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Amidst the evolving paradigms of the contemporary energy landscape, marked by the imperative of sustainability and efficiency, the integration of energy storage has emerged as a transformative strategy that seeks to recalibrate the dynamics of electricity distribution and consumption. However, there remains a pressing need to determine the most economically viable approach for deploying energy storage solutions in residential low-voltage (LV) feeders, especially in rural areas. In this context, this paper presents the results of an economic evaluation of energy storage solutions for a residential LV feeder in a rural town in Australia. Specifically, the study compares the financial viability of a front-of-the-meter (FTM) battery installed on the feeder with that of a fleet of behind-the-meter (BTM) batteries. The FTM battery, with a size of 100 kW/200 kWh, is assumed to be operated by the retailer but owned by the community, with any profits assigned to the community. In this scenario, we studied a battery operating under standard network tariffs and three different trial tariffs that distribution network service providers currently offer in Australia. On the other hand, the fleet of BTM batteries (3 kW, 3.3 kWh) are individually owned by households with solar installations, and their cumulative capacity matches that of the FTM battery. The comparison is based on key economic parameters, including network charges, retail margins, frequency control ancillary service (FCAS) revenues, wholesale energy costs, technology costs associated with community batteries, and net profit or loss for the community, as well as considerations of utility grid arbitrage and solar photovoltaic (PV) self-consumption. The study also assumes different grant levels to assess the impact of subsidies on the economic feasibility for both battery configurations. The findings indicate that, while both require some form of subsidy for profitability, the BTM batteries outperform the FTM battery in terms of economic viability and so would require lower grant support. The FTM battery case finds a need for grants ranging from 75% to 95% to break even, while the BTM fleet requires approximately 50% in grants to achieve a similar outcome. In conclusion, this study highlights the importance of grant support in making energy storage solutions economically feasible. In particular, it highlights how the less mature segment of FTM batteries will need higher support initially if it is to compete with BTM. The outcomes of this study inform decision-making processes for implementing energy storage solutions in similar communities, fostering sustainable and cost-effective energy systems. [ABSTRACT FROM AUTHOR]

As the proportion of renewable energy generation systems increases, traditional power generation facilities begin to face challenges, such as reduced output power and having the power turned off. The challenges are causing changes in the structure of the power system. Renewable energy sources, mainly wind and solar energy cannot provide stable inertia and frequency regulation capability. Ultimately, the power system's emergency response capability to face an N-1 is reduced, which leads to a reduction in system stability. Therefore, the application technology of the battery energy storage system is used to support the impact of changes in the new power system structure. This paper designed control technologies based on the WECC second-generation generic model, namely, dynamic regulation, steady regulation, and virtual inertia regulation. The models and control strategies are verified on Taiwan's 2025 power system target conditions, which consider the expected capacities for battery energy storage systems, and renewable energy sources with different load and N-1 fault levels. According to the simulation results, the capabilities of the RoCoF limitation, frequency nadir, frequency recovery, and system oscillation regulation are evaluated in the proposed strategies. Finally, the analysis results can help power operators make informed decisions when selecting and deploying battery energy storage systems. [ABSTRACT FROM AUTHOR]

The introductory part of the article presents the regulatory framework from Romania and European Union regarding photovoltaic systems implementation. Then, the paper displays aspects of the on-grid and off-grid photovoltaic systems, their general arrangements, costs, advantages, and disadvantages. The article is concluded with a comparative efficiency study of the two systems. These photovoltaic systems can be easily adapted for use in the naval domain, and they fulfil the European Union's 'green deal' requirements related to emissions. [ABSTRACT FROM AUTHOR]

This paper proposes a renewable energy hybrid power system that is based on photovoltaic (PV) and wind power generation and is equipped with Superconducting Magnetic Energy Storage (SMES). Wind and solar power generation are two of the most promising renewable power generation technologies. They are suitable for hybrid systems because they are environmentally friendly. However, like most renewable energy sources, they are characterized by high variability and discontinuity. They generate a fluctuating output voltage that damages the machines that operate on a stable supply. Therefore, the energy storage system SMES with the function to reduce output voltage fluctuation problems is introduced. SMES is found to be the most effective energy storage device as a result of its quick time response, high power density, and high energy conversion efficiency. In this paper, modeling of a hybrid system with SMES is built using MATLAB/Simulink. Blocks such as the wind model, PV model, and energy storage model are built separately before combining into a complete hybrid system with SMES. Varying wind speed and solar irradiance values are taken as the input parameters. The obtained results from the simulation reveal that a system with SMES is more reliable than a system without SMES. [ABSTRACT FROM AUTHOR]

Problem definition: More than 99% of the new power generation capacity to be installed in the United States from 2023 to 2050 will be powered by wind, solar, and natural gas. Additionally, large-scale battery systems are planned to support power systems. It is paramount for policymakers and electric utilities to deepen the understanding of the operational and investment relations among renewable, flexible (natural gas-powered), and storage capacities. In this paper, we optimize both the joint operations and investment mix of these three types of resources, examining whether they act as investment substitutes or complements. Methodology/results: Using stochastic control theory, we identify and prove the structure of the optimal storage control policy, from which we determine various pairs of charging and discharging operations. We find that whether storage complements or substitutes other resources hinges on the operational pairs involved and whether executing these pairs is constrained by charging or discharging. Through extensive numerical analysis using data from a Florida utility, government agencies, and industry reports, we demonstrate how storage operations drive the investment relations among renewable, flexible, and storage capacities. Managerial implications: Storage and renewables substitute each other in meeting peak demand; storage complements renewables by storing surplus renewable output; renewables complement storage by compressing peak periods, facilitating peak shaving and displacement of flexible capacity. These substitution and complementary effects often coexist, and the dominant effect can alternate as costs change. A thorough understanding of these relations at both operational and investment levels empowers decision makers to optimize energy infrastructure investments and operations, thereby unlocking their full potential. Funding: This research was supported in part by Lilly Endowment, Inc., through its support for the Indiana University Pervasive Technology Institute. This research was also supported by Kelley School of Business, Indiana University, and Haslam College of Business, University of Tennessee. O. Q. Wu thanks Grant Thornton for their generous support. Supplemental Material: The online appendix is available at https://doi.org/10.1287/msom.2023.0068. [ABSTRACT FROM AUTHOR]

In this paper, stochastic synchronization of the wind and solar energy using energy storage system based on real-time pricing in the day-ahead market along with taking advantage of the potential of demand response programming has been analyzed. Since renewable energies, loads and prices are uncertain, and planning is based on real-time pricing, the optimal biding proposition considers the wind power, solar system, and energy storage system. Uncertainty is addressed to solve the bidding strategy in a day-ahead market for optimal wind and PV power and optimal charging for energy storage. Batteries are the most promising device to compensate for the fluctuations of wind and photovoltaic power plants to mitigate their uncertainty. In general, using MILP is a suitable approach to address uncertainty as long as a linear formulation is acceptable for modeling either with continuous variables or integer ones. By setting some scenarios to formulate market prices, imbalance of energy, wind and solar system, the uncertainty problems could be easily solved by MILP solver. The model created enables the retailer to realize the potentials of the demand response program and exploit high technical and economic advantages. To ensure fair prices, a set of regulating constraints is considered for sales prices imposed by the regulation committees. A model is presented to optimize the electricity trading strategy in the electricity market, considering the uncertainty in the wholesale market price and the demand level. The retailer considered in this paper is a distribution company that is the owner and operator of the networks and operates under real-time pricing regulations. To model demand response, the elasticity coefficient is used. The proposed solution is implemented on a standard 144-bus sample network using a nonlinear integer programming method. The presented method results provide helpful and valuable information based on the optimal method proposed by the retailers considering the demand response program and real-time pricing system. [ABSTRACT FROM AUTHOR]

Penetration of renewable energy resources (RERs) in the power grid continues to increase as we strive toward a greener environment for the future. While they have many advantages, most RERs possess little or no rotational kinetic energy, thereby threatening the frequency stability of future power grids. Energy storage systems (ESSs) can be used to mitigate this problem, as they are capable of providing virtual inertia to the system. This paper proposes a novel analytical approach for sizing ESSs to provide inertial support to the grid and maintain frequency stability in presence of RERs. This method analytically estimates the total inertia of the system using probability distributions of the outage states of conventional generators and RERs. RERs are modeled as multi-state units, considering the variability of their output power due to changes in weather conditions and also the forced outages of their equipment. The ESS is utilized to provide virtual inertia to the grid in the form of active power once the estimated system inertia falls below the minimum required during a disturbance. The efficacy of the proposed approach is tested on the IEEE 39 bus system and the results obtained by the analytical approach are validated using Monte Carlo simulation. [ABSTRACT FROM AUTHOR]

In the modern world, the consumption of oil, coal natural gas, and nuclear energy has been causing by a serious environmental problem and an ongoing energy crisis. The generation and consumption of renewable energy sources (RESs) such as solar and wind tidal, can resolve the problem but the nature of the RESs is fluctuating and intermitted. This evolution brings a lot of challenges in the management of electrical grids. The paper reviewed the advancements in energy storage technologies for the development of a smart grid (SG). More attention was paid to the classification of energy storage technologies based on the form of energy storage and based on the form of discharge duration. The evaluation criteria for the energy storage technologies have been carried out based on technological dimensions such as storage capacity, efficiency, response time, energy density, and power density, the economic dimension such as input cost and economic benefit; and the environmental dimension such as emission and stress on ecosystem, social demission such as job creation and social acceptance were also presented in this paper. [ABSTRACT FROM AUTHOR]

Data centers are among the fastest growing industries in the United States economy in terms of IT service and usage of data. However, data centers consume an excessive amount of energy that contributes to huge energy costs and CO2 emissions; thus, they face challenges in energy cost savings and making a positive impact on the environment. Therefore, data centers have been striving to: 1) improve energy efficiency in server operations by applying server provisioning techniques, and 2) utilize renewable energy and energy storage for power procurement. Although data centers have obtained financial and environmental benefits from the aforementioned efforts, there still exists significant room for improvement by facilitating demand response based on the co-optimization of server operations and power procurement, which has not been well implemented in the current practice. The main objective of this paper is a new holistic approach that considers server operations and power procurement simultaneously for implementing demand response. Also, this paper develops a decision-making model based on two-stage stochastic programming to successfully address the inherent stochastic nature and demonstrate the impact of the proposed model via numerical experiments. The proposed model is designed to support practitioners’ strategic and operational decision-making for demand response in data centers. [ABSTRACT FROM AUTHOR]

Smart energy networks provide an effective means to accommodate high penetrations of variable renewable energy sources like solar and wind, which are key for the deep decarbonisation of energy production. However, given the variability of the renewables as well as the energy demand, it is imperative to develop effective control and energy storage schemes to manage the variable energy generation and achieve desired system economics and environmental goals. In this paper, we introduce a hybrid energy storage system composed of battery and hydrogen energy storage to handle the uncertainties related to electricity prices, renewable energy production, and consumption. We aim to improve renewable energy utilisation and minimise energy costs and carbon emissions while ensuring energy reliability and stability within the network. To achieve this, we propose a multi-agent deep deterministic policy gradient approach, which is a deep reinforcement learning-based control strategy to optimise the scheduling of the hybrid energy storage system and energy demand in real time. The proposed approach is model-free and does not require explicit knowledge and rigorous mathematical models of the smart energy network environment. Simulation results based on real-world data show that (i) integration and optimised operation of the hybrid energy storage system and energy demand reduce carbon emissions by 78.69%, improve cost savings by 23.5%, and improve renewable energy utilisation by over 13.2% compared to other baseline models; and (ii) the proposed algorithm outperforms the state-of-the-art self-learning algorithms like the deep-Q network. [ABSTRACT FROM AUTHOR]

This study considers the current state of hydropower in Poland and the legal and environmental conditions for its development. The research objective was to provide insights into the future of hydropower in Poland. An attempt was made to determine the direction of hydropower development in Poland by 2050, taking into account the requirements of the European Green Deal. The basic method used is logical argumentation, which is in turn based on a critical analysis of planning documents and scientific papers. Statistical data on the production and consumption of hydropower were also analysed. Currently, Poland's potential for hydropower production is not being fully exploited. The main reasons for this are a lack of political support and socio-ecological issues associated with the need to take over inhabited areas or areas of high natural value. The analysis of the state of hydropower in Poland indicates that urgent intervention is required in many areas. This applies, especially, to issues of the control, modernisation and technical condition of hydropower plants and damming facilities. The potential for the development of hydropower in Poland is assessed to be very small. Environmental, socio-economic and legal conditions are unfavourable to the construction of new, large hydropower plants. The exception is pumped-storage power plants, which, acting as energy storage facilities, should in the future constitute an important element of the Polish energy system. The possibility of using defunct lignite mining pits for this purpose is indicated. It is shown that some of Poland's former lignite mines are also conveniently located. The possible beneficial impact of building pumped-storage power plants into the water ecosystem of central Poland is emphasised. [ABSTRACT FROM AUTHOR]

The goal of this review is to offer an all-encompassing evaluation of an integrated solar energy system within the framework of solar energy utilization. This holistic assessment encompasses photovoltaic technologies, solar thermal systems, and energy storage solutions, providing a comprehensive understanding of their interplay and significance. It emphasizes the importance of solar energy as a renewable resource and its role in addressing global energy demand and mitigating climate change. The review highlights the significance of advancements in various solar energy technologies, focusing on their environmental benefits, including greenhouse gas emissions reduction and air and water pollution mitigation. It explores the evolution of photovoltaic technologies, categorizing them into first-, second-, and third-generation photovoltaic cells, and discusses the applications of solar thermal systems such as water heaters, air heaters, and concentrators. The paper examines key advancements in energy storage solutions for solar energy, including battery-based systems, pumped hydro storage, thermal storage, and emerging technologies. It references recent published literature to present findings on energy payback time, carbon footprint, and performance metrics. Challenges to widespread adoption are discussed, including cost and economic viability, intermittency, environmental impacts, and grid integration. Strategies to overcome these challenges, such as cost reduction, policy support, energy storage integration, and sustainable practices, are presented based on published literature. By bridging gaps in existing literature, this comprehensive resource aims to equip researchers, policymakers, and industry professionals with insights into forging a sustainable and renewable energy future. [ABSTRACT FROM AUTHOR]

This paper presents a techno-economic analysis of 'Picogrid' in hilly remote areas of North-East India, where availability of conventional grid power is either none or limited. A Picogrid is a small microgrid (typically a few tens of kW) containing renewable energy sources like solar, wind, small hydro etc. with battery based energy storage of limited capacity. A hybrid solar PV-Hydro based Picogrid of 7.2 kW capacity in a remote hilly area is analyzed, where the solar irradiance varies between 3.5 and 6.2 kWh/Day/m2, a water fall head lies between 1 and 30 m and water flow rate varies from 100 to 50,000 L/h. The study reveals that, the annual total energy generation varies between 1200 and 5000 kWh/kW/Year. Whereas the annual average daily yield and Capacity Utilization Factors for such system are 9 kWh/kWp/Day and 40%, respectively at highest possible water head and flow rate as mentioned above. The optimized Picogrid system is shown to have a levelised cost of electricity of 1.4 INR (0.017 USD) and 1.8 INR (0.022 USD) per kWh for 100% and 30% equity investment, respectively. The energy produced by these methods can be provided in rural areas thereby making electricity and revenue producing probabilities concurrently. [ABSTRACT FROM AUTHOR]

The variability of renewable energy generation and its mismatch with demand may lead to curtailment issues, which necessitates the deployment of energy storage on a significantly larger scale. A‐CAES is a promising technology for its green ability and technology maturity to serve as grid's load following. However, previous research mainly focuses on system analysis and core component optimal, and the performance of A‐CAES when constructing with renewable resources has not been fully addressed. In this paper, a comprehensive evaluation on A‐CAES is presented based on an annual photovoltaic (PV) output in western China. The A‐CAES is modeled from the systematic perspective and the PV output is classified into four types (sunny, mostly‐sunny, mostly‐cloudy, and cloudy). First, the performance with different weather and different rated power of A‐CAES is fully investigated. Then, performance availability with different rated power has been proposed—the optimal condition occurs with average 5.936 MWh/day capacity and 53.49% efficiency on 1800 kW rated power. The evaluation framework is suitable for evaluating the role of CAES with other sources and such result provides a reference for A‐CAES designing and further application. [ABSTRACT FROM AUTHOR]

As environmental pollution deteriorates, the acceleration of decarbonization worldwide is underway. Several countries, including Korea, are incorporating new and renewable energy into existing systems, and various methods of decarbonization are being researched. With changes in the control environment, the expansion of the system linkage of new and renewable energy can cause system instability problems. This paper introduces an operation plan that uses the fast response characteristics of energy storage system(s) (ESS) to improve stability and review system stability as a result of the expansion of new and renewable energy on Jeju Island. Frequency stability was ensured through an analysis of frequency response characteristics in the event of a system accident, and an efficient ESS operation plan was simulated by changing the ESS parameters. Through this simulation, stable ESS operation and hunting in the frequency recovery process were minimized through cooperation between the existing and new ESS via a wide dead-band range and speed adjustment rate correction, and the lowest frequency was improved. [ABSTRACT FROM AUTHOR]

In this paper, the modeling of storage elements and a unified theory liberated of the I–V characteristics of a specific technology is developed. First, the definition of an ideal storage element with limited energy capacity is presented, then the semiideal storage properties are discussed. The addition of power conservative two-port network denoted POPI (Pout = Pin) is added in order to define a flexible storage element in terms of characteristics. The paper demonstrates the theory by examples of storage elements integrated in power electronics systems. The ideas and methodology presented in this work can be applied to power electronics applications as well as power systems, smart grids, and microgrids, where storage is an important factor. [ABSTRACT FROM AUTHOR]

A new three-level bidirectional dc–dc converter configuration for the battery and supercapacitor (SC) energy storage systems in dc microgrids is presented in this paper. The PI-based control method is implemented to operate the proposed converter with hybrid energy storage system. Furthermore, joint control is utilized to obtain rapid dc-link voltage restoration and effective power sharing between battery and SC based on their respective characteristics. The system operating principle, controller design, stability analysis, simulation studies, and experimental studies are presented in this paper. The proposed three-level bidirectional dc–dc converter configuration can effectively integrate the battery and SC with the bidirectional power flow. The proposed control method provides the effective participation of the SC system which reduces the stress on the battery system. The presented converter configuration is effective in reducing the stress on the power semiconductors and provides better performance with smaller passive components. The experimental platform is built to test and validate the three-level bidirectional dc–dc converter and the proposed control method for the HESS. [ABSTRACT FROM AUTHOR]

The use of renewable energy for desalination started in the 1980s, in order to provide a sustainable water supply in windy/sunny areas with water shortages. Nevertheless, this initiative has been generally limited to the R&D field and prototypes, with few units operating under real conditions. The research tradition in this field carried out by the Canary Islands Institute of Technology, based on pilot facilities, resulted in wide expertise on practical issues, as well as a deep knowledge on the state of the art. This paper deals with the most relevant technical aspects to be considered in the optimal design and operation of wind/photovoltaic (PV)-powered reverse-osmosis (RO) systems, focusing on practical indications: appropriate pre-treatment, the use and selection of the RO energy recovery system (ERD), the selection of an energy storage system, key recommendations for the O&M actions in wind- and PV-powered RO systems (extracted from the experience of operating different units in remote locations (PV and RO) and coastal areas (wind and RO)), and an identification of the pros and cons of hybrid systems. A selection of economic data is given, indicating the main aspects of the minimization of the cost of water. Finally, the paper mentions the latest advances in the involved technologies. [ABSTRACT FROM AUTHOR]

Electric microgrids based mainly on renewable energies have seen a big expansion in recent years due to the great advantages they present against fossil fuels. Nowadays different governments are becoming aware of the use of environmentally friendly energies, so progressive investment has been granted to the consumers in Spain. Many microgrids have been installed in both connected and isolated circumstances, and this fact brings new challenges regarding the technical and economic points of view. This study aims to delve into electrical microgrids based on renewable energies applied in industrial facilities through a review of the literature associated with the study of general microgrids. It later focuses on the relationships between renewable energies and industrial environments. A brief reference is made to the use of energy storage systems in industrial installations depicting the most used systems. This paper presents a review of the state of the art of microgrids from distributed energy resources technologies to industrial microgrids optimization, with the primary objective of providing insight on current trends and directions in research and further identifying areas in need of further development. [ABSTRACT FROM AUTHOR]

Due to the volatile nature of renewable energy sources (RES), energy storage systems (ESS) are the primary impetus for increased dependence on RES in current power networks. Because of their quick responsiveness and rapid transition from charge to discharge in less than 1 ms, batteries are necessary even in the presence of alternative storage devices. Lithium-ion batteries (LIBs) have demonstrated their viability as ESS for RES. Given the significance of LIBs, it was vital to correctly and effectively quantify their costs in energy systems. Most studies did not offer a true real-world assessment of these batteries' aging but instead averaged their performance indices, which vary substantially depending on the system's working circumstances such as temperature, voltage, state of charge, and current level. Failure to use precise values for each charging/discharging operation might result in disastrous judgments and future techno-economic issues. This paper provides a novel and highly accurate piecewise modeling of LIBs for each charging and discharging operation based on real-world operational conditions. This novel aging model is used for calculating hourly aging and its impact on energy costs. The musical chair algorithm (MCA) is used to determine the optimal parameters' values of the LIB's model and the appropriate size of autonomous hybrid RES. When compared to other optimization techniques, the findings of optimal parameter determination using MCA revealed an 80% reduction in convergence time and better accuracy. The novel proposed aging model of the batteries predicts a 60% cost share of the battery, meanwhile, the existing strategy predicts 51% only. The levelized cost of energy is $0.1291/kWh and $0.0731/kWh for the new proposed aging model and existing strategy, respectively. [ABSTRACT FROM AUTHOR]

Vanadium Flow Batteries (VFBs) are a stationary energy storage technology, that can play a pivotal role in the integration of renewable sources into the electrical grid, thanks to unique advantages like power and energy independent sizing, no risk of explosion or fire and extremely long operating life. The first part of this paper presents the main features and the basic performance parameters of VFB, which determine their electric, hydraulic, thermal, and aging feature. The latter part outlines the strengths and weaknesses of the technology, the services that it can provide to the grid, and a short economic analysis. After presenting the fundaments of the technology, prospects and trends of VFBs deployment are outlined. Most of the considerations highlighted in this paper are inspired to studies performed on an industrial-size VFB operated at the Electrochemical Energy Storage and Conversion Lab (EESCoLab) at the University of Padua (Italy). [ABSTRACT FROM AUTHOR]

With the large-scale access of renewable energy, the randomness, fluctuation and intermittency of renewable energy have great influence on the stable operation of a power system. Energy storage is considered to be an important flexible resource to enhance the flexibility of the power grid, absorb a high proportion of new energy and satisfy the dynamic balance between the supply and demand of a system. At present, the cost of energy storage is still high, and how to achieve the optimal energy storage configuration is the primary problem to be solved. Therefore, the current research progress in energy storage application scenarios, modeling method and optimal configuration strategies on the power generation side, grid side and user side are summarized in this paper. On this basis, the shortcomings that still exist of energy storage configuration research are summarized, and the future research direction for energy storage configuration is prospected. This review can provide reference for the latest development and future research and innovation direction for energy storage configuration. [ABSTRACT FROM AUTHOR]

With the strong advancement of the global carbon reduction strategy and the rapid development of renewable energy, compressed air energy storage (CAES) technology has received more and more attention for its key role in large-scale renewable energy access. This paper summarizes the coupling systems of CAES and wind, solar, and biomass energies from the perspective of system topology, and points out the advantages and limitations of each system. It is shown that the coupling of wind energy and CAES is mainly combined in series and in parallel, and sometimes part of the wind power can be converted into thermal energy when coupled to CAES. The coupling between solar heat and CAES is an important form of coupling between solar energy and CAES. Solar-heat-coupled CAES mainly uses solar energy to heat expander inlet air. The coupling forms of solar energy and CAES are based on various CAES forms, various heat heating sequences, reheating, bottom cycle, and other factors. The combination of biomass and CAES is generally based on biomass gasification power generation technology. In the future, a wind–solar–CAES multiple coupling system is expected to become a promising large-scale form for the utilization of renewable energy, and this integrated system has great potential as a system configuration, but has some technical challenges. [ABSTRACT FROM AUTHOR]

This paper focuses on an industrial application where renewable power produced by photovoltaic panels is exploited to feed a pneumatic transport plant. The proposed system requires the careful management of the energy flows involved since it includes the interaction with the electric grid and with an electrochemical storage (battery) rather than the correct choice of the photovoltaic panel and battery itself. A dedicated control system needs to be developed in order to accord together these energetic flows, also providing a degree of flexibility to implement different control logics. The methodology employed in the research is simulation, which through the construction of a model in Matlab Simulink is able to reproduce the behavior of the system components and their energetic interactions for a long time period. The aim of the research is to provide a tool for assessing the energetic convenience of different battery–PV panel combinations. Moreover, an economical assessment of the proposed system is provided and compared to the traditional setup. Simulation results show that the proposed system provides energy savings with respect to a traditional grid-powered plant. The economic assessment shows that the system becomes convenient over the traditional setup within a time frame compatible with an average PV panel's useful life. [ABSTRACT FROM AUTHOR]

Given the various aspects of climate change and the growing demand for energy, energy efficiency and environmental protection have become major concerns worldwide. If not taken care of, energy demand will become unmanageable due to technological growth in cities and nations. The solution to the global energy crisis could be an advanced two-way digital power flow system that is capable of self-healing, interoperability, and predicting conditions under various uncertainties and is equipped with cyber protections against malicious attacks. The smart grid enables the integration of renewable energy sources such as solar, wind, and energy storage into the grid. Therefore, the perception of the smart grid and the weight given to it by researchers and policymakers are of utmost importance. In this paper, the studies of many researchers on smart grids are examined in detail. Based on the literature review, various principles of smart grids, the development of smart grids, functionality of smart grids, technologies of smart grids with their characteristics, communication of smart grids, problems in the implementation of smart grids, and possible future studies proposed by various researchers have been presented. [ABSTRACT FROM AUTHOR]

Recently, renewable energy resources (RESs) have been utilized to supply electricity to remote areas, instead of the conventional methods of electrical energy production. In this paper, the optimal design of a standalone hybrid RES comprising photovoltaic (PV), wind turbine (WT), and biomass sources as well as an energy storage system, such as a hydro-pumped storage system, is studied. The problem of the optimal sizing of the generating units in the proposed energy system is formulated as an optimization problem and the algorithms heap-based optimizer (HBO), grey wolf optimizer (GWO), and particle swarm optimization (PSO) are applied to achieve the optimal sizing of each component of the proposed grid-independent hybrid system. The optimization problem is formulated depending on the real-time meteorological data of the Ataka region on the Red Sea in Egypt. The main goal of the optimization process is to minimize the cost of energy (COE) and the loss of power supply probability (LPSP), while satisfying the constraints of system operation. The results clarify that the HBO algorithm succeeded in obtaining the best design for the selected RE system with the minimum COE of 0.2750 USD/kWh and a net present cost (NPC) of USD 8,055,051. So, the HBO algorithm has the most promising performance over the GWO algorithm in addressing this optimization problem. [ABSTRACT FROM AUTHOR]

Battery-based Energy Storage Transportation (BEST) is the transportation of modular battery storage systems via train cars or trucks representing an innovative solution for a) enhancing Variable Renewable Energy (VRE) utilization and load shifting, and b) providing a potential alternative for managing transmission congestions. This paper focuses on point b) and proposes a long-term transmission-planning model coordinated with both stationary and mobile storage units. The planning-problem objective function minimizes the total system cost, i.e., the sum of i) the investment cost of candidate transmission lines, stationary and mobile storage systems, and ii) the operation cost, including conventional generating units fuel consumption, load shedding penalty and BEST transportation costs. An alternative approach for BEST vehicle scheduling problem is implemented. The contribution lies in the accomplishment of the spatial-temporal scheduling of the mobile storage units by including the Number-of-nonzero mathematical function in the optimization model set of constraints instead of using additional binary variables as generally accomplished. The identification of either storage systems optimal location, or both optimal location and size of storage systems is also allowed. BEST usefulness is analyzed and discussed for a test-system emulating a reals system in China-Northwestern-grid with high VRE penetration divided in five regional areas, of which the most promising one for BEST implementation is identified. [ABSTRACT FROM AUTHOR]

This paper proposes a hybrid control method based on model predictive control (MPC) and iterative learning control (ILC) for the hybrid energy storage system (HESS) in the application of islanded microgrid with photovoltaic (PV) generation. The hybrid method helps to deal with the sudden change in generation and load power demands. MPC aims to regulate the current of the battery and the supercapacitor (SC) to track the dynamic current references. An improved quadratic programming algorithm is proposed to reduce the iterations in online optimization. To compensate for the steady-state error caused by the power loss in the power electronic devices, a controller based on ILC is designed to correct the dynamic current references of HESS. Simulation results are used to verify the proposed algorithm. Validations using hardware experimental results substantiate the improved performance of the proposed control method in terms of reduced voltage regulations. [ABSTRACT FROM AUTHOR]

Summary: This paper deals with optimal multi‐stage power management and control coordinated with load shedding in interconnected microgrid (MG) with various renewable energy sources (RESs), namely: wind turbine, photovoltaic generator and concentrated solar power generator. Hybrid energy storage systems including electrical vehicles, fuel cells, redox flow batteries and superconducting magnetic energy storage have been introduced to improve the overall MG frequency dynamic performances in case of renewable energy integration and load disturbances. To improve the interconnected MG tie‐lines power control, flexible alternating current transmission systems are added. For an optimal and robust solution, an artificial intelligence strategy is proposed, combining a load frequency control‐based cascade Fuzzy‐proportional‐integral‐derivative controller with filter (PIDN). In doing so, a recently meta‐heuristic algorithm that mimics the social behavior of elephants in nature, named Elephant Herding Optimization, has been employed to optimize the Fuzzy‐PIDN controller gains. To show the effectiveness and superiority of the proposed control strategy, various scenarios are carried out. A comparative study in view of a settling time and peak over/undershoot has been performed. The obtained results demonstrate that the proposed control strategy gives good performances for MG power management and control under RESs integration and load disturbances scenarios. [ABSTRACT FROM AUTHOR]

Currently, electrical distribution networks (EDNs) have used modern technologies to operate and serve many types of consumers such as renewable energy, energy storage systems, electric vehicles, and demand response programs. Due to the variability and unpredictability of these technologies, all these technologies have brought various challenges to the operation and control of EDNs. In this case, in order to operate effectively, it is inevitable that effective power redistribution is required in the entire network. In this paper, a multi-objective based dynamic optimal network reconfiguration (DONR) problem is formulated using power loss and voltage deviation index considering the hourly variation of load, photovoltaic (PV) power, and electric vehicle (EV) fleet load in the network. This paper introduces recently introduced meta-heuristic butterfly optimization algorithm (BOA) and it's improve variant of self-adaptive method (SABOA) for solving the DONR problem. The simulation study of IEEE 33-bus EDN under different conditions has proved the effectiveness of DONR, and its adoptability for real-time applications. In addition, by comparing different performance indicators (such as mean, standard deviation, variance, and average calculation time) of 50 independently run simulations, the efficiency of SABOA can be evaluated compared with other heuristic methods (HMs). Comparative studies show that SABOA is better than PSO, TLBO, CSA and FPA in the frequent occurrence of global optimal values. [ABSTRACT FROM AUTHOR]

In this paper, the characteristics of the most popular energy storage systems are analyzed, and conclusions are made about the advantages and disadvantages of the different systems. [ABSTRACT FROM AUTHOR]

The system presented in this paper can change the energy storage landscape by having the advantages of a compressed air storage system and pump storage, as well as minimizing the disadvantages of these two systems. One of the advantages of this system compared to similar systems is the lack of combustion of natural gas. Correspondingly, for construction, it does not require specific specifications for the executive site, and control of the energy and heat of the system (due to the use of water as an operational fluid) is easier than similar systems. In addition, this system is very scalable and can be designed in low capacities to high capacities, energy analysis of this research to identify the basic and effective parameters of the system and determine the limitations and relationships between them. The amount of energy saved in the current research system compared to previous research is significant, and 92% efficiency can be achieved. The energy analysis of this research determined the effect of the parameters on each other and their limitations so that the path of its feasibility design was paved. [ABSTRACT FROM AUTHOR]

This paper proposes a novel electrolytic-free quasi-Z-Source Ćuk LED driver for automotive applications. Compared to the traditional Ćuk converter, the first merit of the novel converter is higher gain, which makes it apt to switch between multiple applications. Secondly, the proposed converter combines the inherent characteristics of LED load to operate in a wide range in Continuous Conduction Mode (CCM), so the inductors can assist in energy storage, and only small capacitance is required. Thirdly, inductors can be integrated and use only one core, and capacitors are electrolytic-free, which will benefit integration and long life. All merits are important to automotive application. Detailed analysis and design steps are presented. Then, with the help of the simulation software Saber, several key parts of the converter are simulated. Finally, a prototype controlled by the micro control unit stm32f103c8t6 is built, and the feasibility is verified by the experiment results. [ABSTRACT FROM AUTHOR]

Hydrogen energy storage system (HESS) has excellent potential in high-proportion renewable energy systems due to its high energy density and seasonal storage characteristics. After detailing the volatility of wind speed, irradiance and load, this paper proposes a bi-level optimization model to analyze the economic operation of the wind-photovoltaic-hydrogen hybrid system (WPH-HS). First, the relationship between the source-load output matching and operating conditions of HESS is studied, two evaluation indicators are described, which can be adjusted by wind-solar complementarity on the source side and demand response on the load side. Second, considering the levelized cost of storage (LCOS), the total annual cost (TAC) calculation method of WPH-HS is presented, and this paper provides a new hybrid optimization technology of chaotic search, particle swarm optimization and non-dominated sorting genetic algorithm2. Finally, the system is simulated with the MATLAB software to determine the optimal sizing of components and minimize the LCOS while ensuring the optimal TAC. The simulation results are elaborated in detail. In particular, the added source-load interaction reduces the TAC and LCOS by 7.3% and 10.3%. When two indicators reach 0.03 and 0.1745, the system is economically viable with the LCOS of 0.276 USD/kWh. The hybrid optimization algorithm can achieve better result in fewer iterations. • The cross-season utilization of the hydrogen energy storage system is discussed. • A price bi-level model about the levelized cost of storage and the total annual cost is established. • Evaluation indicators are presented to promote the source-load interaction. • Effects of wind speed, irradiance, and loads are investigated for the levelized cost of storage. • A hybrid optimization algorithm based on three common algorithms is designed. [ABSTRACT FROM AUTHOR]

This paper describes a multi-variable robust control scheme for frequency regulation in a diesel–photovoltaic–supercapacitor hybrid power generation system operating in stand-alone mode. The proposed control structure relies on a two-level architecture, with conventional PI-based current tracking controllers placed on the lower control level and receiving references from an H ∞ -control-based upper level. The specific engineering demands of microgrid operation are cast into an H ∞ control formalism. A rapid-prototyping test bench composed of a real supercapacitor-based energy storage system and an emulated diesel–photovoltaic–load grid is developed using real-time digital simulators, namely RT-LAB ® and dSPACE ® , in order to experimentally validate the proposed frequency robust control strategy under realistic operating conditions. [ABSTRACT FROM AUTHOR]

In this paper, we study the peak load reduction in a smart building integrating microgrid and present a comprehensive finite-horizon optimization problem formulated as a dual tracking control problem subject to the quadratic cost function. The smart building integrates a microgrid consisting of photovoltaic modules, battery bank, and plug-in electric vehicles (PEVs). The objective of the microgrid is to satisfy the PEVs load as well as to reduce the peak load of the building. The control strategy aims to take advantages of the microgrid to pay the minimum billing demand to the main grid according to the subscribed power rating. These objectives can be reached through exploiting power generated onsite, local energy storage system, and the operational flexibilities of the PEVs via the vehicle-to-building alternative. In this paper, we focus on the fundamental issue of exploring smart charge and discharge scheduling of PEVs to reduce the peak load of the building. The proposed model has been extensively simulated and tested through case studies using measured solar and load data under the Quebec electricity pricing. [ABSTRACT FROM AUTHOR]

This paper proposes a machine learning approach for placing control actuators to enhance dynamic performance in power systems with high penetration of renewable energy. The method transforms the placement problem into a classification problem by studying the relationship between system topological, physical and operational features, and dynamic performance related labels. The proposed framework includes four stages: power system setup; dataset creation; feature extraction and analytical model generation, and creating guidelines for system planners. Test results in the IEEE 39-bus system and the IEEE 118-bus system determine the most significant features including inertia, topological, and impedance distributions. This paper also contributes to providing general criteria and guidance for system planners to place the control resources for improving oscillation damping, voltage, and transient stability issues. [ABSTRACT FROM AUTHOR]

In this paper, we propose two novel coalitional game theory-based optimization methods for minimizing the cost of electricity consumed by households from a smart community. Some households in the community may own renewable energy sources (RESs) conjoined with energy storage systems (ESSs). Some other residences own ESSs only, while the remaining households are simple energy consumers. We first propose a coalitional cost optimization method in which RESs and ESSs owners exchange energy and share their renewable energy and storage spaces. We show that by participating in the proposed game these households may considerably reduce their costs in comparison to performing individual cost optimization. We further propose another coalitional optimization model in which RESs and ESSs owning households not only share their resources, but also sell energy to simple energy consuming households. We show that through this energy trade the RESs and ESSs owners can further reduce their costs, while the simple energy consumers also gain cost savings. The cost savings obtained by the coalition are distributed among its members according to the Shapley value. Simulation examples show that the proposed coalitional optimization methods may reduce the electricity costs for the RESs and ESSs owning households by 18%, while the sole energy consumers may reduce their costs by 3%. [ABSTRACT FROM AUTHOR]

Liquid organic hydrogen carriers (LOHC) can be used as a lossless form of hydrogen storage at ambient conditions. The storage cycle consists of the exothermic hydrogenation of a hydrogen-lean molecule at the start of the transport, usually the hydrogen production site, becoming a hydrogen-rich molecule. This loaded molecule can be transported long distances or be used as long-term storage due to its ability to not lose hydrogen over long periods of time. At the site or time of required hydrogen production, the hydrogen can be released through an endothermic dehydrogenation reaction. LOHCs show similar properties to crude oils, such as petroleum and diesel, allowing easy handling and possibilities of integration with current infrastructure. Using this background, this paper reviews a variety of aspects of the LOHC life cycle, with a focus on currently studied materials. Important factors such as the hydrogenation and dehydrogenation requirements for each material are analysed to determine their ability to be used in current scenarios. Toluene and dibenzyltoluene are attractive options with promising storage attributes, however their dehydrogenation enthalpies remain a problem. The economic feasibility of LOHCs being used as a delivery device were briefly analysed. LOHCs have been shown to be the cheapest option for long distance transport (>200 km), and are cheaper than most at shorter distances in terms of specifically transport costs. The major capital cost of an LOHC delivery chain remains the initial investment for the raw materials and the cost of equipment for performing hydrogenation and dehydrogenation. Finally, some studies in developing the LOHC field were discussed, such as microwave enhancing parts of the process and mixing LOHCs to acquire more advantageous properties. • Efficient hydrogen storage solution for sustainable energy transportation and storage. • Enables safe and cost-effective hydrogen transportation and distribution networks. • Promotes renewable energy integration through versatile and scalable storage capabilities. • Facilitates decarbonization efforts by enabling long-term, stable hydrogen supply chains. [ABSTRACT FROM AUTHOR]

This paper deals with a dynamical analysis of a supercapacitor based multilevel inverter. In Fact, applications for multi-level inverters based on supercapacitors include uninterruptible power supplies (UPS), grid-tied renewable energy systems, electric vehicles, and other power conversion systems where high-power quality and rapid energy transfer are important. These systems are the subject of ongoing research and development in the field of power electronics and energy storage, as they have the potential to enhance the performance and efficiency of various electrical and electronic applications. However, If the input voltage sources are fixed, this can limit the flexibility of the inverter, especially in terms of regulating the output voltage and adapting to load variations. This study is focused on the dynamic analyses which is crucial for designing, optimizing, and verifying the performance of supercapacitor-based multi-level inverters in various applications. Hence, the behaviour of the system was studied on a resistive load, material calculations showing the functioning of the circuit as well as simulations were performed for the positive phase of the sinusoid at the terminals of the charge. [ABSTRACT FROM AUTHOR]

In this paper, the present status of energy storage implementation and research in Arab countries (ACs) is investigated. The different technologies of energy storage are reviewed then projects and capacities of installed or planned energy storage systems in the ACs are summarized based on published literature. In ACs, the installed and planned capacity of pumped hydro storage is 4365 MW, while for battery storage it is 5597 MW. No compressed energy storage projects are installed or planned in the near future. Green hydrogen as a fuel is planned in Egypt, Algeria, and Morocco. Renewable energy as a main employer of energy storage is predicted for the next 30 years; similarly, energy storage capacity is forecasted for the next 30 years. To enhance energy storage implementation it is recommended to include energy storage in all new commercial renewable energy projects. In addition to creating a regulatory framework that encourages the development of energy storage schemes. To advance research in the energy storage, modeling and simulation of energy storage systems in residential, commercial, and industrial sectors are recommended. In addition, cold energy storage for cooling and air‐conditioning using phase change material to be investigated. [ABSTRACT FROM AUTHOR]

This paper presents a concept of mechanical design, for a slow-speed kinetic energy storage device. It is an attempt to present the problem of using the device to cooperate with small-scale household RES. Calculations allowing for selection of rotating mass along with determination of effective revolutions of the rotating mass are presented. The 3D model gives an overview of the main structural nodes of the device in the mechanical part. Due to large axial load resulting from the mass of the rotor and other components and subassemblies, a simple FEM simulation of the structure base was performed. Preliminary calculations of the magnetic bearing, acting as an axial bearing, were also carried out. [ABSTRACT FROM AUTHOR]

Indian electricity sector is undergoing a transition phase, where a massive quantum of 500GW of non-conventional energy is going to be integrated into the existing resources of conventional energy by 2030. However, these renewable sources like solar and wind are highly fluctuating in nature. Managing this renewable rich grid will be a challenge to the system operators. Also, as the predictability of the renewable energy is highly volatile in nature, existing energy pricing mechanism will need to be reviewed. Energy storage systems like batteries and pump storage are some promising technologies which will definitely help managing grid more efficiently. Presently maximum of energy need in our country is being sourced through conventional resources, majority from fossil fuels. Almost 89% of energy generated being transacted though long-term power purchase agreements between discoms/consumers and generators. Only about 11% of power is being transacted through energy exchanges. The trading volume through exchange is expected to be increased as Discoms are not showing less interest to go into long term PPA due to their financial burden. With the integration of highly variable renewable energy with grid in massive quantum, price volatility will be increased. A suitable change in energy pricing is required so that both the Discoms and generators can hedge their risk in renewable-rich volatile power market. Discoms/consumers with their power optimization tools can also participate in derivatives markets and hedge their risk. This will help Discoms to lower their power purchasing costs and prevent them from being saddled with the inflexibility of long-term PPAs as electricity demand profiles change. Discoms will have the flexibility to buy power based on demand. Under the proposed structure, long-term contracts in the physical (spot) market will be traded on power exchanges under the jurisdiction of the Central Electricity Regulatory Commission (CERC), while in the financial (derivatives) market contracts are set to be traded on commodity exchanges regulated by the Securities and Exchange Board of India (SEBI). CERC will help in designing electricity contracts and facilitate transactions of energy contracts. Physical and financial electricity markets will complement each other. This paper will analyse the possible impact of energy transition and introduction of electricity derivatives in India Power Market. [ABSTRACT FROM AUTHOR]

Virtual Power Plants (VPPs) are efficient structures for attracting private investment, increasing the penetration of renewable energy and reducing the cost of electricity for consumers. It is expected that the number of VPPs will increase rapidly as their financial return is attractive to investors. VPPs will provide added value to consumers, to power systems and to electricity markets by contributing to different services such as the energy and load-following services. One of the capabilities that will become critical in the near future, when large power plants are retired, is grid-forming capability. This review paper introduces the concept of grid-forming VPPs along with their corresponding technologies and their advantages for the new generation of power systems with many connected VPPs. [ABSTRACT FROM AUTHOR]

This paper presents a simulation of an insulated micro-grid system based on the three-level converters control for energy management. Different renewable power sources (wind turbine and Photovoltaic (PV) energy systems) are used to energize the micro-grid. However, a battery energy storage system (BESS) and a variable diesel generator are also used to improve the reliability of the system. The contribution of this research is focused on the power control method based on improving the quality of energy transfer, mastering dynamic interactions and maximum energy production from renewable energies to reduce the fuel consumption by the diesel. Firstly, the proposed control model for each renewable energy was carried out through simulation in the environments of Matlab and Simulink to test the robustness and performance. The second part of this research is dedicated to managing the sharing of power between load, generators, and storage systems by extracting the references of power. The three-level PWM rectifiers for variable speed diesel generators was used to maintain and control the DC bus voltage of the isolated micro-grid. The results obtained from simulations show a good correlation between static and dynamic systems even for fluctuating sun power and wind speed. [ABSTRACT FROM AUTHOR]

Different from low-temperature electrolysis systems, the large power consumption for the balance of plant (BOP) of the reversible solid oxide cell (RSOC) system for a high-temperature operating condition needs to be considered in the determination of the capacity configuration of the hybrid renewable energy (HRE) system. To address this issue, a power-based model of the RSOC system is developed and the corresponding capacity configuration strategy especially for the HRE system is also proposed in this paper. An optimization program of a hybrid energy system model composed of the wind turbines (WT), photovoltaic panels (PV), reversible solid oxide cell (RSOC) system, hydrogen storage tank (HST), and battery are presented to urge the minimization of the total system cost, power redundancy, and power shortage. Particle swarm optimization (PSO) algorithm is utilized to determine the optimum size and operational energy management within the system. The results show that after the regulation of the energy storage system, the power redundancy and shortage of the hybrid energy system are greatly reduced with the decreases by 85.08% and 64.42%, respectively. Moreover, the power mismatch is still significantly affected by seasons. It is also found that the energy storage efficiency of the RSOC system is within 20% due to the fact that part of the electric energy is consumed by the BOP to maintain the operation of the RSOC system. Thus, more improvements should focus on simplifying the BOP system of the RSOC system and reducing the excess power consumption in the future. [ABSTRACT FROM AUTHOR]

This paper proposes a buffered microgrid with a modular grid interface consisting of a modular back-to-back converter. The proposed method provides a flexible strategy that enables both the load and generation expansion of the microgrid, with no sizing constraints on the initial stage. The method maintains the physical separation of the buffered microgrid from the grid by using back-to-back converters, which ensures a safe, secure and seamless operation in both islanded and grid-connected operation modes. The proposed modular structure allows an energy exchange prioritization either between the energy storage systems and the grid or between the energy storage units themselves, depending on the recommended/desired operational strategy. The prioritizations are achieved by using sets of dead zones in the control of the interfacing converters. In order to control the voltage and frequency, an inverse-droop-based dq-frame current control method was implemented in PSCAD/EMTDC to substantiate the proposed method. The simulation results of different scenarios show the operational flexibility, control simplicity and communication-free operation of the microgrid with different types of sources. [ABSTRACT FROM AUTHOR]