in hybrid renewable energy systems is considered a significant challenge since the generation mainly depends on meteorological conditions. Hence, employing a robust and flexible energy storage system is, therefore, a crucial solution in such circumstances. This paper investigates the performance evaluation of both batteries and superconducting magnetic energy storage (SMES) systems integrated with hybrid solar-wind DC-bus microgrid. The study focuses on enhancing the system stability using both storage technologies during normal and extreme renewables instabilities like wind gusts and shadows, and sudden load variations. Moreover, the load voltage/frequency were preserved constant during the distinct instabilities using the inverter control system. Productive findings showed the superior performance of utilizing the SMES over the batteries and its potential to enhance the system power-quality. [ABSTRACT FROM AUTHOR]

• An approach for modelling, simulation, and optimization of coastal MGs was developed. • Different DSM scenarios were implemented, evaluated, and compared. • Combined load shifting and load shaving techniques with hybrid MG attained the highest cost savings. • 100% renewable-based MG offered more sustainable design. • Sensitivity analysis proves the reliability and generalizability of the proposed approach. In the realm of sustainable power systems, the pivotal role of demand-side management (DSM) in Microgrids (MGs) design and planning is increasingly recognized. This study accentuates the significance of DSM in improving operational efficiency, economic viability, and environmental sustainability of MGs, focusing on a remote community in the Gulf Al-Aqaba, Sinai Peninsula, Egypt. An innovative four-level approach is proposed for the techno-enviro-economic modelling, simulation, and optimization-based DSM of MGs, addressing the challenges posed by renewable energy integration and fluctuating electricity demands. The research explores three demand scenarios: a base load without DSM (SC-1), load shifting-based DSM (SC-2), and a combined load shifting/peak shaving DSM (SC-3), to demonstrate the adaptability and robustness of MGs under different conditions. The findings reveal significant improvements in MG performance, with peak load reduction from 73.66 kW in SC-1 to 50.82 kW in SC-2 and 44.82 kW in SC-3, highlighting the effectiveness of the applied DSM strategies. These strategies also yield economic benefits, evident in an 8% and 23% decrease in the total life cycle cost for hybrid and 100% renewable MG configurations under SC-2 and SC-3, respectively, compared to SC-1. Particularly noteworthy is the reduction in required capacities of key MG components in the hybrid MG scenario under SC-3, with reductions of 10% for solar photovoltaic, 33% for microturbine generator, and 40% for battery energy storage, implying cost savings and a more efficient MG setup. Additionally, the environmental impact is profound, with an 80.3% decrease in emissions for the hybrid MG setup under SC-3 compared to a standalone 50 kW MTG system under SC-1. This outcome highlights the potential of DSM in contributing to environmental sustainability, particularly in MG configurations involving renewable energy sources. In conclusion, the study provides comprehensive insights into the synergy between DSM and MG optimization, underscoring its essential role in addressing climate change and transitioning to sustainable energy systems. [ABSTRACT FROM AUTHOR]

• A multi-objective optimization model for the optimal design of HMGESs is proposed. • The optimization model includes energy, economic and environmental aspects in the assessment. • SPV/WDG/DslG/Battery is the most economic, sustainable, and ecologically favorable option. • A power management strategy is applied efficiently on the optimized system to safeguard system power quality. Currently, the global gives a unique awareness of sustainable development by exploiting renewables to provide the people with affordable and clean energy and preserve the climate. This paper proposes a methodical and explicit framework of four phases, to design an autonomous hybrid renewable energy system in a community area in Egypt: preliminarily assessment, design optimization analysis, findings evaluation, and power-quality assessment. In the first three phases which performed by HOMER Pro® software, five hybridization scenarios are evaluated and compared regarding their life-cycle cost, carbon outflows, and reliability to distinguish the extraordinary scenario to supply the addressed community area. Contrary to the majority of studies that suffice only the first three phases, the fourth phase is proposed to perform a power-quality valuation based on a power management strategy (PMS). The results reveal that the optimal configuration consists of a photovoltaic generator, wind-driven generator, diesel-genset, battery-bank, and a power converter with the minimum net present cost of 351,223 $ and energy cost of 0.2262 $/kWh among all configurations. The optimal system has a negligible capacity shortage of 0.0955% and produces the least amount of emitted gases by 50.43 tones/year due to the high renewable fraction (57%). Moreover, the optimal proposed system can recover the invested money after only 3.4 years. The proposed PMS profitably harmonized the system's energy exchange, kept sufficient reserve energy at all times, and maintained the system stability under various meteorological and load disturbances. This can be verified from the superior stabilization of the dc-bus, load voltage and frequency during the examined disturbances. [ABSTRACT FROM AUTHOR]

• Model for the design and control of an off-grid 100% renewable system is proposed. • Nine alternatives of solar/wind/different storages are modelled and optimized. • Evaluation criteria are cost, emission, and load voltage/frequency constancy. • Solar/wind/lead-acid battery shows the most economic and reliable alternative. • Lead-acid battery/supercapacitor is more efficient than battery only. The continuous rise of global electricity demand and significant dependency on fossil fuel-based centralised power plants are the main indicators of increasing greenhouse gas emissions, thus negatively affecting climate change and human health and increasing the earth temperatures. This alarming situation has demanded the transition to 100 % renewable energy to decarbonise energy use. However, the fluctuating weather resources, and high investment cost are the major challenges with renewable energy implementation. In this context, the combined integration of multiple sources with energy storage in a so-called hybrid renewable energy system was developed as a durable remedy for the previous issues. This paper proposes a joint and conceptual approach for techno-economic design and dynamic rule-based power control of an off-grid solar/wind hybrid renewable energy system integrated with a hybrid energy storage system that comprises a lithium-ion battery, lead-acid battery, and a supercapacitor. Such concurrent integration of 100 % renewable energy systems and hybrid energy storage systems is lacking in the existing literature. First, with the aid of HOMER software, the feasibility and optimisation analysis of nine different configurations was performed in 1 min resolution to find the optimal component sizes. Second, MATLAB/Simulink models were assembled for the winning design based on a dynamic rule-based strategy to investigate and analyse the system's dynamic response, power equilibrium, DC-bus voltage supervision and load voltage/frequency control against instantaneous and dynamic changes in the load or renewable energy resources. The proposed approach was promoted and validated on an actual case study for isolated residential community electrification in Saudi Arabia, in which a multi-tier framework was adopted to accurately simulate the stochastic energy consumption of the community's households. From the design results, the hybrid renewable energy system, which integrates solar, wind, lead-acid batteries, and converter with optimal capacities of 55 kW, 18 kW, 325 kWh and 42 kW converter, respectively, is the most cost-effective alternative with the minimum net present and energy costs of $232,423.3 and $0.3458/kWh, respectively. The system has the least unmet load with 13.5 kWh/years (0.02 %), thus ensuring maximum reliability and customer satisfaction. Meanwhile, the developed control strategy efficiently improved the dynamic response, the DC-bus voltage stability, and the load voltage/frequency during different climatological and load interruptions. Further, the use of lead-acid batteries and supercapacitors has effectively diminished the maximum overshoot of the DC-bus and load voltages by 50 % during all disturbances. In addition, the integration of supercapacitors proficiently saved 2.3–6 kW during wind speed change and 2–9 kW during simultaneous changes in the radiation and load. Overall, the presented method, together with the reported results, provides an improved understanding and highlights the extent to which the successful integration of hybrid renewable energy system and hybrid energy storage system can be used to develop reliable and sustainable energy access for off-grid areas. [ABSTRACT FROM AUTHOR]