Integration Of Energy Storage Systems Research Articles

A comprehensive study on reliability performance of Photovoltaic-battery-based microgrids under different energy management strategies

As the demand for power reliability keeps rising in modern society, the integration of energy storage systems into power networks increases at an unprecedented rate. Meanwhile, reliability analysis and enhancement of a power network attracts more and more attention. This paper explores the impact of four different energy management strategies (EMSs) on the reliability of microgrids, which play an important role in future distribution networks. The reliability performance is analysed on different levels, including converter interfaces and battery storage units on device level as well as power supply reliability on system level. The numerical analysis has shown that the employed EMS can remarkably affect the reliability indices of the system. The battery lifetime can be increased by more than 50% and annual energy loss can be reduced by up to 92%. Since the economic decision-making depends on the components lifetime and overall system performance, this paper provides deep insights for power engineers to properly design, plan and control future microgrids.

Review of Energy Storage and Energy Management System Control Strategies in Microgrids

A microgrid (MG) is a discrete energy system consisting of an interconnection of distributed energy sources and loads capable of operating in parallel with or independently from the main power grid. The microgrid concept integrated with renewable energy generation and energy storage systems has gained significant interest recently, triggered by increasing demand for clean, efficient, secure, reliable and sustainable heat and electricity. However, the concept of efficient integration of energy storage systems faces many challenges (e.g., charging, discharging, safety, size, cost, reliability and overall management). Additionally, proper implementation and justification of these technologies in MGs cannot be done without energy management systems, which control various aspects of power management and operation of energy storage systems in microgrids. This review discusses different energy storage technologies that can have high penetration and integration in microgrids. Moreover, their working operations and characteristics are discussed. An overview of the controls of energy management systems for microgrids with distributed energy storage systems is also included in the scope of this review.

Optimal design and energy management of an isolated fully renewable energy system integrating batteries and supercapacitors

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

Efficiency Comparison of DC and AC Coupling Solutions for Large-Scale PV+BESS Power Plants

In large-scale photovoltaic (PV) power plants, the integration of a battery energy storage system (BESS) permits a more flexible operation, allowing the plant to support grid stability. In hybrid PV+BESS plants, the storage system can be integrated by using different power conversion system (PCS) layouts and different charge–discharge strategies. In the AC-coupling layout, the BESS is connected to the ac-side of the system through an additional inverter. In the DC-coupling layout, the BESS is connected to the dc-side, with or without a dedicated dc–dc converter, and no additional inverter is needed. Referring to a 288 MWp PV plant with a 275 MWh BESS, this paper compares the PCS efficiency between AC- and DC-coupling solutions. The power injected into the grid is obtained considering providing primary power-frequency regulation services. A charging and discharging strategy of the BESS is proposed to ensure cyclic battery energy shifting. The power flows in the different components of the system that are obtained under realistic operating conditions, and total energy losses and annual average efficiency are calculated accordingly. Finally, results show a higher efficiency of DC-coupling compared to the AC-coupling layout.

Integration of energy storage systems based on transcritical CO2: Concept of CO2 based electrothermal energy and geological storage

Energy storage systems are crucial for the massive deployment of renewable energy at a large scale. This paper presents a conceptual large-scale thermoelectrical energy storage system based on a transcritical CO2 cycle. The concept is developed through the analysis of three high-efficiency systems: renewable energy storage using a thermoelectric energy storage system based on a reversible heat pump; a CO2 storage system; and novel integration of energy storage using a reversible heat pump and geological injection of CO2. The latter system efficiently integrates energy and CO2 storage, taking advantage of the synergies between the operational requirements of both systems. The system uses CO2 captured in stationary sources as a working fluid to store energy from renewables. The energy is stored and recovered in geological formation and heat/cold tanks, with energy storage based on sensible or latent heat of ice and water. A fraction of the CO2 is expected to be permanently sequestered in the geological formation. The analysis of the time evolution of the system, under different operation profiles, shows the interest of the concept as a feasible integration for energy storage and CO2 capture based on renewable energy, with an electric-to-electric efficiency varying between 40 and 50 %.

Joint investment of community energy storage systems in distribution networks using modified Nash bargaining theory

The emergence of renewable energy technologies in distribution networks and microgrids has raised the importance of integrating energy storage systems into these grids. However, their high investment costs deter decision makers from effectively expanding these assets. In this paper, a cooperative community storage expansion plan is proposed as a bargaining problem between distribution company and private microgrids to jointly invest in energy storage systems. By doing so, each party takes a quota of shared investment costs and thus the burden of high investment costs is alleviated. A modified version of the Nash bargaining theory approach is proposed to implement the cooperative framework in a fair manner. Two cases of non-cooperation and cooperation are distinctively defined and the merits of cooperation are illustrated. The lead acid battery is considered as the storage candidate, for which a novel linearized lifetime model and replacement approach is also proposed. The bargaining results presented on a distribution network test case indicate that through the proposed cooperation, all players receive positive surpluses by decreasing their costs or increasing their revenues. Thus, both distribution company and microgrids would have incentives to participate in the proposed cooperation. Moreover, the superiority of the proposed modified Nash bargaining theory compared to conventional Nash bargaining theory in terms of cooperation fairness is illustrated. Finally, the ability of the proposed cooperative community storage expansion plan to effectively manage cooperative storage installations and replacements is demonstrated.

Advances in Si and SiC Materials for High-Performance Supercapacitors toward Integrated Energy Storage Systems.

Silicon (Si), as the second most abundant element on Earth, has been a central platform of modern electronics owing to its low mass density and unique semiconductor properties. From an energy perspective, all-in-one integration of power supply systems onto Si-based functional devices is highly desirable, which inspires significant study on Si-based energy storage. Compared to the well-known Si-anode Li-ion batteries, Si-based supercapacitors possess high power density, long life, and simple working mechanisms, which enables their ease of integration onto a wide range of devices and applications. Besides Si, silicon carbide (SiC), as a physicochemically stable wide-bandgap semiconductor, also attracts research attention as an energy storage material in harsh environments. In this review, a detailed overview of latest advances in materials design, synthesis methods, and performances of Si-based and SiC-based supercapacitors will be provided. Some successful integrated devices, future perspectives, and potential research directions are also highlighted and discussed.

Investigation of boiling heat transfer for improved performance of metal hydride thermal energy storage

The inherent nature concerning the intermittency of concentrating solar power (CSP) plants can be overcome by the integration of efficient thermal energy storage (TES) systems. Current CSP plants employ molten salts as TES materials although metal hydrides (MH) have proven to be more efficient due to their increased operating temperatures. Nonetheless, the heat exchange between the MH bed and the heat transfer medium used to operate a heat engine is a critical factor in the overall efficiency of the TES system. In this work, a computational study is carried out to investigate the performance of a magnesium hydride TES packed bed using a multiphase (boiling) medium instead of single-phase heat absorption methods. The boiling heat transfer behaviour is simulated by using the Eulerian two-fluid framework. The simulations are conducted at a transient state using SST-k-ω Reynolds-Averaged Navier-Stokes equations. It is observed that, unlike the single-phase heat collection method, the multiphase heat absorption method maintains a constant temperature in the heat transfer fluid throughout the reactor. Consequently, a higher temperature gradient is realised between the MH bed and heat transfer fluid (HTF), leading to improvements in the overall reaction rate of the hydrogenation process.

Comparative study of battery energy storage systems in a micro-grid based on real-time simulation

The penetration of the distributed energy resources particularly solar and wind power into the electrical system has been increasing, but the intermittent nature of these resources produces perturbations and instability in the electrical grid. Thus, integrating energy storage system into the power grids is one of the best solutions to improve the reliability with performance of electrical systems; ensure power balance and meet consumer demand. Different technologies of energy storage devices have been used to support the integration of renewable energy resources and contribute to improve either the effectiveness with the management of power operating system during critical situations such as power fluctuations in the electrical grid. The main objective of this work is to test the effectiveness of battery energy storage system in reducing active power fluctuations in presence of a perturbation in a micro-grid. In addition, a comparative study is carried out by comparing the response of different battery technologies which are used to support the electrical grid in order to verify the appropriate battery technology for power systems and particularly for energy management in micro-grids during power fluctuations, also, the evaluation of the behaviour, feasibility, performance and effectiveness of BESS is achieved by using real-time simulation.

Simultaneous optimal integration of photovoltaic distributed generation and battery energy storage system in active distribution network using chaotic grey wolf optimization

Goal. The integration of photovoltaic distributed generations in the active distribution network has raised quickly due to their importance in delivering clean energy, hence, participating in solving various problems as climate change and pollution. Adding the battery energy storage systems would be considered as one of the best choices in giving solutions to the mentioned issues due to its characteristics of quick charging and discharging, managing the quality of power, and fulfilling the peak of energy demand. The novelty of the proposed work is the development of new multi-objective functions based on the sum of the three technical parameters of total active power loss, total voltage deviation, and total operation time of the overcurrent protection relay. Purpose. This paper is dedicated for solving the allocation problem of hybrid photovoltaic distributed generation and battery energy storage systems integration in the standard IEEE 33-bus and IEEE 69-bus active distribution networks. Methodology. The optimal integration of the hybrid systems is formulated as minimizing the proposed multi-objective functions by applying a newly developed metaheuristic technique based on various chaotic grey wolf optimization algorithms. The applied optimization algorithms are becoming increasingly popular due to their simplicity, lack of gradient information needed, ability to bypass local optima, and versatility in power system applications. Results. The simulation results of both test systems confirm the robustness and efficiency of the chaotic logistic grey wolf optimization algorithm compared to the rest of the algorithms in terms of convergence to the global optimal solution and in terms of providing the best and minimum multi-objective functions-based power losses, voltage deviation and relay operation time values. Practical significance. Recommendations have been developed for the use of optimal allocation of hybrid systems for practical industrial distribution power systems with the renewable energy sources presence.

Concepts, Structure and Developments of High-Reliability Cyber-Physical Fusion Based Coordinated Planning for Distribution System

Coordinated control is imperative for the distribution network with the integration of wind power, photovoltaic system, and energy storage system. Meanwhile, the advanced automation terminal, intelligent control technology, and information communication technologies have greatly promoted the informatization of distribution networks which also increase the correlation between the physical system (primary system) and the cyber system (secondary system). Hence, it is critical to comprehensively coordinate the planning of the cyber-physical system for building a highly reliable power grid. This work summarizes a series of challenges brought by the highly coupled cyber-physical system, such as the primary and secondary collaborated planning models and solution algorithms. Then, the reliability assessment theories of cyber-physical systems and their application in distribution network planning models are introduced. Finally, three development directions of distribution network planning in the future are proposed, considering primary and secondary system coordinated planning.

Integration of energy storage system and renewable energy sources based on artificial intelligence: An overview

Energy storage technology plays a role in improving new energy consumption capacities, ensuring the stable and economic operation of power systems, and promoting the widespread application of renewable energy technologies. Several new developments, ideas, approaches, and technologies have been introduced into this area from fields including materials, knowledge manage, electricity, control, and artificial intelligence. Based on the technical characteristics of renewable energy, this study reviews the roles, classifications, design optimisation methods, and applications of energy storage systems in power systems. First, we introduce the different types of energy storage technologies and applications, e.g. for utility-based power generation, transportation, heating, and cooling. Second, we briefly introduce the states of an energy storage system, along with its operation processes and energy storage capacity. Third, a comprehensive review is conducted on artificial intelligence applications in regards to optimisation system configuration, and energy control strategy, along with the applicability of different energy storage technologies. Finally, several issues and insights are discussed, offering new inspiration and concepts for the future study of integrated energy storage systems.

Intelligent monitoring of small sized supercapacitor in wind-penetrated power system

This work pertains to integration of supercapacitor energy storage system with wind-penetrated two-area power system. A small-sized SCES device is incorporated in automatic generation control of each area. For robust and optimum usage of SCES, a customized neuro-adaptive predictive control model is developed using level 1 S-function coding. This model feeds reference power command to the converter of storage system with its voltage used as feedback loop. A step load disturbance reflecting load outage is introduced back to back in the power system. It is seen through simulation studies carried out in MATLAB Simulink Environment that there is significant improvement in frequency response and tie power deviations. SCES converter power limits are fully maintained; besides, SCES voltage and power response is also depicted.

A novel algorithm based on the combination of AC-OPF and GA for the optimal sizing and location of DERs into distribution networks

This article proposes an algorithm to obtain an optimal local solution for the network planning process related to the optimal integration of different renewable energy sources (RES) and different Battery Energy Storage Systems (BESS) into a distribution network (DN). The algorithm provides strategic information related to investment and operation costs regarding the type of technology, location, and sizing. The mathematical formulation is based on an AC optimal power flow (OPF) to ensure the network’s minimal stability conditions. Besides, through the use of linearization and a modified version of a genetic algorithm (GA), the algorithm proposed breaks the 24 h wall, used until now in the literature, and extend it to 8760 h, which represents a much more realistic scenario to define the storage and power generation capacity of a DN in a planning context. The algorithm has been tested in a modified version of the IEEE 33-bus considering two cases of study: an off-grid case and grid-connected case, to measure the CapEx and OpEx variability, achieving to show that a grid-connected system reduces the installed capacity of DG and BESS in 37.4% and the CapEx 22.8%. • A novel algorithm is presented for the optimal simultaneous integration of DG and BESS into DN in terms of capacity and location. • A feasible solution for 8760 h as a time horizon, which breaks the 24-hours wall of related literature. • A much more realistic sizing for DG and BESS for distribution network planning is obtained. • The impact of an Off-grid and Grid-connected system on the planning process in terms of CapEx/OpEx.

Rule-based adaptive control strategy for grid-forming inverters in islanded power systems for improving frequency stability

Operating isolated power systems with increasing shares of renewable energy sources requires the integration of battery energy storage systems in order to assure enhanced frequency regulation capabilities. The control mode of power converters interfacing battery energy storage systems to the grid can be based on grid-forming type structures given its superior performance with respect to the mitigation of network frequency disturbances. Nevertheless, in case of network faults, the interactions between existing synchronous units and the grid-forming type converters may adversely affect the global system behavior. Therefore, this paper addresses the study-case of a MW-scale isolated power system with large shares of converter-interfaced renewable generation, operating with both synchronous machines and a grid-forming type power converter. An optimal grid-forming control parameter tuning procedure considering different disturbances is presented, aiming to reduce the associated battery energy storage system power regulating effort following the disturbances. Moreover, it is proposed and discussed the need of a novel rule-based adaptive control solution to switch between different sets of control parameters used in grid-forming type converters depending on the network status following a fault-type disturbance. Extensive numerical simulations performed over different operating scenarios illustrate the performance of the proposed solution.

Medium-Voltage Converter Solution With Modular Multilevel Structure and Decentralized Energy Storage Integration for High-Power Wind Turbines

As the penetration of renewable energy generation increases, the importance of energy storage systems becomes evident since these systems can contribute for the preservation of the power system stability. Wind turbine owners can also benefit from having energy storage systems as they can increase their revenues. The fast growth of wind turbine power ratings will eventually lead to the requirement of higher voltage levels as well. Proper power electronic converters will be required to drive these systems. Converters with a modular multilevel structure are considered the state-of-the-art solution for high-power applications. These topologies allow for a flexible integration of energy storage systems in both centralized and decentralized ways. This article presents a new converter solution with a modular multilevel structure and decentralized energy storage integration suitable to drive high-power medium-voltage wind turbines. This converter presents important structural and control characteristics that allows for a straightforward integration of an energy storage system in such a way that the wind turbine driven by it can operate with high flexibility and in a dispatchable fashion, benefiting both the power system operator and the wind-power-plant owner.

A study on steam cycle optimization for integrating energy storage system to nuclear power plant

As the share of renewable energy will be increasing, there is a growing interest in flexible power sources and energy storage systems due to the intermittent nature of renewable energy. We propose the Energy Storage System (ESS) integrated Nuclear Power Plant (NPP) as a solution. The system operates on load-following by branching the mass flow from the steam cycle to the ESS without changing the reactor thermal output. However, the merging point can be different for heat storing ESS and work storing ESS because the outlet conditions of the ESS vary depending on the type of ESS. In this study, the merging points are categorized into two types, feedwater heater and condenser. At each merging point, cycle optimization is performed while increasing the branch flow into ESS. The optimization goal is to maintain the feedwater temperature at the inlet of a steam generator. The power output and energy delivered to the ESS according to the merging point are estimated. From this study, it was found that when 25% of the inlet mass flow rate to the low-pressure turbine is diverted to ESS, the overall output of the steam cycle is decreased by 44.17% for the heat conversion ESS and 49.95% for the work conversion ESS.

An integrated photovoltaic/wind/biomass and hybrid energy storage systems towards 100% renewable energy microgrids in university campuses

The incorporation of energy storing units into hybrid systems reallocates the excess electricity to meet demand requirements in the deficiency periods. This study seeks to determine the optimal size of a Photovoltaic (PV)/wind/biomass hybrid system with and without energy storage built on the base of boosting the demand–supply fraction (DSF) and the renewable energy fraction (FR) with a net present value larger than or equals to zero. The Generalized Reduced Gradient algorithm has been utilized in this study to evaluate the optimal components’ capacities of the proposed system. Middle East Technical University Northern Cyprus Campus was used as a case study. The proposed system consists of 1.79 MW PV, 2 MW wind and 0.92 MW biomass systems with 24.39 MWh pumped hydro storage system and 148.64 kWh batteries achieving FR of 99.59%, DSF of 98.86%, and a cost of electricity equals to 0.1626 $/kWh. The simulations results proved that the integration of a hybrid energy storage system with the PV/wind/biomass system ensures very high autonomy approaching almost 99%. Finally, considering the significant excess energy produced by the tri-hybrid system, this excess could also be allocated towards meeting the campus’s thermal and domestic hot water demands creating a polygeneration power system.

Dynamic performance enhancement of interconnected hybrid thermal power system in the presence of electric vehicles

The prolific integration of non-synchronous distributed energy resources and energy storage systems (EES) into thermal-dominated grids significantly impact the power system's total synchronous inertia (TSI). The TSI, in turn, affects the frequency response of the electrical grid (EG). Although the EES supports frequency regulation, the cost is a vital factor in determining their role. Lately, it is realized that incorporating plug-in hybrid electric vehicles (PHEVs) as auxiliary power sources can provide inertial support if penetrated in huge numbers into the EG. This work proposes a supply and demand variation approach that integrates EVs in load frequency control (LFC). The proposed LFC uses the biogeography-based optimization (BBO) algorithm. A parallel direct current (DC)-alternating current (AC) interconnected hybrid thermal power system (IHTPS) with different types of high voltage direct current (HVDC) tie-links in the presence of PHEVs is simulated. The settling time, oscillations, and first peaks are mainly analyzed for the considered HVDC tie-links. The results show that the virtual synchronous power-HVDC tie-link offers better dynamic performance than that of the other tie-link, proving EV's presence in improving the frequency response. Thus, the investigation demonstrates the BBO based LFC role in enhancing the dynamic performance of the IHTPS.

A conditional value-at-risk based planning model for integrated energy system with energy storage and renewables

Owing to the potential higher energy supply efficiency and operation flexibility, integrated energy system (IES), which usually includes electric power, gas and heating/cooling systems, is considered as one of the primary forms of energy carrier in the future. However, with the increasing complexity of multiple energy devices and systems integration, IES planning is facing a significant challenge in terms of risk assessment. To this end, an energy hub (EH) planning model considering renewable energy sources (RES) and energy storage system (ESS) integration is proposed in this paper, in which the risk is measured by Conditional Value-at-Risk (CVaR). The proposed IES planning model includes two stages: 1) investment planning on equipment types and capacity (e.g., energy converters, distributed RES and ESS) and 2) optimizing the potential risk loss in operation scenarios along with confidence level and risk preference. The problem solving is accelerated by Benders Decomposition and Improved Backward Scenario Reduction Method. The numerical results illustrate the proposed method’s effectiveness in balancing the potential operation risk and investment cost. Moreover, the effectiveness of reducing potential operation risk by introducing ESS and RES are also verified.