Design Of Energy Storage System Research Articles

On the Problem of Arrangement of Hybrid Energy Storage Systems

. Electric energy storage systems are widely used in electric transport, power engineering and in order to provide autonomous power supply and load regulation of power systems. One of the ways to increase the technical and economic efficiency of storage devices is their hybridization, i. e. the creation of storage devices consisting of blocks of different types of batteries. The special literature contains no systematic analysis of qualitative and quantitative effects of hybridization and corresponding methodological recommendations for choosing a scheme and evaluating the effectiveness of hybridization. In the present article, this issue is considered from a theoretical and methodological standpoint, recommendations are given for the design of storage devices serving solar or low-power wind farms. A brief overview of data on the cost of buffering electricity with lithium-ion, lead-acid batteries and supercapacitors is made. A method is proposed for determining the necessity and degree of hybridization of an energy storage device based on the simplest dependencies of the storage parameters on the degree of hybridization. The notions of the coefficient of synergetic effect of hybridization and the degree of internal buffering of electricity are introduced. A quantitative-and-qualitative model for evaluating the effectiveness of hybridization is presented. A methodological approach is proposed for calculating the degree of internal recovery and evaluating the coefficient of synergetic effect of hybridization. It is shown that, in general, the adding of supercapacitor unit to lithium-ion batteries a does not lead to a reduction in the cost of buffering electricity due to the high ratio of the cost of buffering with a supercapacitor to the cost of buffering with lithium-ion batteries. At the same time, the economic feasibility of using supercapacitors to compensate for high pulse loads can be determined on basis of the analysis of the frequency spectrum of the load graph of the storage unit. The developed models and approaches can be used in the design of electrochemical energy storage systems for specified operating conditions.

An adaptive multi-objective joint optimization framework for marine hybrid energy storage system design considering energy management strategy

The electric propulsion ship with the hybrid energy storage system (HESS) has environmental friendliness and significant advantages in terms of low fuel consumption. Due to the high maneuverability and load fluctuation of vessels, marine HESS design problem is nonlinear and multi-objective. Aiming at HESS design problem with complex working conditions during vessel practical operation process, and since there is a strong coupling between HESS and power allocation, in this paper an adaptive multi-objective joint optimization framework (AMJOF) for HESS design considering energy management strategy (EMS) is proposed. A multi-objective joint optimization method is introduced into the framework to achieve strong working condition adaptability and reach the most suitable energy management for marine HESS design with the lowest investment cost and minimum battery degradation. In addition, based on adaptive segmentation and frequency control, a novel EMS is proposed, which achieves efficient power allocation, and the evaluation indicator is introduced to quantify the performance of different optimization. The results indicate that the AMJOF can achieve excellent performance and find the optimal solution for operation of the ship.

Research on air‐cooled thermal management of energy storage lithium battery

AbstractBattery energy storage system occupies most of the energy storage market due to its superior overall performance and engineering maturity, but its stability and efficiency are easily affected by heat generation problems, so it is important to design a suitable thermal management system. Due to the huge scale, complex composition, and high cost of stationary energy storage systems, it is difficult to optimize its parameters and structures by direct experimental research. In order to explore the cooling performance of air‐cooled thermal management of energy storage lithium batteries, a microscopic experimental bench was built based on the similarity criterion, and the charge and discharge experiments of single battery and battery pack were carried out under different current, and their temperature changes were analyzed. The numerical simulation study of the thermal management system of the battery pack is carried out by using ANSYS Fluent software, and the numerical simulation results are compared with the experimental results to verify its feasibility. And the influence of structural and parametric factors such as inlet and outlet position, battery spacing, and inlet air volume on the performance of the air‐cooled thermal management system is explored by means of numerical simulation. The results show that the heat generation of the battery in the discharge process is higher than that of the charging process, and the air from the top of the battery pack can achieve a better cooling effect, and there is an optimal battery spacing to achieve the best cooling effect, and the research conclusion provides some reference for the optimal design of the actual stationary energy storage system.

Design and Evaluation Framework for Modular Hybrid Battery Energy Storage Systems in Full-Electric Marine Applications

In the context of the maritime transportation sector electrification, battery hybridization has been identified as a promising manner of meeting the critical requirements on energy and power density, as well as lifetime and safety. Today, multiple promising battery hybridization topologies have been identified, while there is not a level playing field enabling comparison between different topologies. This study bridges this gap directly by proposing a generic hybrid battery energy storage system (HBESS) design and evaluation framework in full-electric marine applications that accounts for the key design requirements in the system topology conceptualization phase. In doing so, generalized key component models, such as battery cell models, aging models, power converter models, and thermal models, are established. Additionally, given the selected key requirements in this study, the case study comparing one baseline monotype design and two HBESS topologies has shown the clear advantage of battery hybridization. Furthermore, we find that, depending on the topology selection and the specific load scenario being considered, power converter devices can also worsen the key performance indexes.

Design and off-design performance analysis of a liquid carbon dioxide energy storage system integrated with low-grade heat source

Nowadays, developing the renewable energy has become the worldwide consensus. Nevertheless, the intermittency and volatility of renewable electricity bring great challenges to the stability of the power grid. Liquid carbon dioxide energy storage is recognized as one of the most promising technologies to overcome these difficulties. In this paper, a liquid carbon dioxide energy storage system integrated with the low-grade heat source is proposed. Based on the preliminary geometric parameters of system components, investigations on the system design and off-design performances are carried out. Results of parametric analysis indicate that the pseudo-critical point corresponding to 8 MPa is recommended as the design point for compressor inlet, and the minimum value of LCOE could reach 9.49 cents/kWh. Under design conditions, the system exergy efficiency reaches 48.42% and the roundtrip efficiency is 63.60%. Moreover, 10.70 cents/kWh of the per unit generation cost is advantageous in the large-scale energy storage systems. With the variations of input power (70%∼120%) and output power level (50%∼100%), the surplus water ratio could reach 23.63% at 50% load level, while the variation range of exergy efficiency is 15.56%∼48.42%. Meanwhile, the roundtrip efficiency varies from 22.16% to 63.60% under off-design conditions, and the maximum value is achieved at the design point. All the results identify the feasibility of the integrated energy storage system.

THESEUS: A techno-economic design, integration and downselection framework for energy storage

Optimal selection of energy storage technologies is critical to ensure reliable integration of intermittent and often uncertain renewable energy in electricity grids. The consideration of a diverse set of energy storage technologies is required for a more sustainable deployment of energy storage. We present THESEUS (TecHno-Economic framework for Systematic Energy storage Utilization and downSelection), which is a comprehensive framework for the optimal selection, design and operation of energy storage systems. THESEUS includes rigorous models of major energy storage technologies at different maturity levels, such as thermal storage using phase-change materials or molten salt, cryogenic storage, mechanical storage in the form of compressed air and pumped hydro storage, chemical storage using hydrogen, and electrochemical storage in the form of lithium-ion, sodium sulfur and vanadium flow batteries. An illustrative case study on state-wide prospective energy storage shows that storage integration with fossil power plants could reduce the cost of meeting the grid energy demand by 20%, with mechanical storage as the best suited technology. Although high-temperature thermal storage has low storage efficiency, it is optimal for integration with renewable energy plants. In addition, Li-ion batteries are optimal for high ramping but low storage duration requirements. Such insights can enable the deployment of both existing and emerging energy storage technologies to facilitate a smooth transition to a clean energy future.

Influence of Geometric Parameters on the Charging process of PCM in Semi-circular thermal storages for energy management.

The limitation of intermittent and irregular supply of the solar energy systems can be compensated through utilization of thermal energy storage systems. The design of an efficient latent heat thermal energy storage system plays a huge role in determining the overall performance. Therefore, this study aims to investigate the effect of geometric parameters such as thermal charger interspacing and inclination angle on the charging performance of a PCM (phase change material) inside a semi-circular enclosure with two charging sources (renewable heat sources). A numerical analysis is performed using the enthalpy-porosity method. The system performance is assessed in terms of dimensionless flow parameters such as Fourier number, Rayleigh number, and Stefan number. The study shows that the variation of Rayleigh number significantly influences the natural convection in the fluid zone of a PCM. An increase of Rayleigh number from 1e4 to 5e5 reduced the overall melting time by more than half. In addition, the thermal charger interspacing and inclination angle both showed considerable effect on the flow physics which can cause significant expedition/delay of the melting process.

Application-driven level-of-detail modeling framework for occupant air-conditioning behavior in district cooling

Occupant behavior (OB) contributes significantly to uncertainties in the results of building performance simulation (BPS). However, a consensus regarding the appropriate level of detail (LoD) for OB modeling in BPS is yet to be reached. Hence, this study focuses on district cooling simulation applications. A systematic technical framework for determining the most appropriate LoD for modeling occupant air-conditioning (AC) use behavior is proposed herein. The framework includes three steps: defining applications and the key performance indicators (KPIs), defining comparable LoDs for AC use behavior modeling, and selecting LoDs based on KPI analysis. Appropriate LoDs for different applications are concluded. For the application related to total cooling demand evaluation, LoD O-1, representing average occupant with stochastic models, is recommended. For the design (sizing) of cooling equipment, LoD O-2, considering the diversity behaviors of occupants, is recommended. For the design of district thermal energy storage (TES) system, LoD O-2 is appropriate. For electricity pricing strategy-making, the most detailed LoD O-3 is recommended. The proposed analytics framework of modelling different LoDs of AC behavior can inspire researchers and modelers on understanding and determination of OB modeling LoDs for various future projects.

Design of a latent heat thermal energy storage system under simultaneous charging and discharging for solar domestic hot water applications

Latent heat thermal energy storage (LHTES) systems using phase change materials (PCMs) have appeared as promising solutions for energy storage when harnessing renewable energy sources in a wide range of engineering applications. The present study focuses on the design of horizontal shell-and-tube PCM-based LHTES systems capable of simultaneous charging and discharging in solar domestic hot water (SDHW) applications. Two scenarios are investigated: (i) initially fully charged, and (ii) initially fully discharged LHTES systems, in both cases with a 30-min charge/discharge time interval. Configurations with key geometrical design variations are considered to identify the best radial and tangential positions of the heat transfer fluid (HTF) tubes inside the shell that enhance storage performance against the following criteria: (i) gained and released thermal power, and (ii) total gained and released energy per unit mass of PCM. The distance between the hot and cold HTF tubes was maintained constant and an LHTES with horizontally aligned HTF tubes was selected as a baseline case. The findings showed that tangential displacement had a considerable impact on the performance of the system, while the effect of radial displacement was marginal. A design with displacements of ¼ tube diameter and 90° in the radial and tangential positions of the HTF tubes, respectively, had promising performance in both considered scenarios. In comparison to the baseline case, which had the hot and cold tubes positioned horizontally, and symmetrically on the shell's central plane, this configuration demonstrated a 103.02% enhancement in energy delivery in the fully discharged and a 2% enhancement in the fully charged scenario, respectively.

Temperature dependence of thermophysical properties of polyethylene glycol in solid/liquid phase change region

The knowledge of the thermophysical properties of phase change materials (PCMs) is of great importance in the design of thermal energy storage systems. In this work, several thermophysical properties of four PEGs with different molecular weights from 800 to 2000 were studied experimentally. Differential scanning calorimetry (DSC) was used to study the phase change temperatures and latent heat in the melting and crystallization processes of PEGs. The thermal conductivities of PEGs covering both solid and liquid phases were measured by a transient hot-wire thermometer at a temperature range from 283.15 to 353.15 K. Density and viscosity of liquid PEGs were determined by densimeter and viscometer, respectively. Phase change latent heat, thermal conductivity, and density increase with PEG molecular weight, which indicates that PEGs with higher molecular weight show better energy storage ability per volume. Phase change temperatures vary with molecular weight, so a wide range of operating temperatures can be satisfied using different molecular weight PEGs. Viscosity increases dramatically with PEGs molecular weight, so higher pump energy consumption is needed for larger PEG when it flows in the liquid phase. Furthermore, available literature data were used to compare with our results, our data agree well with most literature data.

Integrating 10-kV SiC MOSFET Into Battery Energy Storage System With a Scalable Converter-Based Self-Powered Gate Driver

In the hardware design of battery energy storage system (BESS) interface, in order to meet the high-voltage requirement of grid side, integrating 10-kV silicon-carbide (SiC) MOSFET into the interface could simplify the topology by reducing the component count. However, the conventional gate driver design is challenging and inextensible in BESS, since the high-voltage rating and high dv/dt bring the requirements of high-voltage isolation and low common-mode capacitance. Therefore, in this article, a scalable converter-based self-powered (SCS) gate driver is further proposed. A 5-kV input power extracting converter based on a voltage-balanced SiC MOSFET stack is constructed to self-power the gate driver, which exhibits simplification of basic topology and sufficient gate driver power handling capability regardless of the switching requirement of main loop power device. Besides this, the power extracting converter is designed to act as a clamping resistor-capacitor-diode (RCD) snubber circuit, which makes the SCS gate driver scalable to the series connection of power devices. Analysis and design consideration are given in detail, followed by the experimental verification using 10-kV/10-A SiC MOSFETs.

Development of a Method for Sizing a Hybrid Battery Energy Storage System for Application in AC Microgrid

This article addresses the development of the energy compensation method used for the design of hybrid energy storage systems—HBESS. The combination of two battery technologies offers better cost and performance when considering microgrid systems to provide uninterrupted power to sensitive loads (substation auxiliary system) and also provides greater energy security. In the event of a failure, the load needs to continue operating, and batteries such as lithium ions have a fast response, but are expensive for large-scale systems. However, some technologies offer low-cost and good availability of energy for long hours of discharge, such as lead–acid batteries. Consequently, different battery technologies can be used to meet all the needs of the sensitive loads. A specific method for sizing a HBESS was developed for islanded microgrids to support sensitive loads. This method was developed to meet the demand for substations outside the Brazilian standard of power systems that lack an uninterrupted and reliable energy source. The method is validated by designing a microgrid to support the auxiliary systems of a transmission substation in northeastern Brazil. The results showed a system with a capacity of 1215 kWh of lead-carbon and 242 kWh of lithium ions is necessary to maintain an islanded microgrid for at least 10 h. Furthermore, the microgrid comprises a PV plant with an AC output power of 700 kW in connected operation and 100 kW when islanded from the grid.

Machine learning for performance prediction in smart buildings: Photovoltaic self-consumption and life cycle cost optimization

The application of Photovoltaic (PV) system in buildings is growing rapidly in response to the need for clean energy sources and building decarbonization targets. Nonetheless, enhancing PV self-consumption through technical solutions such as Energy Storage Systems (ESS) is getting higher importance to increase the profitability of PV plants, by minimizing the building-grid interaction. In this context, analyzing PV self-consumption of different energy storage configurations becomes more relevant and crucial in building energy modeling although it is heavily time-consuming and complicated, particularly within a multi-objective optimization related to the ESS design. As a solution to resolve this issue, this paper evaluates the accuracy, training, and prediction speed of 24 Machine Learning (ML) models to be used as surrogate models for analyzing PV self-consumption in smart buildings. Furthermore, the performance of short-term Thermal Energy Storage (TES) to increase PV self-consumption is assessed and presented using ML models. The results showed the Gaussian Process Regression (GPR), Neural Networks (NN) including bilayered and trilayered NN models, Support Vector Machines (SVM) including the fine gaussian and cubic SVM models, and Ensembles of Trees (EoT) as superior ML models. The results also revealed that TES systems can efficiently increase PV self-consumption in the building equipped with electric heat pumps to provide heating, cooling, and domestic hot water. Moreover, the TES size optimization regarding the Life Cycle Cost (LCC) showed that the LCC-based optimum TES size can yield 7.1% savings within 30 years of the building service life. The novelties of this research are first to provide a reference to select the most suitable ML models in predicting PV self-consumption, second to implement machine learning for analyzing the performance of short-term thermal energy storage to enhance PV self-consumption in buildings, and third to carry out an LCC-based optimization on TES size using ML-based prediction models.

Special issue on “Optimal design and operation of energy systems”

Special issue on “Optimal design and operation of energy systems”

Design and Development of Hybrid Solar-Wind Energy Storage System for Storage Capacity

This research paper introduces a hybrid energy storage system using both wind energy and solar energy so that it can remarkably increase the energy storage capacity and the output power of the system. The proposed system is mainly used for storage purposes and the renewable energy sources are used instead of non-renewable energy source. Hybrid systems are considered an efficient research area in energy storage systems owning to their excellent output efficiency and better and excellent charge generation in case of any environmental conditions. It uses the conventional charging controller to charge the battery when wind and extreme solar irradiation conditions occur. The proposed project has started with MATLAB software simulation of the wind storage system and the solar energy storage system. After the Matlab Simulation, the prototype working model has been designed in an efficient manner with all the necessary components in both initial level prototype model and the final level prototype model. Then the working model is developed with the final model design. The results of the generated power from this hybrid energy storage system has been tested and verified by connecting the necessary details.

Composite Demand-Based Energy Storage Sizing for an Isolated Microgrid System

This paper presents a comprehensive model for optimal energy storage system (ESS) design for an isolated microgrid. The model presented is a mixed integer linear program (MILP) that considers seasonal varying generation (VG) demand, more specifically seasonal solar cell generator (SCG) demand, SCG maintenance (failure and restoration) rates, and practical operation of conventional generation (CG) while satisfying the required demand and reserve. The model is based on unit commitment (UC) to simulate real operations and physical constraints of CG units, the power balance, and reserve requirements. The objective function aims at minimizing the associated cost of CG, namely, production (fuel), costs of startup and shutdown procedures, and the investment cost of power and energy. The proposed model is assessed on a case study system consisting of multiple SCGs in addition to CG to meet a specific demand. The proposed model showed that the ESS sizing when considering Li-Ion technology and a SCG penetration of 25% was on average approximately 3 MWh and 1.70 MW. Meeting the demand and reserve requirements were the two major constraints when determining the optimal ESS sizing. Moreover, introducing the ESS substantially reduced the operating cost of the system.

A Novelty of Several Optimization Criteria Hybrid Energy Storage System and Power Management in EV Applications

The power management capabilities of hybrid energy storage systems offer several advantages for EVs, including improved performance, longer battery life, and reduced cost. HES technologies which combine Li-ion cells with ultra-capacitors (UC), are developing as just a possible alternative to the constraints of conventional ESS for conserving electricity. Lithium-ion batteries have a limited cycle life, meaning that they gradually degrade with each charge-discharge cycle. This can reduce the overall lifetime of the ESS and require more frequent replacements, adding to the cost and environmental impact of EVs. To circumvent those constraints, mixed battery packs combining battery technology as well as superconductors are being developed. To improve the design and control of hybrid energy storage systems for electric vehicles (EVs), a bi-level multi-objective framework has been proposed. A Bi-level multi-objective design and control framework, incorporating NSGA-II and fuzzy logic control, to obtain an optimal sized hybrid energy storage system and corresponding power management strategy. This dynamic and multi-objective architecture may achieve optimum solution hybrids battery bank as well as a matching significant power scheme one at a moment through integrating non-dominated sorting genetic and fuzzy logic control methods. To evaluate the effectiveness of the proposed bi-level multi-objective framework, Pareto optimal solutions of different hybrid energy storage systems are obtained. This approach can lead to significant improvements in the performance and efficiency of hybrid energy storage systems, making them more suitable for EVs and other applications that require high-performance energy storage solutions. Index Terms—Batteries, ultra capacitors, recursive imprecise input, non – linear and non optimisation, and e – mobility

Design of Thermal Energy Storage System

The paper concentrates on the design of a sensible thermal energy storage system. In a process plant, steam is used to create vacuum in a pressure vessel. Thereafter, steam is exhausted to the environment in a carbon steel pipe. A thermal energy storage system is designed to partially absorb the wasted energy and to store the energy in a tank. Dowtherm, a popular heat transfer fluid is chosen as the energy storage medium. A bolt-on heat exchanger is used to transfer heat from the steam pipe. The heating mechanism, and thermal energy storage is modelled using MATLAB. The basic energy storage system is designed by employing engineering standards, alternatives, and constraints.

Research on dimensionless structure size of coil heat exchanger in heat discharging process of molten salt single tank heat storage system

• Optimum dimensionless size of coil heat exchanger was studied by simulation. • The optimal size of heat exchanger appears under the combined action of vortex and molten salt flow rate. • When the dimensionless pitch L/d =4, the heat exchanger has the best heat discharging performance. • When the dimensionless pitch is the best, the optimal dimensionless diameter is 0.25. There has been an increasing attention on single-tank thermal energy storage, attracted by the low cost, high efficiency and compactness in the operation. However, the most researches on single-tank thermal energy storage focused on the way of heat discharging and the arrangement of heat exchangers. Few studies on the dimensionless size of heat exchanger, which is important for the design of single-tank thermal energy storage, were carried out. In order to obtain higher heat exchange efficiency and design criteria of coil heat exchanger, the optimal dimensionless size of heat exchanger is studied by numerical simulation. The results show that both the dimensionless pitch and the dimensionless pipe diameter of the coil heat exchanger have a great influence on the heat discharging performance when the air is used as the heating medium and the molten salt is used as the heat storage medium. With the change of dimensionless pitch, the heat discharging performance and the flow field of molten salt are affected. When the dimensionless pitch L / d = 4, the heat discharging power and heat release are the highest. At this time, the temperature and flow field of molten salt are evenly distributed, and no temperature stratification and vortex are formed. When the dimensionless pipe diameter is changed on the premise of the optimal dimensionless pitch, the heat discharging power increases first and then decreases with the increase of dimensionless pipe diameter. When the dimensionless pipe diameter d / a =0.25, the molten salt flow rate in the single tank is relatively large and no vortex hindering heat transfer, and the heat discharging performance is the best. Therefore, under the joint action of molten salt velocity and vortex, the optimal dimensionless pitch and pipe diameter appear. The research results provide a theoretical basis and an example for the design of single tank energy storage system.

Design and analysis of a cascade energy storage system based on LNG-LAES

Faced with increasingly serious energy and environmental problems, LNG and renewable energy have gradually entered the public eye and become the key to solving these problems. However, if the large amount of cold energy contained in LNG and the energy storage technology that regulates the volatility of renewable energy are not properly utilized, energy loss will result. In this study, by combining LNG cold energy cascade utilization and liquid air energy storage technology, a cascade energy storage system based on LNG-LAES is proposed. According to the different electricity demand of end users at different times, the system is divided into three operation modes and respectively The heat transfer, energy, exergy and other aspects were analyzed. The analysis results show that the LNG-LAES cascade energy storage system designed in this research has certain advantages in terms of energy efficiency, exergy efficiency and practical economy.