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Green hydrogen, a crucial component for producing renewable fuels, is particularly needed in sectors that are challenging to electrify directly. This research focuses on green hydrogen production in a grid-connected hybrid renewable energy plant, which requires strategic planning to meet long-term hydrogen purchase agreements while minimising costs and emissions. Unlike previous studies that relied on full foresight of renewable energy availability, electricity price, and CO 2 intensity in the electricity grid, this research introduces a novel long-term planner. This planner utilises historical data and short-term forecasts to plan daily hydrogen production, addressing the impracticality of the full foresight assumption which often leads to underestimations of both cost and CO 2 emissions. The long-term planner co-minimises cost and CO 2 emissions, determining the total hydrogen production for the upcoming day based on the remaining hydrogen production and the time remaining until the end of the delivery period, which can range from a week to a year. This approach provides operational flexibility, enabling reductions in cost and CO 2 emissions. The findings reveal that significant reductions in CO 2 emissions can be achieved with relatively small increases in the levelised cost. In daily operation, the levelised cost of hydrogen is marginally higher than that of the full foresight; the CO 2 emissions can be up to 60% higher. Despite a significant portion of the produced hydrogen not meeting the criteria for green hydrogen designation under current rules, CO 2 emissions are lower than those from existing alternative hydrogen production methods. These results underscore the importance of balancing cost considerations with environmental impacts in operational decision-making. The study suggests that improvements to current rules regarding the green labelling of hydrogen could involve implementing transparent accounting based on hourly CO 2 emissions and reducing the specific CO 2 emission threshold for green hydrogen production. This research contributes to the field by demonstrating a practical approach to hydrogen production planning and highlighting potential areas for policy improvement. • Historical and short-term forecast data are utilised to plan for long-term hydrogen targets. • Significant CO2 emission reductions can be achieved with a relatively small increase in cost. • Calculation of CO2 emissions based on full foresight can be significantly underestimated. [ABSTRACT FROM AUTHOR]

The potential for grid-connected solar photovoltaic (PV) systems to provide sustainable energy solutions across diverse climatic zones in Saudi Arabia was analyzed through a detailed feasibility study focusing on Dhahran and Bisha, representing different climatic conditions. In Dhahran, the power capacity for the six assessed PV technologies - Gintech, Jinko Solar, Apain Solar, Canadian Solar, Green Power, and Suntech-ranged from 11,970 kW to 12,012 kW, with the number of panels varying from 35,200 to 46,200. The solar collector area spanned from 61,242 m² to 88,715 m², and the electricity exported to the grid was consistent at approximately 18.770 MWh to 18,839 MWh. Initial costs were between USD 7,100,180 and USD 7,135,128, while revenue from exported electricity ranged from USD 912,378 to USD 915,079 with GHG emission reductions substantial at 9700 to 9736 tCO2. In Bisha, power capacities ranged between 9711 kW and 9800 kW, with panel counts from 28,600 to 37,750, and solar collector areas varying from 49.774 m² to 71,721 m². The electricity exported to the grid ranged from 18,780 MWh to 18,952 MWh. Initial costs were lower, between USD 5,768,334 and USD 5,821,200 and the revenue from exported electricity ranged from USD 912,686 to USD 921,051 with GHG emission reductions between 9705 and 9794 tCO2. These findings highlight the economic and environmental benefits of deploying grid-connected solar PV systems across different regions in Saudi Arabia, demonstrating significant potential for energy cost savings and substantial reductions in carbon emissions. [ABSTRACT FROM AUTHOR]

Depending on the PV power, load power, and battery status, the system may operate in different modes. The control loop may have to switch between operating modes. In practice, it is difficult to implement control loop switching because the transition and dynamic process are difficult to control. As a result, this paper presents a generalized mode control method that avoids loop switching across modes. First, system structure and topology are introduced. The operating conditions for both grid-connected and off-grid modes are then divided into six sub-cases. Furthermore, the control architecture, control loop, and reference transition for various scenarios are described. Finally, an experimental platform is built, and the results are presented to verify the proposed method. [ABSTRACT FROM AUTHOR]

The potential for grid-connected solar photovoltaic (PV) systems to provide sustainable energy solutions across diverse climatic zones in Saudi Arabia was analyzed through a detailed feasibility study focusing on Dhahran and Bisha, representing different climatic conditions. In Dhahran, the power capacity for the six assessed PV technologies—Gintech, Jinko Solar, Apain Solar, Canadian Solar, Green Power, and Suntech—ranged from 11,970 kW to 12,012 kW, with the number of panels varying from 35,200 to 46,200. The solar collector area spanned from 61,242 m² to 88,715 m², and the electricity exported to the grid was consistent at approximately 18,770 MWh to 18,839 MWh. Initial costs were between USD 7,100,180 and USD 7,135,128, while revenue from exported electricity ranged from USD 912,378 to USD 915.079 with GHG emission reductions substantial at 9,700 to 9,736 tCO2. In Bisha, power capacities ranged between 9,711 kW and 9,800 kW, with panel counts from 28,600 to 37,750, and solar collector areas varying from 49,774 m² to 71,721 m². The electricity exported to the grid ranged from 18,780 MWh to 18,952 MWh. Initial costs were lower, between USD 5,768,334 and USD 5,821,200 and the revenue from exported electricity ranged from USD 912,686 to USD 921,051 with GHG emission reductions between 9,705 and 9,794 tCO2. These findings highlight the economic and environmental benefits of deploying grid-connected solar PV systems across different regions in Saudi Arabia, demonstrating significant potential for energy cost savings and substantial reductions in carbon emissions.

Abstract Cameroon is currently grappling with a significant energy crisis, which is adversely affecting its economy due to cost, reliability, and availability constraints within the power infrastructure. While electrochemical storage presents a potential remedy, its implementation faces hurdles like high costs and technical limitations. Conversely, generator-based systems, although a viable alternative, bring their own set of issues such as noise pollution and demanding maintenance requirements. This paper meticulously assesses a novel hybrid energy system specifically engineered to meet the diverse energy needs of Douala, Cameroon. By employing advanced simulation techniques, especially the Hybrid Optimization Model for Electric Renewable (HOMER) Pro program, the study carefully examines the intricacies of load demands across distinct consumer categories while accommodating varied pricing models. The paper offers a detailed analysis of the proposed grid-connected PV/Diesel/Generator system, aiming to gauge its performance, economic feasibility, and reliability in ensuring uninterrupted energy supply. Notably, the study unveils significant potential for cost reduction per kilowatt-hour, indicating promising updated rates of $0.07/kW, $0.08/kW, and $0.06/kW for low, medium, and high usage groups, respectively. Furthermore, the research underscores the importance of overcoming operational challenges and constraints such as temperature fluctuations, equipment costs, and regulatory compliance. It also acknowledges the impact of operational nuances like maintenance and grid integration on system efficiency. As the world progresses towards renewable energy adoption and hybrid systems, this investigation lays a strong foundation for future advancements in renewable energy integration and energy management strategies. It strives to create a sustainable energy ecosystem in Cameroon and beyond, where hybrid energy systems play a pivotal role in mitigating power deficiencies and supporting sustainable development.

Abstract Economic development relies on access to electrical energy, which is crucial for society’s growth. However, power shortages are challenging due to non-renewable energy depletion, unregulated use, and a lack of new energy sources. Ethiopia’s Debre Markos distribution network experiences over 800 h of power outages annually, causing financial losses and resource waste on diesel generators (DGs) for backup use. To tackle these concerns, the present study suggests a hybrid power generation system, which combines solar and biogas resources, and integrates Superconducting Magnetic Energy Storage (SMES) and Pumped Hydro Energy Storage (PHES) technologies into the system. The study also thoroughly analyzes the current and anticipated demand connected to the distribution network using a backward/forward sweep load flow analysis method. The results indicate that the total power loss has reached its absolute maximum, and the voltage profiles of the networks have dropped below the minimal numerical values recommended by the Institute of Electrical and Electronics Engineers (IEEE) standards (i.e., 0.95–1.025 p.u.). After reviewing the current distribution network’s operation, additional steps were taken to improve its effectiveness, using metaheuristic optimization techniques to account for various objective functions and constraints. In the results section, it is demonstrated that the whale optimization algorithm (WOA) outperforms other metaheuristic optimization techniques across three important objective functions: financial, reliability, and greenhouse gas (GHG) emissions. This comparison is based on the capability of the natural selection whale optimization algorithm (NSWOA) to achieve the best possible values for four significant metrics: Cost of Energy (COE), Net Present Cost (NPC), Loss of Power Supply Probability (LPSP), and GHG Emissions. The NSWOA achieved optimal values for these metrics, namely 0.0812 €/kWh, 3.0017 × 106 €, 0.00875, and 7.3679 × 106 kg reduced, respectively. This is attributable to their thorough economic, reliability, and environmental evaluation. Finally, the forward/backward sweep load flow analysis employed during the proposed system’s integration significantly reduced the impact of new energy resources on the distribution network. This was evident in the reduction of total power losses from 470.78 to 18.54 kW and voltage deviation from 6.95 to 0.35 p.u., as well as the voltage profile of the distribution system being swung between 1 and 1.0234 p.u., which now comply with the standards set by the IEEE. Besides, a comparison of the cost and GHG emission efficiency of the proposed hybrid system with existing (grid + DGs) and alternative (only DGs) scenarios was done. The findings showed that, among the scenarios examined, the proposed system is the most economical and produces the least amount of GHG emissions.

Microhydraulic turbines offer a promising solution for decentralized energy production, suitable for both grid-connected and standalone applications, due to their compactness and high efficiency. This paper introduces a control approach for such systems employing microhydraulic turbines as distributed generators (DGs), utilizing six-phase induction generators for electricity production. This study emphasizes control strategies for both grid-connected and standalone modes utilizing proportional-integral (PI) controllers. An integrated energy storage system based on Li-Ion battery technology is also implemented to store the excess energy and compensate for production deficits to meet demand. The results obtained using MATLAB/Simulink demonstrate efficient and reliable power management among production sources, the grid and the local load, highlighting the unique contribution of employing a six-phase induction generator with the energy storage system. [ABSTRACT FROM AUTHOR]

This paper proposes a single-phase, transformer-less, seven-level inverter that utilizes eight switches, three capacitors, and two diodes to produce seven voltage levels with triple boosting ability. The availability of the common-ground point eliminates the leakage current in PV applications. The proposed Transformer-Less Triple-Boosting Seven-Level Inverter (TLTB7LI) has the ability to feed different types of loads from non-unity to unity power factors. The voltage balancing of capacitors takes place naturally without the need for auxiliary circuits and complicated control strategies. This paper investigates the appropriateness of the proposed TLTB7LI for grid-connected application. The Peak Current Controller (PCC) is employed to generate the switching pulses and regulate the active/reactive power transfer between the converter and the output, which guarantees the high quality of injected current to the output. Moreover, the operational principles, its control technique, as well as the design procedure of the key components of the proposed inverter have been presented. The superiority of the proposed inverter over existing counterparts has been verified through comparative analysis. The simulation and experimental analysis validated the proper operation of the proposed TLTB7LI. [ABSTRACT FROM AUTHOR]

In this research, the performance of vanadium redox flow batteries (VRFBs) in grid-connected energy storage systems centering on frequency and power sharing using voltage source inverters was evaluated. VRFBs are increasingly promising due to their scalability and long lifespan. We explore the impact of voltage source inverters on the frequency of the power supply when there is a change in load and power sharing between the grid and VRFB through MATLAB simulations. The test system demonstrates a storage system at an 11-kV substation and considers a load profile commencing from residential and commercial consumers. The outcome of this study reveals that VRFBs provide the required power to maintain load demand. Due to fast response time, VRFBs also regulate the frequency efficiently during the change in load demand and maintaining current total harmonic distortions (THDs). This research confirms the design and operation of VRFB-based energy storage systems, contributing to resilient grid infrastructure and reliable power distribution systems. [ABSTRACT FROM AUTHOR]

Economic development relies on access to electrical energy, which is crucial for society's growth. However, power shortages are challenging due to non-renewable energy depletion, unregulated use, and a lack of new energy sources. Ethiopia's Debre Markos distribution network experiences over 800 h of power outages annually, causing financial losses and resource waste on diesel generators (DGs) for backup use. To tackle these concerns, the present study suggests a hybrid power generation system, which combines solar and biogas resources, and integrates Superconducting Magnetic Energy Storage (SMES) and Pumped Hydro Energy Storage (PHES) technologies into the system. The study also thoroughly analyzes the current and anticipated demand connected to the distribution network using a backward/forward sweep load flow analysis method. The results indicate that the total power loss has reached its absolute maximum, and the voltage profiles of the networks have dropped below the minimal numerical values recommended by the Institute of Electrical and Electronics Engineers (IEEE) standards (i.e., 0.95–1.025 p.u.). After reviewing the current distribution network's operation, additional steps were taken to improve its effectiveness, using metaheuristic optimization techniques to account for various objective functions and constraints. In the results section, it is demonstrated that the whale optimization algorithm (WOA) outperforms other metaheuristic optimization techniques across three important objective functions: financial, reliability, and greenhouse gas (GHG) emissions. This comparison is based on the capability of the natural selection whale optimization algorithm (NSWOA) to achieve the best possible values for four significant metrics: Cost of Energy (COE), Net Present Cost (NPC), Loss of Power Supply Probability (LPSP), and GHG Emissions. The NSWOA achieved optimal values for these metrics, namely 0.0812 €/kWh, 3.0017 × 106 €, 0.00875, and 7.3679 × 106 kg reduced, respectively. This is attributable to their thorough economic, reliability, and environmental evaluation. Finally, the forward/backward sweep load flow analysis employed during the proposed system's integration significantly reduced the impact of new energy resources on the distribution network. This was evident in the reduction of total power losses from 470.78 to 18.54 kW and voltage deviation from 6.95 to 0.35 p.u., as well as the voltage profile of the distribution system being swung between 1 and 1.0234 p.u., which now comply with the standards set by the IEEE. Besides, a comparison of the cost and GHG emission efficiency of the proposed hybrid system with existing (grid + DGs) and alternative (only DGs) scenarios was done. The findings showed that, among the scenarios examined, the proposed system is the most economical and produces the least amount of GHG emissions. [ABSTRACT FROM AUTHOR]

Depending on the PV power, load power, and battery status, the system may operate in different modes. The control loop may have to switch between operating modes. In practice, it is difficult to implement control loop switching because the transition and dynamic process are difficult to control. As a result, this paper presents a generalized mode control method that avoids loop switching across modes. First, system structure and topology are introduced. The operating conditions for both grid-connected and off-grid modes are then divided into six sub-cases. Furthermore, the control architecture, control loop, and reference transition for various scenarios are described. Finally, an experimental platform is built, and the results are presented to verify the proposed method.

This study comprehensively analyzes the operational performance and economic feasibility of a 5MW grid-connected photovoltaic in Sudan over a two-year monitoring period. Leveraging the capabilities of PVSyst software, the actual plant performance was rigorously compared to simulation predictions. Results revealed a significant disparity between observed and simulated energy generation, prompting the exploration of potential areas for enhancement. Seasonal fluctuations in the performance ratio were evident, with peak values during some seasons, albeit not consistently aligning with simulation projections. Despite these challenges, the Plant made a notable impact by reducing CO2 emissions, highlighting the environmental benefits of solar energy. Financial analysis unveiled discrepancies between actual and simulated savings, underscoring the need for optimization and efficiency improvements. The equity payback period, influenced by electricity pricing policies, was estimated at 15 years, emphasizing its role in assessing project economics. The region's high radiation intensity and humidity levels emerged as significant factors affecting plant performance. Addressing these challenges is crucial for maximizing the PV plant's operational efficiency and viability. Our Recommendations include thoroughly examining control system functions during commissioning and improving operational accuracy.

To foster resilient energy transition systems, the deployment of renewable energy sources is potentially helpful in the acceleration towards sustainable, reliable, and diversified solutions. In this feasibility study, aims to pursuit the best optimal solution for renewable energy resources, integrated into the local university's energy mix, to meet the electrical load demand of 8500 kWhr/day and a peak load of 815 kW. A model of a hybrid grid-connected renewable energy (PV/Biomass/Hydel/Diesel generator/Grid) system was implemented in HOMER software, to obtain the most efficient and cost-effective hybrid energy generation. The outcomes of the simulation seem more viable based on sensitivity analysis, as the cost of energy (COE) for an energy system with a hybrid combination is 0.13 $/kWh, meanwhile energy price with the grid system is 0.18 $/kWh. According to the HOMER analysis, a hybrid grid-connected PV/biomass/hydro system demonstrates both technological feasibility and economic viability, meanwhile it will also save 1575 tons of CO2 per year. Therefore, this proposed hybrid energy system, a step towards sustainable development, can be applied at institutional levels, especially in developing countries.

Hydrogen energy storage and grid integration are emerging as key technologies for efficient energy generation and decarbonization, addressing the unpredictability of renewable sources like wind and solar. Hydrogen serves as a flexible energy carrier, enabling storage and conversion back to energy, and supporting various applications. Since there is a lack of bibliometric investigation in the grid-connected hydrogen energy storage system, this review conducted the bibliometric analysis and analyzed the role of hydrogen in enhancing grid-connected systems' sustainability and flexibility, based on data from the Scopus database. The principal search terms that have been used to identify the publications are "Hydrogen AND Storage AND ("Grid-connected" OR "On-grid" OR "Grid-tied" OR "Integrated grid" OR "Grid integration")" and several keywords have also been utilized in the filter including "Hydrogen Storage", "Hydrogen", "Hydrogen Production" and "Grid-connected". The chosen documents type is only comprised of 'Article' and 'Review'. By conducting an analysis of publication trends, citation patterns, co-authorship, and keyword usage, significant and informative observations regarding the development of grid-connected hydrogen storage system research from 2013 to 2023 (up until November) were unveiled. Notably, 86.55% of the articles focused on simulation study, while the rest are focusing in experimental work, reviews, and technical overview of integrated-grid hydrogen storage system. China is establishing itself as prominent participant, while International Journal of Hydrogen Energy is recognized as a notable medium for distributing research on the integrated-grid hydrogen storage system. Compressed hydrogen tank emerges as a prominent type of storage because of its less energy requirement to increase the density of hydrogen that allow more efficient transportation for hydrogen. The review also underlines numerous factors, issues, challenges, and difficulties that next-generation hydrogen energy storage production should overcome with regards to system sustainability. • Comprehensive bibliometric analysis of grid-integrated hydrogen storage in investigated. • The most prominent types of hydrogen storage technologies are examined. • Numerous factors, issues, and challenges on hydrogen storage grid is reviewd. • The control strategies are significantly boost the efficiency of hydrogen production. • A statistical analysis of hydrogen storage integrated grid sustainability is investigated. [ABSTRACT FROM AUTHOR]

This study proposes an unbalanced current compensation method based on a four-leg inverter using an artificial neural network (ANN) under unbalanced load conditions. Distribution systems exhibit rapid load variations, and conventional filter-based control methods suffer from the drawback of requiring an extended time period to reach a steady state. To address this problem, an ANN is applied to calculate the unbalanced current reference and enhance dynamic performance. Additionally, because of the periodic incorrect output inherent in the ANN, applying it to a proportional–integral controller would result in an error being directly reflected in the current reference. In the aforementioned problem, an ANN is applied to the dq0 coordinate system current controller to compensate for the periodic incorrect output in the current reference calculation. The proposed ANN-based unbalanced current compensation method is validated through PSIM simulations and experiments. [ABSTRACT FROM AUTHOR]

Electric vehicle charging stations (EVCSs) and renewable energy sources (RESs) have been widely integrated into distribution systems. Electric vehicles (EVs) offer advantages for distribution systems, such as increasing reliability and efficiency, reducing pollutant emissions, and decreasing dependence on non-endogenous resources. In addition, vehicle-to-grid (V2G) technology has made EVs a potential form of portable energy storage, alleviating the random fluctuation of renewable energy power. This paper simulates the optimal design of a photovoltaic/wind/battery hybrid energy system as a power system combined with an electric vehicle charging station (EVCS) using V2G technology in a grid-connected system. The rule-based energy management strategy (RB-EMS) is used to control and observe the proposed system power flow. A multi-objective improved arithmetic optimization algorithm (MOIAOA) concept is proposed to analyze the optimal sizing of the proposed system components by calculating the optimal values of the three conflicting objectives: grid contribution factor (GCF), levelled cost of electricity (LCOE), and energy sold to the grid ( E S O L D ). This research uses a collection of meteorological data such as solar radiation, temperature, and wind speed captured every ten minutes for one year for a government building in Al-Najaf Governorate, Iraq. The results indicated that the optimal configuration of the proposed system using the MOIAOA method consists of eight photovoltaic modules, two wind turbines, and thirty-three storage batteries, while the fitness value is equal to 0.1522, the LCOE is equal to 2.66 × 10 − 2 USD/kWh, the GCF is equal to 7.34 × 10 − 5 kWh, and the E S O L D is equal to 0.8409 kWh. The integration of RESs with an EV-based grid-connected system is considered the best choice for real applications, owing to their remarkable performance and techno-economic development. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Xinjiang University (Natural Science Edition) is the property of Xinjiang University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper solves the control problem to track the maximum power in gridconnected PV systems to catch up with the changes and meet the energy demand, given the irregular and arbitrary nature of the solar source. Our work addresses the following objectives: i) extracting the maximum available power under partial shading, ii) and having a unit power factor. To achieve the above objectives, we have integrated two control components. The first one is dedicated to the extraction of the maximum power point (MPPT) particle swarming algorithm (PSO) with a backstepping controller, by shaking on the DC/DC converter duty cycle to increase the robustness and stability of the system. The backstepping control of the three-phase voltage source inverter is the second part. To verify the effectiveness of the introduced system, modelling and simulation are verified in MATLAB/Simulink. [ABSTRACT FROM AUTHOR]

Transformerless grid-connected inverters for photovoltaic (PV) applications provide several advantages such as reduced cost and volume as well as an increased efficiency. However, the removal of the transformer gives rise to several problems related to leakage currents and electromagnetic interferences (EMI). This paper presents different chaotic unipolar sine-pulse width modulation (C-USPWM) techniques for a transformerless grid-connected PV inverter based on parameter selection. The main objective behind this proposed chaotic modulation technique is to reduce the conducted EMI without worsening the power quality and the common-mode voltage (CMV). The method is validated through numerical simulations and experimental tests carried out on laboratory prototype of an optimized H5 inverter (oH5). The obtained results showed its superiority to the conventional unipolar sine-pulse width modulation (USPWM). We showed also that the appropriate parameter selection of the C-UPSWM could advantageously combine an improved EMI performance and an efficient control, making it possible to deliver a significant reduction of the peaks' amplitudes in the frequency spectrum of the common-mode (CM) voltage. [ABSTRACT FROM AUTHOR]

Large grid-connected photovoltaic (PV) plants are increasingly being installed around the world, including in harsh desert climates. Evaluating their performance can help improve the design and operation of PV systems. This study performed an energy and exergy analysis of a 20-MW grid-connected PV plant under desert climatic conditions in southern Algeria over a period of 1 year. The PV plant was divided into two 10-MW subsystems. Energy analysis was performed using actual irradiation, power output, wind speed and ambient temperature data. The annual average energy efficiency of the plant and subsystems was 10.82%, 10.95% and 10.69%, respectively. Solar radiation had the most significant impact (80% determination coefficient) on thermal exergy loss. The exergy efficiency of the plant was lower than the literature values, likely due to the harsh desert conditions. The comprehensive energy and exergy analysis provides insights into the performance of large-scale PV plants in desert climates. The results can help guide the system design and operation improvements for such conditions. Regular cleaning and cooling could improve performance. [ABSTRACT FROM AUTHOR]

Renewable energy systems, such as solar power, are becoming increasingly important worldwide due to the limited supply of non-renewable energy sources. Solar power stands out as a practical choice for electricity generation because it's simple to set up and costs less than other renewable options. Solar-based on-grid or grid-tied systems are more effective compared to other PV grid systems due to their more reasonable installation system, favorable maintenance, and less complex system. This study was designed with a solar-based grid-tied system. This study evaluates the performance and economic viability of a 15 MW on-grid photovoltaic (PV) system in Bakalia Char, Chittagong, Bangladesh, and will propose this study for the Bangladesh Power Development Board (BPDB). Developing a clean energy system in Bangladesh is the main purpose of this study. This system performed efficiently, with an 84.03 % performance ratio, produced energy of 21,510.186 MWh/year and proved economically attractive with a 4.5-year payback period, a competitive electricity cost of 0.024 USD/kWh, and a 389 % return on investment(ROI%). Using software like PVsyst and SketchUp ensures precise system design and optimal module placement. Also, use a better PV panel system whose efficiency is higher than that of another PV panel system designed for a similar project. This system boosts local electricity production and aligns with sustainable energy goals. Its success is a valuable model for future solar projects in similar regions facing energy challenges. The system also shows significant environmental benefits, with a projected reduction of approximately 252,168.5 tons of CO2 emissions over its operational lifespan.

This study presents a comprehensive bibliometric analysis of grid-connected microgrid (MG) scheduling controller techniques. An extensive search was done in the Scopus database using preset parameters to extract articles relating to the MG scheduling controller. The selection of the most cited paper involved careful keyword filtering on grid-connected MG scheduling controllers over the period from 2013 to 2024. Within the timeframe, a total of 115 top-cited articles were extracted, focusing on the scheduling controller algorithms applied to the grid-connected MG system. These highly cited articles originated from a diverse source, encompassing 49 distinct journals, spanning 28 different regions, and representing the publications of 7 distinct publishers. This paper seeks to identify and analyze the highly referenced published articles in the relevant area to yield an in-depth analysis of advanced controllers and optimization strategies in MG energy management systems. The key challenges such as power electronic interface, quality, controller, safety and optimization were also highlighted to provide the clearest insight on the recent MG development. Valuable recommendations for future research directions are also provided, aimed at promoting the sustainable growth of MGs. A substantial total of 63.56% articles were published based on simulation while 18.6%, 13.95% and 3.87% of total articles were published on the experimental setup, critical analysis and review-based study. Therefore, it can be inferred that ongoing research and development efforts continually seek to improve the sustainability of MG systems within the electric power sector. The bibliometric analysis was employed to identify pivotal research publications concerning grid-connected MG scheduling controller technique. This analysis aimed to delineate the multidisciplinary nature, illustrate trends, and outline areas warranting further research in the field. Thus, to ensure an effective, economical, reliable, and sustainable power supply, this analysis will broaden the scope and offer context for the development of MG scheduling controller integrated grid systems.

In recent years, there has been a proliferation of studies focusing on sustainable energy sources aimed at delivering reliable power with reduced greenhouse gas emissions. Among these endeavors, electrification of urban areas through incorporation of renewable energy sources (RESs) stands out as a pivotal application of RES. Increasingly, the integration of RESs like PV and wind into the power grid is being pursued as an alternative to traditional centralized power stations, offering a means to ensure continuous power supply during peak demand periods while simultaneously managing unit costs, thereby providing a systematic and readily accessible power supply to consumers. This paper presents a comprehensive examination of hybrid wind and PV with focus on achieving consistent DC bus-bar voltage through integration with microcontroller system via buck-boost converter. Additionally, hybrid system’s output voltage is tailored to accommodate necessary battery connections. However, given influence of environmental variables like fluctuations in solar irradiation and wind velocity on power output of PV and wind seamless integration of these sources becomes paramount. To address this challenge MATLAB model is developed to simulate grid integration of hybrid wind and PV, enabling a detailed analysis of integrated grid’s performance. Simulation results are then proposed with those obtained from conventional fossil fuel-based power generation methods. In this research underscores importance of integrating RES into existing power grids and highlights efficacy of hybrid wind and PV in meeting this objective. Findings presented herein contribute to advancing discourse on sustainable energy solutions, offering valuable insights for policymakers, industry stakeholders, and researchers.

This paper proposes a new control policy for optimal control of the 3-phase system of PEMFC connected to the grid. This also includes a 3-phase high step-up Interleaved Boost Converter (IBC) to amplify the PEMFC outputted voltage. To control the PEMFC system, Maximum Power Point Tracking (MPPT) based on Rigdelet Neural Networks (RNN) has been utilized, and to improve this controller, an improved version of the Satin Bowerbird Optimization (ISBO) algorithm has been utilized. The main advantage of the proposed improved version is modifying the convergence weakness and fixing convergence in chaos theory. The method is then validated by performing it one time on a standalone PEMFC system and another time on a grid-connected PEMFC system. Simulation results indicate that based o the IBC converter, better results with lower current ripples can be achieved. Also, the method has the ability to feed to both active and reactive powers by keeping stable the sudden temperatures. Final results have been also put in comparison with two different latest techniques to indicate the technique proficiency.

Copyright of Journal of Engineering & Architectural Faculty of Eskisehir Osmangazi University / Eskişehir Osmangazi Üniversitesi Mühendislik ve Mimarlık Fakültesi Dergisi is the property of Eskisehir Osmangazi University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The design and optimization of power converters is a key factor in the growth and development of the power electronics field. However, the process of designing a power converter is not straightforward, and engineers often rely on experience and intuition, sometimes requiring time-consuming computer simulations. This paper presents a tool for the basic design of grid-connected AC–DC converters. The design tool takes specifications and operating conditions for two-level and three-level NPC converter topologies and derives a draft design. The tool calculates the input filter's electrical parameters, the converter's losses, the temperature rise of the power semiconductor devices, and the ripple current and voltage of the DC-link capacitor. In order to validate the proposed design tool, four AC–DC converters using SiC MOSFETs were designed. Based on the design results, simulation models and prototypes were fabricated to verify the performance and confirm that the proposed design tool can be used in the basic design process of converters. [ABSTRACT FROM AUTHOR]

This paper exhibits the performance of crystalline-based solar cells (polycrystalline and monocrystalline) as well as the comparative analysis of these solar cells following various types of orientation in the solar plant. Since the global energy demand is increasing rapidly, different sorts of renewable energy have been used in the last decades to meet this massive demand all over the world. From recent studies, solar has been considered the most promising among these renewable sources. To analyze the performance, the geographical site (Savar, Dhaka) was selected which has a latitude of 23.8538° and a longitude of 90.2534°. In this study, the most effective polycrystalline and monocrystalline solar cell has been founded which is 440 and 370 wp, respectively. Regarding this, a grid-connected PV system (12.3 Kwp) has been simulated which showed the performance ratio of the monocrystalline cell was 83.55%, which was better than the polycrystalline-based solar cell which was 79.6%. In terms of different kinds of orientations, monocrystalline at dual-axis tracking planes showed the highest value of energy injection to the grid was 25.8 MWh/year, while the least value has been founded in the fixed orientation plane which was 20.6 MWh/year. In this perspective, polycrystalline showed 23.9 and 19.5 MWh/year for dual-axis tracking and fixed orientation planes, respectively. Monocrystalline showed more energy injected into the grid compared to polycrystalline technologies for every orientation in the plant as well as the highest value of performance ratio. [ABSTRACT FROM AUTHOR]

This article presents an overview of the technical and financial feasibility analysis of integrating a photovoltaic (PV) source with the conventional power system to supply the auxiliary load at the Al Suwairah 33/11 kV primary substation (PSS) in Suhar, Sultanate of Oman. This study estimates the required electrical energy for the primary substation's auxiliary load. A method is implemented to utilize the available area in the primary substation for determining the solar photovoltaic system's capacity. PVSyst software is employed to determine the ideal system capacity. The proposed solar PV system's payback period and overall annual savings have been evaluated using a series of simulated analyses. The proposed PV can inject 172.5 MWh/year with an average performance ratio of 0.826. The economic evaluation by the photovoltaic system (PVSyst) considering the present auxiliary load at the Al Suwarah PSS has suggested a total payback period of 8.9 years which is quite feasible. The cost of power generated by the proposed system is 49.2% less than the cost of power supplied from the utility service provider. [ABSTRACT FROM AUTHOR]

This paper presents a methodology for the optimal sizing of a proposed photovoltaic (PV)-battery grid-connected system for fast charging station of electric vehicles (FCSEVs) in Cairo, Egypt. The key objectives of the formulated optimization problem are to minimize the total system cost and to guarantee the validity of the energy balance principle within the considered system. The paper also develops a novel energy management strategy, which is designed based on two widely adopted pricing strategies, for optimally managing the power flow within the considered system with the purpose of reaching the optimum sizes of the considered system components. In addition, the paper suggests a modification to the Snake optimization (SO) algorithm, which is used to solve the formulated optimization problem using MATLAB software. Moreover, a comparison is conducted among the proposed modified Snake optimization (MSO) algorithm and four other common meta-heuristic optimization algorithms to validate the viability of the suggested MSO algorithm in achieving the desired eventual aims of the sizing process. Furthermore, a techno-economic study is carried out to assess the economic viability of the proposed system for each of the two adopted pricing strategies over the project lifetime. The yielded results indicated that the developed energy management strategy is capable of managing the energy flow within the considered system effectively. Also, they demonstrated that the suggested MSO algorithm can yield the best optimal solutions for the formulated optimization problem for each of the two adopted pricing strategies compared to the other considered optimization algorithms.

Grid-connected photovoltaic (PV) system is often needed whenever utilities fail to provide consumers with a reliable, sufficient and quality power supply. It provides more effective utilization of power, however, there are technical requirements to ensure the safety of the PV installation and utility grid reliability. In solar systems there is often excessive use of components, resulting in high installation costs. Consequently, appropriate measures must be taken to develop a cost-effective grid-connected PV system. An optimally sized PV system incorporated into an existing unreliable grid-connected commercial load for Mount Olive food processing is presented in this paper. The study focused on providing a reliable electricity supply which is cost-effective and environment-friendly. The techno-economic analysis of grid-connected PV/Diesel/Battery Storage systems was carried out using HOMER Pro software. Results showed that Grid/PV/BSS are technically, economically and environmentally feasible with the cost of energy at 0.136$/kWh and net present cost at $254,469. Also, the excess electricity produced by this combination is 13,264kWh/year, which generates income for the company by selling excess generated energy back to the grid if net metering were to be implemented. Furthermore, the CO2 emissions for these combinations decreased to 10,081.6 kg/year as compared to the existing systems (Grid/Diesel Generator) with emissions of 124,480 kg/year. This is an additional advantage in that it improves the greenhouse effect. A sensitivity analysis was carried out on the variation of load change, grid power price and schedule outages for the optimal system.

This paper proposes a single-phase, transformer-less, seven-level inverter that utilizes eight switches, three capacitors, and two diodes to produce seven voltage levels with triple boosting ability. The availability of the common-ground point eliminates the leakage current in PV applications. The proposed Transformer-Less Triple-Boosting Seven-Level Inverter (TLTB7LI) has the ability to feed different types of loads from non-unity to unity power factors. The voltage balancing of capacitors takes place naturally without the need for auxiliary circuits and complicated control strategies. This paper investigates the appropriateness of the proposed TLTB7LI for grid-connected application. The Peak Current Controller (PCC) is employed to generate the switching pulses and regulate the active/reactive power transfer between the converter and the output, which guarantees the high quality of injected current to the output. Moreover, the operational principles, its control technique, as well as the design procedure of the key components of the proposed inverter have been presented. The superiority of the proposed inverter over existing counterparts has been verified through comparative analysis. The simulation and experimental analysis validated the proper operation of the proposed TLTB7LI.

In recent years, increasing the rate of green energy use in order to meet the increasing energy demand and combat global warming has become one of the important goals of the countries. For this reason, the integration of renewable energy sources as distributed generation has become increasingly popular. In this study, hybrid renewable energy systems were designed for the electrification of a 100-household area in the Sarayköy district of Denizli province, Turkey, and the Hybrid Optimization Model for Electric Renewables program was used to optimize the required component outputs to to achieve the best economic and environmental results. A total of six hybrid renewable energy system designs, three grid-connected and three stand-alone, were created with different combinations of components such as photovoltaic panel, wind turbine, diesel generator, battery energy storage system, and converter. The most economical design was the grid-connected system with only solar energy with a unit energy cost of 0.0362 $/kWh, while the most cost-effective was the stand-alone system containing solar energy, wind energy, and batteries with 1.61 $/kWh. In terms of the environment, on the contrary, off-grid systems emit less carbon dioxide, while on-grid systems emit more carbon dioxide. [ABSTRACT FROM AUTHOR]

Fuel cells are a newly developed source for generating electric energy. These cells produce electricity through a chemical reaction between oxygen and hydrogen, which releases electrons. In recent years, extensive research has been conducted in this field, leading to the emergence of high-power batteries. This study introduces a novel technique to enhance the power quality of grid-connected proton-exchange membrane (PEM) fuel cells. The proposed approach uses an inverter following a buck converter that reduces voltage. A modified pelican optimization (MPO) algorithm optimizes the controller firing. A comparison is made between the controller's performance, based on the recommended MPO algorithm and various other recent approaches, demonstrating the superior efficiency of the MPO algorithm. The study's findings indicate that the current–voltage relationship in proton-exchange membrane fuel cells (PEMFCs) follows a logarithmic pattern, but becomes linear in the presence of ohmic overvoltage. Furthermore, the PEMFC operates at an impressive efficiency of 60.43% when running at 8 A, and it can deliver a significant power output under specific operating conditions. The MPO algorithm surpasses other strategies in terms of efficiency and reduction in voltage deviation, highlighting its effectiveness in managing the voltage stability, and improving the overall performance. Even during a 0.2 sagging event, the MPO-based controller successfully maintains the fuel cell voltage near its rated value, showcasing the robustness of the optimized regulators. The suggested MPO algorithm also achieves a superior accuracy in maintaining the voltage stability across various operating conditions. [ABSTRACT FROM AUTHOR]

Grid-connected photovoltaic (PV) system is often needed whenever utilities fail to provide consumers with a reliable, sufficient and quality power supply. It provides more effective utilization of power, however, there are technical requirements to ensure the safety of the PV installation and utility grid reliability. In solar systems there is often excessive use of components, resulting in high installation costs. Consequently, appropriate measures must be taken to develop a cost-effective grid-connected PV system. An optimally sized PV system incorporated into an existing unreliable gridconnected commercial load for Mount Olive food processing is presented in this paper. The study focused on providing a reliable electricity supply which is cost-effective and environment-friendly. The techno-economic analysis of grid-connected PV/Diesel/Battery Storage systems was carried out using HOMER Pro software. Results showed that Grid/PV/BSS are technically, economically and environmentally feasible with the cost of energy at 0.136$/kWh and net present cost at $254,469. Also, the excess electricity produced by this combination is 13,264kWh/year, which generates income for the company by selling excess generated energy back to the grid if net metering were to be implemented. Furthermore, the CO2 emissions for these combinations decreased to 10,081.6 kg/year as compared to the existing systems (Grid/Diesel Generator) with emissions of 124,480 kg/year. This is an additional advantage in that it improves the greenhouse effect. A sensitivity analysis was carried out on the variation of load change, grid power price and schedule outages for the optimal system. [ABSTRACT FROM AUTHOR]

In this article, a novel switched‐capacitor multilevel inverter (SC‐MLI) for on‐grid and off‐grid applications with PV is presented. The nine‐level proposed SC‐MLI with simple architecture is produced gain of four times across the load voltage. Further, the proposed inverter needs only 10 power switches, a single dc source, three diodes, and three capacitors. For a suitable switching operation, phase disposition pulse width modulation (PD‐PWM) was developed. Furthermore, the capacitor inrush current, which is a major shortcoming of SC‐MLI, is mitigated in the proposed topology by employing a charging inductor. Furthermore, the proposed inverter is used as a single‐stage PV grid‐tied inverter. When inverter is used for PV applications, the proposed inverter provides minimum value of leakage current. In addition, to demonstrate the superior performance of the proposed switched capacitor MLI, a comparative analysis with an existing off‐grid and existing on‐grid SC‐MLIs is performed. A fully circuit has been simulated using Matlab/Simulink to test the effectiveness and feasibility of the proposed topology. The prototype of the hardware system is designed of a nine‐level proposed topology using the dSpace 1103 controller board to validate the results. [ABSTRACT FROM AUTHOR]

Access to cheap, clean energy has a significant impact on a country's ability to develop sustainably. Fossil fuels have a major impact on global warming and are currently becoming less and less profitable when used to generate power. In order to replace the diesel generators that are connected to the university of Debre Markos' electrical distribution network with hybrid renewable energy sources, this study presents optimization and techno-economic feasibility analyses of proposed hybrid renewable systems and their overall cost impact in stand-alone and grid-connected modes of operation. Metaheuristic optimization techniques such as enhanced whale optimization algorithm (EWOA), whale optimization algorithm (WOA), and African vultures' optimization algorithm (AVOA) are used for the optimal sizing of the hybrid renewable energy sources according to financial and reliability evaluation parameters. After developing a MATLAB program to size hybrid systems, the total current cost (TCC) was calculated using the aforementioned metaheuristic optimization techniques (i.e., EWOA, WOA, and AVOA). In the grid-connected mode of operation, the TCC was 4.507 × 106 EUR, 4.515 × 106 EUR, and 4.538 × 106 EUR, respectively, whereas in stand-alone mode, the TCC was 4.817 × 106 EUR, 4.868 × 106 EUR, and 4.885 × 106 EUR, respectively. In the grid-connected mode of operation, EWOA outcomes lowered the TCC by 0.18% using WOA and 0.69% using AVOA, and by 1.05% using WOA and 1.39% using AVOA in stand-alone operational mode. In addition, when compared with different financial evaluation parameters such as net present cost (NPC) (EUR), cost of energy (COE) (EUR/kWh), and levelized cost of energy (LCOE) (EUR/kWh), and reliability parameters such as expected energy not supplied (EENS), loss of power supply probability (LPSP), reliability index (IR), loss of load probability (LOLP), and loss of load expectation (LOLE), EWOA efficiently reduced the overall current cost while fulfilling the constraints imposed by the objective function. According to the result comparison, EWOA outperformed the competition in terms of total current costs with reliability improvements. [ABSTRACT FROM AUTHOR]

This study focuses on the evaluation of the economic viability of various scale wind farms and the assessment for the first time of the wind power potential of 22 locations distributed over Libya. The study utilizes monthly mean wind data collected from the NASA power dataset. The analysis includes determining and analyzing the mean wind speed, frequency distribution, and Weibull distribution scale and shape factors. The results showed that Darnah is the most promising location for insulation wind farms due to the high value of wind speed. Moreover, RETScreen software is used to estimate the energy output and conduct an economic feasibility analysis of the wind farm. Additionally, this paper establishes a relationship between the wake effect, airfoil losses, and the potential for greenhouse gas (GHG) mitigation and the performance of wind farms. The results indicate that wind projects are economically viable when the EWT-DW 52 with a capacity of 500 kW is used. The study findings show that the wake effect is a crucial consideration in wind farm design, and it can be minimized through strategic spacing and turbine design. Furthermore, the accumulation of dirt and debris on wind turbine blades can significantly reduce a wind farm's energy output, causing turbine inefficiency and decreasing the overall energy production. Additionally, the energy production cost from a wind farm is less than that of the electricity tariff and can result in a profitable wind energy project. [ABSTRACT FROM AUTHOR]

Virtual synchronous generator (VSG) can simulate synchronous generator turning and damping characteristics, which can further improve the penetration rate of renewable energy in the grid. However, the output impedance of virtual synchronous generator in medium and low voltage microgrids is dominated by resistance, which leads to the coupling of active/reactive power and affects the grid integration control effect, and the phase of VSG and grid voltage will be biased in the absence of a pre-synchronization link. For this purpose, a strategy of grid-connected control of VSG with virtual impedance is proposed. Firstly, the VSG mathematical model is established and virtual impedance is introduced into the VSG electrical portion to improve the grid-connected inverter output characteristics. Secondly, a secondary frequency and voltage regulation strategy to improve VSG control is proposed to restore the frequency and voltage of the VSG, and the SOGI phase-locked loop collects the grid voltage phase to complete the grid-connected pre-synchronization design. Finally, the effectiveness and correctness of the proposed strategy were verified by the simulation results based on MATLAB/ Simulink.

This study proposes an unbalanced current compensation method based on a four-leg inverter using an artificial neural network (ANN) under unbalanced load conditions. Distribution systems exhibit rapid load variations, and conventional filter-based control methods suffer from the drawback of requiring an extended time period to reach a steady state. To address this problem, an ANN is applied to calculate the unbalanced current reference and enhance dynamic performance. Additionally, because of the periodic incorrect output inherent in the ANN, applying it to a proportional–integral controller would result in an error being directly reflected in the current reference. In the aforementioned problem, an ANN is applied to the dq0 coordinate system current controller to compensate for the periodic incorrect output in the current reference calculation. The proposed ANN-based unbalanced current compensation method is validated through PSIM simulations and experiments.

Microgrids technologies are seen as a cost effective and reliable solution to handle numerous challenges, mainly related to climate change and power demand increase. This is mainly due to their potential for integrating available on-site renewable energy sources and their flexibility and scalability. The particularity of microgrids is related to their capacity to operate in synchronization with the main grid or in islanded mode to secure the power supply of nearby end-users after a grid failure thanks to storage solutions and an intelligent control system. The most critical operating case occurs when a sudden transition from grid-connected (GC) to stand-alone operation (SA) happens. During the transition, the system experiences abrupt changes that can result in a malfunction of the control system and a possible failure of the power system. The transition issue attracted considerable attention from researchers. Indeed, many research works are proposed to address this issue by proposing detection and transition techniques that ensure a smooth transition at the islanding time. Although there are several approaches to dealing with this issue, a categorization of the proposed methods in the literature and their differences is useful to assist engineers and researchers working on this topic. Thus, this study proposes a comprehensive review to summarize these approaches and point out their advantages and limitations. [ABSTRACT FROM AUTHOR]