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Energy Storage Systems
Abstract
The main aim of this chapter is to provide a comprehensive study on the application of energy storage systems in renewable energy-based distributed generation (DG) systems. This chapter investigates the potential benefits of utilizing energy storage, integrated with DGs. Then, the available technologies for the energy storage such as the batteries, superconducting magnetic energy storage, flywheel, electrochemical capacitors, pumped storage power plant, compressed air energy storage, hydrogen storage, and other reported technologies in the literature will be studied. The important criteria in the selection of proper energy storage systems, including application, size, lifetime, response time, capital, maintenance costs, and other important aspects will be discussed. Furthermore, a comprehensive definition of the types of storage methods, different technologies, as well as the advantages and disadvantages of each system will be presented. The economic and technical implications of using these devices in different conditions will be studied using hybrid optimization for electric renewables (HOMER) software.
... SoC is the amount of charge remaining in the cell, or the ability to supply energy to the load, while SoH is a parameter characteristic of the cell's health. The two parameters SoC and SoH are defined by the following formulas (1) and (2) [4][5][6]. ...
... This approach is better since SoC reflects more accurately the remaining energy in the cell. However, this method requires estimating the SoC of cells since SoC cannot be measured directly [4,5]. Some works [9,11,13] have used regression curves to estimate the SoC of cells to reduce the computational burden when estimating SoC. ...
This article presents an active state-of-charge (SoC) balancing control method that considers the aging effect on the lithium-ion battery cells in a series connection implemented by a bidirectional CuK converter circuit. The purpose of balancing the SoC process for cells in the series ensures that, in all operating conditions, the current and temperature of the cells do not exceed the technical limits corresponding to the degree of aging of the cells. The nonlinear optimal control problem is established based on constraints on the balancing current, temperature, and the effect of cell aging in the dynamic model of the SoC balancing system. The sequential quadratic programming method is used to solve the optimization problem at sampling time to determine the optimal duty cycle of the pulse width modulation pulse to be applied to the balancing circuits. The SoC balancing results for cells are compared between the case where all cells in the series are new and the case where cells in the series have different levels of aging, showing differences in the control of balancing current and cell temperature in the SoC balancing process. The application of the optimal active SoC balancing method for cells in the series proposed in this article allows the cells in the series to operate safely, extend the life of the battery cells, and reduce costs for energy storage applications aimed at popularizing the use of renewable energy sources and promoting the development of the electric vehicle industry, accelerating the implementation of global carbon reduction and environmental protection.
... SoC is the amount of charge remaining in the cell, or the ability to supply energy to the load, while SoH is a parameter characteristic of the cell's health. The two parameters SoC and SoH are defined by the following formulas (1) and (2) [4], [5], [6]. ...
... This approach is better since SoC reflects more accurately the remaining energy in the cell. However, this method requires estimating the SoC of cells since SoC cannot be measured directly [4], [5]. Some works [9], [10], [12] have used regression curves to estimate the SoC of cells to reduce the computational burden when estimating SoC. ...
This article presents an active State-of-Charge (SoC) balancing control method that considers the aging effect on the Lithium-Ion battery cells in a series connection implemented by a bidirectional CuK converter circuit. The purpose of balancing the SoC process for cells in the series ensures that, in all operating conditions, the current and temperature of the cells do not exceed the technical limits corresponding to the degree of aging of the cells. The nonlinear optimal control problem is established based on constraints on the balancing current, temperature, and the effect of cell aging in the dynamic model of the SoC balancing system. The sequential quadratic programming (SQP) method is used to solve the optimization problem at sampling time to determine the optimal duty cycle of the pulse width modulation (PWM) pulse to be applied to the balancing circuits. The SoC balancing results for cells are compared between the case where all cells in the series are new and the case where cells in the series have different levels of aging, showing differences in the control of balancing current and cell temperature in the SoC balancing process. The application of the optimal active SoC balancing method for cells in the series proposed in this article allows the cells in the series to operate safely, extend the life of the battery cells, reduce costs for energy storage applications aimed at popularizing the use of renewable energy sources and promoting the development of the electric vehicle industry, accelerating the implementation of global carbon reduction and environmental protection.
... At 100%, the cell is considered fully charged, and at 0%, it is considered fully discharged. However, the threshold for a cell is practically 50% for it to be recharged [43]. It should be noted that a fully charged, aged battery may have a state of charge equivalent to 80%-70% of the state of charge of a new battery. ...
... It should be noted that a fully charged, aged battery may have a state of charge equivalent to 80%-70% of the state of charge of a new battery. The battery's state of charge may be affected as the battery becomes older [43]. Different kinds of methods have been proposed for determining the state of charge of a battery. ...
This study proposes a feedforward deep neural network to predict the parameters of the lithium-ion battery in electric vehicles. Correlation analysis is used to select the candidate parameters for the proposed model with no categorical variable. A direct feedforward deep artificial neural network is developed to predict a battery’s charge state and develop the proposed inverse model. The predicted state-of-charge of the direct model is combined with four virtual functions to form the input variables for the proposed inverse model. Furthermore, virtual functions are incorporated to enhance the predicting capability of the proposed inverse function model. The predicted multi-output variables of the proposed inverse model are speed, mileage, voltage, velocity, and state-of-charge. The proposed inverse model is superior to the feedforward deep neural network previously proposed in the literature because of its multiple output capabilities. Also, the proposed model makes decision-making easier when used for the design simulation than the single-output deep neural networks, which predict the state-of-charge of a battery only. The mean square error is used as the metric for accurate measurement. During the simulation by the proposed inverse model (with virtual functions), accuracy was 44.43 times higher than the traditional inverse deep neural network model. Redefined parameters were used to verify the findings of the model. This result suggests that incorporating virtual functions into a deep neural network model’s inverse model can improve the accuracy of battery and electric vehicle parameter predictions
... For better performance and longer battery life, the least SOC value should be 50 % [29]. Gate pulse d Q1 for switch Q 1 by considering the performance indicators can be understood from (12) to (14). ...
... In this proposed scheme, nine UC cells with a voltage of 2.7 V are used in a series fashion. The total capacity of the UC cell is shown in(29). ...
Energy management strategy (EMS) works as an exchange where the allotment of power is decided between different
sources in the hybrid energy storage system (HESS). While designing EMS, the performance indicators of the HESS,
like voltage and state-of-charge of sources, dc-link voltage, and battery power delivering rate, should be
considered for extended battery operation to enhance the vehicle performance effectively. The rate limiter
restricts the rate of power flow from the battery and thus protects the battery from a high current rate,
ensuring extended operation. This paper proposes a modified topology and EMS for controlling performance
indicators with rate limiter operation. The HESS consists of one battery and two ultracapacitor banks.
The auxiliary ultracapacitor is used to counter the effect of the rate limiter on vehicle dynamics.
The auxiliary battery with reserve capacity is considered to run the vehicle in an emergency condition.
This auxiliary battery storage is integrated with renewable (solar) as a standby provision.
The proposed schemes are capable of providing supervisory control over performance indicators.
It is evident from the simulation results that the proposed scheme saves 11.79% of battery
energy for a designed load torque as compared with a battery-alone electric vehicle.
... Other storage technologies also have some inherent limitations such as: low energy density, low efficiency, slow response time, relatively high production cost etc. which serves as constraints for their widespread adoption today [5], [6]. The comparison of power vs energy density for different energy storage systems is represented in Fig. 1. ...
... The electrolyte species circulate through each of the half-cell compartments of the porous carbon-felt electrodes by transport mechanisms such as diffusion, migration and convection [13]. The porosity of the electrode has a significant impact on electrode characteristics such as permeability, effective conductivity and effective diffusion coefficient of the electrolyte ion species [6]. Although carbon-felt electrode are low cost and well-suited for VRFB applications, its compressibility nature needs to be taken upon consideration to yield better results [14]. ...
As the demand of electric power generation has increased vastly across the world, the requirement of upgraded schemes for efficient power extraction and bulky storage has burgeoned tantamountly. To adopt the randomness and best uti-lization of the renewable energy sources, power profile prediction and energy management of large-scale solar and wind farms are major concerns for grid operators. A bulk efficient energy storage system may eliminate the issues related to unpredictability of sustainable power sources. Mostly conventional deep cycle lead-acid battery banks are utilized to meet massive storage requirement in solar and wind farms. However, the high cost, extensive maintenance, requirement of extra space and relatively short lifetime are the major shortcomings of lead-acid batteries. On the other hand, the development of Vanadium Redox-flow battery (VRFB) makes it possible to be utilized for large-scale storage because of its viable chemical composition, compact energy density and long lifecycle. In this paper, a multiphysics model of a 8 MW-h Vanadium redox-flow battery is developed for large-scale storage. The features of the VRFB have been analyzed for variation of its key parameters. To observe the effectiveness of the proposed model, a 3 MW grid-connected hybrid renewable power system consisting of photovoltaic (PV) panels and wind turbines is simulated with proposed storage unit. The battery framework is designed in COMSOL Multiphysics platform and dynamic simulations are performed in MATLAB/Simulink en-vironment. The results show that the proposed model exhibits compatible performance in managing the energy flow from the hybrid sources towards the load by maintaining the real power demanded by the grid operator.
... The BESS performs the function of mitigating the power supply variability between the load and generation (Gao, 2015a;Abdi, Mohammadi-ivatloo and Javadi, 2017;Alzahrani et al., 2017). The necessity for a BESS is vital for urban microgrid systems to provide power to loads during the island mode. ...
... The DC/DC converter topology adopted for urban microgrids is the buck-boost converter which plays the role of charging and discharging the BESS in the microgrid system as it allows bidirectional power flow (Gao, 2015b;Farrokhabadi et al., 2018;Kondrath, 2018). An ESS is capable of balancing power in a solar PV microgrid by working as the load or generator during the charging and discharging modes (Abdi, Mohammadi-ivatloo and Javadi, 2017). BESS models of solar PV microgrids exist in two ESS configurations namely aggregated and distributed ESS. ...
Solar Photo Voltaic (PV) powered community microgrids are a promising sustainable solution for neighborhoods, residential quarters, and cities in sub-Saharan Africa (SSA) to meet their energy demands locally and to increase energy independence and resilience. This review provides a comprehensive study on the nature of solar PV community microgrids. Through their capacity to operate in both grid-connected and island modes, community microgrids improve utility system resiliency while also boosting energy security in local states and towns. The integration of solar PV microgrids with the electricity utility grid requires control strategies to facilitate the load sharing between distributed generation units, voltage and frequency control, as well as emergency islanding. Control strategies such as hierarchical control and droop are discussed in the review article. To identify the effectiveness of control strategies through system simulation, a review of various modeling designs of individual components in a solar PV microgrid system is discussed. The article goes on to talk about energy optimization approaches and their economic impact on microgrid systems. Finally, the review concludes with an overview of the technical challenges encountered in the integration of solar PV systems in microgrids.
... SOC can be calculated by measuring the battery's voltage, current, or electrolyte condition. The SOC scale generally ranges from 0%, indicating the battery is completely empty, to 100%, indicating the battery is fully charged [16]. To predict the battery's SOC by calculating the current flowing into and out of the battery over time, the general formula for the Coulomb Counting approach is as shown in Equation below. ...
Solar panel, as a renewable energy source, require batteries to store the generated energy. Continuous use of batteries can l ead to capacity reduction and performance decline. To address this issue, it is important to have a system that can estimate the State of Charge (SOC) of the battery to control the charging process and maintain optimal battery performance. This research develo ps an SOC estimation system for lead-acid batteries by applying the Artificial Neural Network (ANN) algorithm. The ANN method has several advantages, such as more efficient iteration processes, increased speed in parameter updates, and the ability to achieve convergence more quickly. Meanwhile, the ANN algorithm also offers advantages in ease of implementation and better interpretability. The SOC estimation results for a 48V, 12Ah lead-acid battery using the ANN algorithm show that the training phase reveals a compelling regression plot, demonstrating an impressive R value of 0.99979. The minuscule error rate in the prediction system unequivocally affirms the exceptional quality of this ANN model.
... Energy performance is a key indicator of whether an energy storage system can efficiently and stably output electrical power. It affects both the energy utilization during charging and discharging and the overall efficiency of the system in grid-connected operations [35]. ...
Ports are critical hubs in the global supply chain, yet they face mounting challenges in achieving carbon neutrality. Port Integrated Multi-Energy Systems (PIMESs) offer a comprehensive solution by integrating renewable energy sources such as wind, photovoltaic (PV), hydrogen, and energy storage with traditional energy systems. This study examines the implementation of a real-word PIMES, showcasing its effectiveness in reducing energy consumption and emissions. The findings indicate that in 2024, the PIMES enabled a reduction of 1885 tons of CO2 emissions, with wind energy contributing 84% and PV 16% to the total decreases. The energy storage system achieved a charge–discharge efficiency of 99.15%, while the hydrogen production system demonstrated an efficiency of 63.34%, producing 503.87 Nm³/h of hydrogen. Despite these successes, challenges remain in optimizing renewable energy integration, expanding storage capacity, and advancing hydrogen technologies. This paper highlights practical strategies to enhance PIMESs’ performances, offering valuable insights for policymakers and port authorities aiming to balance energy efficiency and sustainability and providing a blueprint for carbon-neutral port development worldwide.
... The SOC data of a battery pack provided information regarding the available capacity in relation to the rated capacity. The SOC value can be expressed as a percentage, with 0% indicating that the pack is empty and 100% indicating that the pack is fully charged [73]. ...
The main objective of this paper is to present a methodology for the reliable estimation of the energy consumption of electric vehicles, focusing on the main electrical subsystems of passenger cars. This paper presents a comparative analysis of the available regression models and the results of our simulation experiments. While numerous regression models have been documented in the literature, their accuracy is not always satisfactory. Consequently, there is a need to develop a sufficiently accurate and comprehensive generalized simulation framework, which is presented in the paper. Currently, most of the major vehicle manufacturers have developed pure electric vehicle platforms and are using them in the production of many models available on the market. The estimation of consumption data for these vehicles is still based on traditional techniques, namely, prediction from historical operation data. To overcome this problem, in this article, we have constructed a multi-element, model-based simulation for the purpose of implementing an energy consumption monitoring system. In order to create a simulation that reflects real-life vehicle behavior, the input data are based on empirical measurements, while the simulation model is based on actual electric vehicle parameters. In the main simulation model, it is possible to simulate the energy consumption of the vehicle’s drive system and to extract the requisite input data for the simulation of the other vehicle subsystems. In regard to the simulation, the subsystems that have been incorporated are the electric vehicle steering system, the vehicle lighting system and the HVAC system. After running the simulation, the total system consumption for a given trip segment is obtained by running each vehicle subsystem simulation. The findings were validated with real data and compared with two relevant regression models. Our preliminary expectation is that, given the level of detail of our simulation, the developed model can be considered validated if the error of the estimate remains below 4% and if the simulation model in question yields superior results in comparison to other regression models.
... To ensure optimal performance and longevity of cells in practical applications, the lower range of SoC is limited to 50%. To reduce the stress on electrodes, the maximum SoC is capped at 90%, which also reduces heat generation during charging and slower the rate of capacity loss over time [43]. Depth of Discharge (DoD) is another parameter which describes the depth to which the battery is discharged and is calculated as (1 − SoC). ...
Accurate estimation of state of health (SoH) of the battery over long‐term is a critical challenge for the battery management systems in electric vehicles. This is due to the challenges in accurately modeling the accelerated aging and degradation phenomena caused by diverse operating conditions of the battery. This paper presents a cascaded recurrent neural networks (RNN) with long short‐term memory (LSTM) to estimate the internal resistance and SoH, taking account of various abnormal operating conditions of the battery. A datasheet‐based degradation model of the battery is developed using fade equations. The training and validation data set for LSTM‐RNN are generated by subjecting the battery model to various factors that cause accelerated degradation, such as fast charging, varying operating temperatures, overutilization, and cell imbalance. The cascaded LSTM‐RNN is trained to estimate SoH only once after the completion of every charge–discharge cycle. The training error index parameters of the proposed SoH estimator are well within 1%, demonstrating the reliability and robustness of the estimator to diverse operating conditions of the battery.
... The hourly electrical requirement for this greenhouse size that includes the water requirements is 990 W [103][104][105]. The greenhouse cover utilized in the design is transparent low-density polyethylene with the transmittance being 0.72 and other related details in Table 6. ...
Qatar identified that food supply security, including self-sufficiency in vegetable production and increasing sustainable renewable energy generation, is important for increasing economic and environmental resiliency. Very favorable solar energy resources in Qatar suggest opportunities to simultaneously meet this goal by integrating solar energy generation and food production. This study examines the feasibility of developing a sustainable agri-photovoltaic (APV) greenhouse design. A comprehensive greenhouse with solar energy generation included is developed for year-round operation in Lusail, Qatar. The performance of the system is predicted by integrating meteorological data and MATLAB simulations of system components. Important design considerations included optimizing solar energy generation by fixed solar photovoltaic panels placed on the maximum available surface area of the greenhouse canopy, while balancing crop insolation and energy needs for greenhouse HVAC systems. Electrical energy is also stored in an industrial battery. Results suggest the APV greenhouse is technically and economically viable and that it could provide benefits, including enhancing food security, promoting renewable energy, and contributing to sustainable food and energy production in Qatar.
... In this study, the VIC was applied with Supercapacitor Energy Storage (SCES). SCES outperforms batteries due to its superior power density, high efficiency, rapid charge/discharge, and extended lifetime [8], [9]. These characteristics make SCES suitable for providing response to frequency stability [10] and inertia emulation [11]. ...
... In practical applications, the SOC is not allowed to exceed 50%, so the cell is recharged when the SOC reaches 50% [22]. SOC is a key parameter for the correct control of an electric vehicle. ...
The aim of this review was to provide a comprehensive assessment of the global development and sustainability of lithium-ion batteries (LIBs) for electric vehicles. Production of various renewable energy sources has proven to be sustainable; however, with certain types of renewable energy sources, due to the cyclical nature of natural resources, energy production is not constant, and energy production needs to be more balanced with consumption needs. In the future, this problem could be alleviated if global energy storage capacity were improved and expanded. Today, batteries are an important but underutilized energy source for electric cars. LIBs have a long history behind them and currently play the most crucial role in the electric car industry. LIBs are primarily characterized by high energy and power density, which makes them incomparably competitive for use in electric cars. The research presents and processes in detail segments related to the development, principle of operation, and sustainability of LIBs, as well as the global manufacturing capacity of LIBs for electric vehicles.
... SoC is an estimation of the amount of energy left in a cell or battery; which can be described as the quantity of electrical charge contained in the cell or the battery at any time t in relation to the nominal electrical charge [1,2]. SoC can be one of the significant features of lithium-ion cells for efficient and secure use in different fields such as control of photovoltaic-wind-battery systems [3,4], Electrical vehicles [5][6][7], microgrid energy management [8][9][10] and numerous other applications. ...
Numerous approaches and methodologies have been established for online (while the load is supplied) estimation of the State-of-Charge of Lithium-ion cells and batteries. However, as battery load consumption fluctuates in real time because of delivered device operations, obtaining a precise online state of charge estimation remains a challenging task. This work proposes a new technique for online open circuit voltage measurement to estimate state of charge of batteries. This novel technique proposes the addition of an auxiliary regulated load that may be utilized to temporarily force specifically defined forms of the battery's current curve under particular conditions, which results in improving and simplifying online open circuit voltage computations. The effectiveness of the proposed technique was successfully validated through several experimental tests. The acquired findings demonstrated its efficiency with an acceptable online state of charge estimation accuracy. Typically, an estimation error of less than 2% was recorded in most tests, while the error was less than 1% when the battery’s state of charge was high.
... Subsequently, it should be remembered that each type of BESS has certain technical specifications that characterize the efficiency of the system [15]. It is clear that the first characteristic parameter is the storage capacity, i.e., the amount of electric charge that the battery can accumulate and that the BESS can make available. ...
With the growing push toward decarbonization of the electricity generation sector, more attention is paid to storage systems that can assist renewable energy sources (RES). Due to their variability, intermittent RES (such as wind or solar radiation) do not allow a power production distributed uniformly over the short term up to the mid- and long term. Storage of renewable electricity can significantly contribute to mitigate these issues, enhancing power system reliability and, thus, RES penetration. Among energy storage technologies, the potential applications of battery are discussed in this chapter. Focus is placed on applications related to battery energy systems integration in both power systems and electric transportation means.
For grid integration, bulk energy services, transmission and distribution network support, and capacity firming coupled to highly variable RES plants are addressed. Regarding transportation applications, electric mobility and perspectives on the interaction of electric vehicles (EVs) with the electric infrastructure are presented and discussed. Finally, this chapter addresses issues related to EVs’ battery aging and their dismission and exploitation as second life batteries in stationary applications.
... Energy storage is one of the emerging technologies which can store energy and deliver it upon meeting the energy demand of the load system. Presently, there are a few notable energy storage devices such as lithium-ion (Li-ion), Lead-acid (PbSO4), flywheel and super capacitor which are commercially available in the market [9,10]. With the recent advancement and market value of energy storage, the potential of this technology is more significant towards the integration of the power system network due to the large amount of renewable energy source (RES) deployed in the future. ...
... Among several different types of ESSs being used, battery energy storage system (BESS) is one of the most widely used ESS, especially for DERs managements. In practice, ESS can be used to reduce the electrical system peak demand and power loss [2]. Moreover, when considering how to implement the widespread integration of renewable energy resources (RERs), the application of ESS is essential [3]. Figure 1 explains that the system demand can be handled efficiently if storage is incorporated into the electrical network. ...
... State of Charge (SOC): SOC is defined as the ratio of the currently available charge in a battery as a function of its rated capacity, as shown in equation (1) [37]. ...
... Consequently, electricity storage should enable a significant increase Electrochemical capacitor in aqueous electrolyte with long lifespan improved by hydrogen bond donor addition in the market for renewable energy production in power grids. In fact, the charge storage has always been a major weakness of the energy cycle [1]. Several energy storage systems are available. ...
In the electrochemical capacitors (ECs) operating with aqueous electrolytes, corrosion of the current collector is one of critical issues that affects the cycling life, efficiency, and capacitance of the devices. So far, there are no stable metal current collectors in the water-based electrolyte because of its corrosive nature, even if the pH is close to neutral. Here, urea (CH 4 N 2 O) is used as an anticorrosive, green additive to 1 M lithium sulfate electrolyte for low-cost electrochemical capacitors based on carbon BP2000 electrodes. In this work, the corrosion study of stainless steel in the presence of such amide demonstrates an effective corrosion-inhibiting character owing to the urea interaction with water in the hydrogen-bonded network. Chemical stability of current collectors owing to a significant 10-fold decrease of the corrosion current and shift of the corrosion potential into negative side has been achieved when 2 M urea, i.e., hydrogen-bond donor (HBD) is added to electrolyte. Furthermore, the addition of this organic compound improves the capacitive performance of the system and prevents the fading of the device with no influence on the electrolyte conductivity. During the floating test of EC at 1.6 V operating in 1 M Li 2 SO 4 with 2 M urea, the capacitance and resistance values keep the end-of-life criteria for over 350 h. Moreover, the galvanostatic investigation of such EC (at 1 A/g) displays performance of more than 60 000 cycles. Furthermore, operando experiments proved that carbon-based electrodes behave differently in lithium sulfate with urea and without additive owing to the formation of strong hydrogen bond network. The molecular structure of electrolyte has been estimated by DFT calculations. Overall, by using lithium sulfate and urea as an electrolytic system, the EC current collector has not only superior corrosion resistance against the aqueous electrolyte but also a high anti-ageing character at 1.6 V, which is favorable to improve the EC electrochemical performance. The use of urea as a stable, cheap electrolyte additive provides an innovative technique to enhance the performance of low-cost aqueous based supercapacitors.
... In addition, to keep the battery from getting worse during V2G operation, think about the minimum state of charge (SOC) for charging and the minimum SOC for discharging [13]. This will limit the impact on the grid. ...
... SOH refers to the instantaneous parameters of the battery and how they relate to the full health parameters of that battery; usually represented as a percentage, this value represents the degree of ageing of a battery, represented in capacity loss or resistance increment [37]. SOC represents the remaining charge of the battery; there are many methods used to determine this value (coulomb counting, OCV [38], neural network [39,40], Kalman filter [41][42][43][44][45], etc.) [46]. RUL uses the SOH to estimate the operation of the battery until it reaches the 20% drop in overall capacity and thus needs to be replaced [47]. ...
Energy storage devices are fast becoming a necessity when considering a renewable energy harvesting system. This improves the intermittency of the source as well as significantly increasing the harvesting capacity of the system. However, most energy storage devices have a large limitation with regards to their usable life—this aspect is especially relevant to batteries. The degradation of batteries (and energy storage devices) plays a large role in determining their feasibility and the degradation is determined through capacity estimations—due to the inability/difficulty of directly measuring instantaneous capacity. This article aims to research the various methods used to estimate the capacity as well as the applications of these measurements aimed at reducing the degradation of the energy storage device. Through this research, the advantages and disadvantages of the measurements and their applications will be revealed, which will then highlight an area in which these estimations or their applications can be improved. The novelty of this paper lies in the graphical representation of the capacity measurement techniques, and how they relate to each other, as well as the relations and differences between their applications, highlighting the limitations in how the measurements are used.
... The flywheel is a heavy rotating disk used to store angular momentum. This equipment resists changes in rotational speed, and when an irregular torque is applied to it, it tries to stabilize the rotation axis [119]. Barelli The concept of storing energy based on gravity relies on the lifting of a heavy mass to store energy in the form of potential energy. ...
Excess electricity, surplus power, or dumped energy refers to the unused portion of energy in hybrid renewable energy systems (HRESs), which can significantly impact the stability, affordability, and reliability of the energy system. Surplus power is often generated due to the intermittent nature of renewable energy resources when battery is fully charged or the generator's minimum output exceeds the load. While it can be transferred to the grid utility in grid-connected HRESs, off-grid systems face a significant challenge with high amounts of excess power. Therefore, surplus electricity is a crucial factor that affects the development of stand-alone HRESs. This review study aims to identify and classify prevalent and practical methods for reducing excess electricity in stand-alone HRESs based on the performance concepts in excess power reduction. Accordingly, four categories of excess electricity direct use, storage of excess electricity, indirect use of excess electricity, and decrease of excess electricity production are introduced. Finally, deferrable load, power to heat, storage banks, power to hydrogen, power to gas cycles, multiple generators, and loss of power supply were detected as the most prevalent methods. These methods were discussed based on their impacts on energy cost, renewable fraction, and excess electricity reduction potential in HRESs.
••••• Highlights:
• Practical solutions for excess electricity reduction in off-grid units are reviewed.
• Effective methods and technologies are classified based on performance concepts.
• The excess electricity of efficient stand-alone hybrid systems must be less than 10% (ideally <5%).
• A comparison based on energy cost, renewable fraction & excess potential is provided.
• The worldwide practical constraints in surplus power management are highlighted.
... The concept of energy storage is elaborated, concerning a wide range of technologies, locations, capacities, demands, and costs of investment. [2]. Energy Storage Modelling and Settlements was initiated by Public Utility Commissions in US with [3], considering multiple types of storage technologies as batteries, flywheels, compressed air energy storage, pumped storage, electrochemical capacitors, and thermal energy storage. ...
During the last decades, battery energy storage systems (BESS) have received a growing interest due to appearance of applications supporting the stabilization of the power grid and improving both the performance and revenues for renewable energy sources, such as photovoltaic (PV), concentrated thermal solar (CSP) and wind plants. The report aims to highlight engineering considerations on BESS technologies design for grid support applications, to more efficient use of renewable energy plants in the context of current and future considerations related to global economy and deep decarbonisation of the grids.
... State of charge (SoC) refers to the existing charge of a battery relative to the rated capacity and is expressed in terms of percentage [10]. SoC estimation does not only give the status of the available energy but is also useful in identifying battery lifespan [11]. ...
Lithium iron phosphate (LiFePO 4 ) has become the top choice battery chemical in photovoltaic (PV) system nowadays due to numerous advantages as compared to lead acid batteries. However, LiFePO 4 needs a battery management system to optimize energy utilization. State of charge (SoC), state of health (SoH), cell balancing, remaining useful life are some of its crucial parameters. This review paper discusses overview of battery management system (BMS) functions, LiFePO 4 characteristics, key issues, estimation techniques, main features, and drawbacks of using this battery type.
... To materialize these projections and expectations regarding the global warming pathway of 1.5 °C above the preindustrial levels, it is essential to overcome the challenges associated with renewables, challenges like long distances between production and consumption sites, weather, and climate-dependent daily and seasonal fluctuations, and efficiency. An energy storage system (ESS) is considered a solution against the changeability and controllability of output power from renewables [4]. According to the CNESA [5] statistics report for 2020, the global operational ESSs capacity has increased by 3.4% compared to 2019 to a total capacity of 191.1 GW. ...
As an energy vector, hydrogen faces bulk storage and transportation challenges due to its low volumetric energy density. Following the footsteps of liquefied natural gas, hydrogen is also liquefied prior to transportation. Liquid nitrogen is usually used as the refrigerant in the precooling cycle; however, alternate candidates are also being studied. Liquid air, which is already drawing attention as a standalone cryogenic energy storage system, is one such candidate as enormous cold energy is available in its regasification phase or the discharge half-cycle. In the present study, liquid air is considered the refrigerant stream in the precooling section of the hydrogen liquefaction process. A well-known commercial simulator Aspen HYSYS® v12.1 is used for this unique concept's design and performance analysis. Composite curves analysis is performed to analyze the proposed integrated scheme's performance graphically. The specific energy consumption of 8.52 kWh/kg LH2 has been obtained in the unoptimized base case.
... High SGED ratios in various scenarios, combinations and seasons indicate that if appropriate sizing of battery bank can be done and the electrical vulnerability of the NU combinations can be eliminated during the disaster or energy outage scenarios. In the practical applications, the minimum recommended state of charge (SoC) for the battery bank is 50% [32] (minimum discharge limit for the battery) that can be accommodated easily with these high SGED ratios. By referring this minimum SoC number, it can be assumed that the minimum desirable value of SGED ratio is 2. For example, if electrical deficit is 100 kWh and surplus generation is 200 kWh (SGED ratio = 2), then 200 kWh surplus electricity can be stored in the battery bank and 100 kWh of which can be used maintaining 50% SoC of the battery bank. ...
The work proposes a technique to improve the infrastructure and energy resilience of new developments during the planning stage. Several resilience-related parameters are developed in this paper that can be used to quantify resilience. To apply these parameters, the work assumes various energy outage scenarios varying from less than 24 h to 3 weeks. During these scenarios, a neighborhood population can be relocated to several public buildings promoting better utilization of onsite energy resources. The technique is applied to four representative neighborhoods encompassing various sustainability measures including clean energy. Further, this paper demonstrates an urban scale improvement technique for greater energy and infrastructure resilience. The results indicate a significant improvement in infrastructure resilience by relocating public shelter buildings on the main street intersections so that these can be easily accessible during energy outages or disaster events. Energy resilience can be achieved by the appropriate design of onsite energy resources to eliminate vulnerabilities. For instance, 8.8% to 15.4% of additional land for solar thermal collectors can eliminate thermal energy vulnerabilities. When surplus generation from onsite resources is twice or more as compared to demand during their unavailability, the electrical vulnerability can be eliminated by employing suitable battery banks in various buildings.
Power system is a vast and complex network designed to generate, transmit and distribute electrical power to consumers effectively and reliably. Due to integration of renewable energy sources (RESs) and increase in non-linear load connections, power quality (PQ) problems are occurring in power system. This review paper presents an extensive analysis for classification of power quality issues (PQIs) using Fourier Transforms (FT), Discrete Fourier Transforms (DFT), Short Time Fourier Transforms (STFT), Fast Fourier Transforms (FFT), and Wavelet Transforms (WT) in modern electrical systems. This paper emphasizes the importance of fourier functions, notch filters and flexible AC transmission systems(FACTS).
Redox flow batteries (RFBs) are known for their exceptional attributes, including remarkable energy efficiency of up to 80%, an extended lifespan, safe operation, low environmental contamination concerns, sustainable recyclability, and easy scalability. One of their standout characteristics is the separation of electrolytes into two distinct tanks, isolating them from the electrochemical stack. This unique design allows for the separate design of energy capacity and power, offering a significantly higher level of adaptability and modularity compared to traditional technologies like lithium batteries. RFBs are also an improved technology for storing renewable energy in small or remote communities, benefiting from larger storage capacity, lower maintenance requirements, longer life, and more flexibility in scaling the battery system. However, flow batteries also have disadvantages compared to other energy storage technologies, including a lower energy density and the potential use of expensive or scarce materials. Despite these limitations, the potential benefits of flow batteries in terms of scalability, long cycle life, and cost effectiveness make them a key strategic technology for progressing to net zero. Specifically, in Australia, RFBs are good candidates for storing the increasingly large amount of energy generated from green sources such as photovoltaic panels and wind turbines. Additionally, the geographical distribution of the population around Australia makes large central energy storage economically and logistically difficult, but RFBs can offer a more locally tailored approach to overcome this. This review examines the status of RFBs and the viability of this technology for use in Australia.
In the last few years, the use of domestic renewable energy solutions has increased, leading to a more widespread use of electrochemical energy storage systems due to their unpredictable nature. Lead acid cells are still the most employed kind of cells in this field. However, lithium-ion cells are considered the most promising approach, and their use is increasing considerably. In this context, we have developed an automated system for characterizing lithium-ion cells, able to reproduce any protocol the cells are subjected to during real applications with renewable energy solutions. Here, we focused on the uncertainty study, particularly determining the relative difference in the measurement of the most critical parameters involved in charging and discharging cycles and the combined uncertainty associated with the measurement of capacity, energy, and energy density. Unlike previous studies, we assess repeatability uncertainty by testing two cells with very different chemistry compositions: one more suitable for renewable energy solutions usage, the lithium iron phosphate – LFP cell, and one more indicated for automotive applications, the polymer ion lithium – POLI cell, performing three consecutive repetitions for each battery. The combined uncertainty was then calculated by combining the repeatability uncertainty with the instrumentation one. After that, we reproduced a 24-hour real scenario of a home solar-based storage system integrated with the grid. We reported an accurate discrimination in the transition between the constant current (CC) and constant voltage (CV) charge phases, and the correct interruption during the CV charge and the CC discharge cycles. In addition, the system accurately measures the capacity and energy with combined uncertainties generally lower than 2.4 %, regardless of battery type. This study makes an important contribution to the battery energy storage field by providing a combined study between the uncertainties analysis and a practical implementation of lithium-ion cells for real conditions related to renewable energy systems.
Nanoscale semiconductor particles known as quantum dots have distinct electrical and optical characteristics. Quantum dots (QDs) show remarkable promise in the solar energy arena for enhancing solar cell performance. Their adjustable bandgap maximizes the use of the solar spectrum and raises the overall efficiency of energy conversion. As they provide adjustable emission colours, QDs are also essential to the advancement of energy-efficient light-emitting diodes (LEDs). QDs also improve thermoelectric materials, which makes it possible to convert waste heat into energy more effectively. In order to increase charge/discharge rates, energy density, and cycle life overall, quantum dots are being investigated for use in batteries and capacitors. The potential of quantum dots in supercapacitors is also examined in this article. Furthermore, their integration into smart windows offers a creative way to control interior temperatures and lessen the need for artificial lighting, which supports the construction of energy-efficient buildings.
A cloud computing-based power optimization system (CC-POS) is an important enabler for hybrid renewable-based power systems with higher output, optimal solutions to extend battery storage life, and remotely flexible power distribution control. Recent advancements in cloud computing have begun to deliver critical insights, resulting in adaptive-based control of storage systems with improved performance. This study aims to review the recently published literature on the topic of power management systems and battery charging control. The role of intelligent based cloud computing is to improve the battery life and manage the battery state of charge (SoC). To achieve this purpose, publishers' databases and search engines were used to obtain the studies reviewed in this paper. We identify and review the purpose, achievements, tools/algorithm, and recommendations for each survey work, and thus outline a number of key findings and future directions. Furthermore, the review includes a listing of novels and recently used algorithms. Additionally, a critical review of 174 research articles were analyzed as per Web of Science (WoS) and Scopus database. The key findings of this study are discussed in two key conceptual frameworks that contain a power optimization system and an optimal battery management system. The power transmission, distribution, and charge and discharge processes are controlled and stored on cloud computing using the power mix between hybrid renewable energy and other power sources.
The energy storage systems (ESSs) are widely used to store energy whenever the grid is operating with surplus power and deliver the stored energy at the time grid is operating at deficient power. Pumped hydroelectric power plants are traditionally used as energy storage systems in the power systems. It pumps the water from the lower basin to the upper basin during the nonpeak hours at a reduced cost of electricity and discharges it during the peak hours at a higher cost and maintains the grid stability. Due to recent technological developments in renewable energy sources, solar photovoltaic (PV) systems and wind energy conversion systems are widely used for power generation. The main disadvantages of these renewable energy sources are intermittent output power from them, i.e. power output from these renewable energy sources is extremely irregular (non‐uniform) and varies based on climatic and environmental constraints/factors. The ESS plays a vital role in the large‐scale integration or penetration of renewable energy sources into the power system and in improving system stability. Whenever the output power from these renewable power plants is higher than the load demand, the ESS is used to store the surplus available energy into it and discharge it whenever the output power from the renewable power plants is lesser than the load demand. In addition to it, ESS also provides ancillary services like peak shaving, load shifting, power quality enhancement, etc. This chapter discusses the need for energy storage systems in different segments of power systems.
Energy storage systems are becoming increasingly important, with a growing focus on renewable energy sources that provide highly uctuating output. erefore, sound decisions regarding the energy storage systems to be employed need to be made, especially with a systematic and semantic approach. is paper considers the problem of evaluation and selection of energy storage technologies (ESTs). e objective of the proposed research is to decide the best technology for energy storage under the novel idea of hybrid multicriteria decision-making technique under fuzzy environment, that is, fuzzy AHP with fuzzy VIKOR. Electro-chemical storage, electrical storage, magnetic storage, mechanical storage, and chemical storage are considered as ve alternative energy storage technologies. Energy density, life cycles, cycle e ciency, investment level, suitability to climatic conditions, and required space are considered as six main evaluation criteria. Under each of the main criteria, a set of subcriteria are also considered. e weights of main criteria and subcriteria are determined using fuzzy AHP. With the help of the weights of each set of subcriteria, the weights of alternatives are determined using fuzzy VIKOR. Further, with the help of the main criteria weights and the weights of alternatives determined with respect to each set of subcriteria, the nal normalized weights of alternatives are determined. Based on these weights, energy storage technologies are ranked. In addition, the sensitivity analysis is carried out to analyze the variation in ranking pattern of alternatives. From the research ndings of this paper, the results are found to be more practical as the evaluation is carried out on an objective basis.
As renewable energy sources, such as solar systems, are becoming more popular, the focus is moving into more effective utilization of these energy sources and harvesting more energy for intermittency reduction in this renewable source. This is opening up a market for methods of energy storage and increasing interest in batteries, as they are, as it stands, the foremost energy storage device available to suit a wide range of requirements. This interest has brought to light the downfalls of batteries and resultantly made room for the investigation of ultra-capacitors as a solution to these downfalls. One of these downfalls is related to the decrease in capacity, and temperamentality thereof, of a battery when not used precisely as stated by the supplier. The usable capacity is reliant on the complete discharge/charge cycles the battery can undergo before a 20% degradation in its specified capacity is observed. This article aims to investigate what causes this degradation, what aggravates it and how the degradation affects the usage of the battery. This investigation will lead to the identification of a gap in which this degradation can be decreased, prolonging the usage and increasing the feasibility of the energy storage devices.
In recent years, several factors such as environmental pollution which is caused by fossil fuels and various diseases caused by them from one hand and concerns about the dwindling fossil fuels and price fluctuation of the products and resulting effects of these fluctuations in the economy from other hand has led most countries to seek alternative energy sources for fossil fuel supplies. Such a way that in 2006, about 18% of the consumed energy of the world is obtained through renewable energies. Iran is among the countries that are geographically located in hot and dry areas and has the most sun exposure in different months of the year. Except in the coasts of Caspian Sea, the percentage of sunny days throughout the year is between 63 to 98 percent in Iran. On the other hand, there are dispersed and remote areas and loads far from national grid which is impossible to provide electrical energy for them through transmission from national grid, therefore, for such cases the renewable energy technologies could be used to solve the problem and provide the energy. In this paper, technical and economic feasibility for the use of renewable energies for independent systems of the grid for a dispersed load in the area on the outskirts of Isfahan (Sepahan) with the maximum energy consumption of 3Kwh in a day is studied and presented. In addition, the HOMER simulation software is used as the optimization tool. ꀉ 2015 Institute of Advanced Engineering and Science. All rights reserved.
The development of battery electric vehicles (BEV) must continue since this can lead us towards a zero
emission transport system. There has been an advent of the production BEVs in recent years; however their low range and high
cost still remain the two important drawbacks. The battery is the element which strongly affects the cost and range of the BEV.
The batteries offer either high specific power or high specific energy but not both. To provide the BEVs with the characteristic
to compete with conventional vehicles it is beneficial to hybridize the energy storage combining a high energy battery with a
high power source. This shields the battery from peak currents and improves its capacity and life. There are various devices
which could qualify as a secondary storage system for the BEV such as high power battery, supercapacitor and high speed
flywheel (FW). This paper aims to review a specific type of hybridisation of energy storage which combines batteries and high
speed flywheels. The flywheel has been used as a secondary energy system in BEVs from the early 1970s when the oil crises
triggered an interest in BEVs. Since the last decade the interest in flywheels has strengthened and their application in the
kinetic energy recovery system (KERS) in Formula 1 has further bolstered the case for flywheels. With a number of
automotive manufacturers getting involved in developing flywheels for road applications, the authors believe commercial
flywheel based powertrains are likely to be seen in the near future. It is hence timely to produce a review of research and
development in the area of flywheel assisted BEVs.
Dispersed storage systems (DSSs) can represent an important near-term solution for supporting the operation and control of active distribution networks (ADNs). Indeed, they have the capability to support ADNs by providing ancillary services in addition to energy balance capabilities. Within this context, this paper focuses on the optimal allocation of DSSs in ADNs by defining a multi-objective optimization problem aiming at finding the optimal trade-off between technical and economical goals. In particular, the proposed procedure accounts for: 1) network voltage deviations; 2) feeders/lines congestions; 3) network losses; 4) cost of supplying loads (from external grid or local producers) together with the cost of DSS investment/maintenance; 5) load curtailment; and 6) stochasticity of loads and renewables productions. The DSSs are suitably modeled to consider their ability to support the network by both active and reactive powers. A convex formulation of ac optimal power flow problem is used to define a mixed integer second-order cone programming problem to optimally site and size the DSSs in the network. A test case referring to IEEE 34 bus distribution test feeder is used to demonstrate and discuss the effectiveness of the proposed methodology.
Lithium-sulphur batteries are one very appealing power source with high energy density. But their practical use is still hindered by several issues including short lifespan, low efficiency and safety concern from the lithium anode. Polysulphide dissolution and insulating nature of sulphur are generally considered responsible for the capacity degradation. However, the detachment of discharge products, that is, highly polar lithium sulphides, from nonpolar carbon matrix (for example, graphene) has been rarely studied as one critical factor. Here we report the strongly covalent stabilization of sulphur and its discharge products on amino-functionalized reduced graphene oxide that enables stable capacity retention of 80% for 350 cycles with high capacities and excellent high-rate response up to 4 C. The present study demonstrates a feasible and effective strategy to solve the long-term cycling difficulty for lithium-sulphur batteries and also helps to understand the capacity decay mechanism involved.
A unified energy exchange system with an equivalent dc circuit topology is presented for superconducting magnetic energy storage (SMES) study. The principle and experimental prototype design have been carried out to study the dynamic energy exchange characteristics of SMES for both voltage sag and swell compensations, with a new bridge-type I/V chopper and relevant digital control method introduced and compared with the conventional chopper. The bridge-type I/V chopper has been demonstrated to be more suitable for low-voltage power applications because of its high energy storage and exchange efficiencies. The integrated SMES application solutions and characteristics in the modern power systems have also been discussed using two sample cases of daily load leveling and voltage fluctuation compensation presented.
DC power systems are gaining an increasing interest in renewable energy applications because of the good matching with dc output type sources such as photovoltaic (PV) systems and secondary batteries. In this paper, several distributed generators (DGs) have been merged together with a pair of batteries and loads to form an autonomous dc microgrid (MG). To overcome the control challenge associated with coordination of multiple batteries within one stand-alone MG, a double-layer hierarchical control strategy was proposed. 1) The unit-level primary control layer was established by an adaptive voltage-droop method aimed to regulate the common bus voltage and to sustain the states of charge (SOCs) of batteries close to each other during moderate replenishment. The control of every unit was expanded with unit-specific algorithm, i.e., finish-of-charging for batteries and maximum power-point tracking (MPPT) for renewable energy sources, with which a smooth online overlap was designed and 2) the supervisory control layer was designed to use the low-bandwidth communication interface between the central controller and sources in order to collect data needed for adaptive calculation of virtual resistances (VRs) as well as transit criteria for changing unit-level operating modes. A small-signal stability for the whole range of VRs. The performance of developed control was assessed through experimental results.
As the fraction of electricity generation from intermittent renewable sources-such as solar or wind-grows, the ability to store large amounts of electrical energy is of increasing importance. Solid-electrode batteries maintain discharge at peak power for far too short a time to fully regulate wind or solar power output. In contrast, flow batteries can independently scale the power (electrode area) and energy (arbitrarily large storage volume) components of the system by maintaining all of the electro-active species in fluid form. Wide-scale utilization of flow batteries is, however, limited by the abundance and cost of these materials, particularly those using redox-active metals and precious-metal electrocatalysts. Here we describe a class of energy storage materials that exploits the favourable chemical and electrochemical properties of a family of molecules known as quinones. The example we demonstrate is a metal-free flow battery based on the redox chemistry of 9,10-anthraquinone-2,7-disulphonic acid (AQDS). AQDS undergoes extremely rapid and reversible two-electron two-proton reduction on a glassy carbon electrode in sulphuric acid. An aqueous flow battery with inexpensive carbon electrodes, combining the quinone/hydroquinone couple with the Br2/Br(-) redox couple, yields a peak galvanic power density exceeding 0.6 W cm(-2) at 1.3 A cm(-2). Cycling of this quinone-bromide flow battery showed >99 per cent storage capacity retention per cycle. The organic anthraquinone species can be synthesized from inexpensive commodity chemicals. This organic approach permits tuning of important properties such as the reduction potential and solubility by adding functional groups: for example, we demonstrate that the addition of two hydroxy groups to AQDS increases the open circuit potential of the cell by 11% and we describe a pathway for further increases in cell voltage. The use of π-aromatic redox-active organic molecules instead of redox-active metals represents a new and promising direction for realizing massive electrical energy storage at greatly reduced cost.
With the rapid growth of wind energy development and increasing wind power penetration level, it will be a big challenge to operate the power system with high wind power penetration securely and reliably due to the inherent variability and uncertainty of wind power. With the flexible charging-discharging characteristics, Energy Storage System (ESS) is considered as an effective tool to enhance the flexibility and controllability not only of a specific wind farm, but also of the entire grid. This paper reviews the state of the art of the ESS technologies for wind power integration support from different aspects. Firstly, the modern ESS technologies and their potential applications for wind power integration support are introduced. Secondly, the planning problem in relation to the ESS application for wind power integration is reviewed, including the selection of the ESS type, and the optimal sizing and siting of the ESS. Finally, the proposed operation and control strategies of the ESS for different application purposes in relation to the wind power integration support are summarized. The conclusion is drawn in the end.
Supercapacitor, known as an important energy storage device, is also a critical component for next generation of hydrogen fuel cell vehicles. In this study, we report a novel route for synthesis of three-dimensional Ni(OH)(2)/graphene/nickel foam electrode by electrochemical depositing Ni(OH)(2) nanoflakes on graphene network grown on nickel foam current collector and explore its applications in supercapacitors. The resulting binder-free Ni(OH)(2)/graphene/nickel foam electrode exhibits excellent supercapacitor performance with a specific capacitance of 2161 F/g at a current density of 3 A/g. Even as the current density reaches up to 60 A/g, it still remains a high capacitance of 1520 F/g, which is much higher than that of Ni(OH)(2)/nickel foam electrode. The enhanced rate capability performance of Ni(OH)(2)/graphene/nickel foam electrode is closely related to the presence of highly conductive graphene layer on nickel foam, which can remarkably boost the charge-transfer process at electrolyte electrode interface. The three-dimensional graphene/nickel foam substrate also significantly improves the electrochemical cycling stability of the electrodeposited Ni(OH)(2) film because of the strong adhesion between graphene film and electrodeposited Ni(OH)(2) nanoflakes. Results of this study provide an alternative pathway to improve the rate capability and cycling stability of Ni(OH)(2) nanostructure electrode and offer a great promise for its applications in supercapacitors. Copyright
The fractional model of the electrochemical capacitor (EC) and its potential relaxation are
presented. The potential relaxation occurs after charge or discharge current interruption.
The EC fractional model is based on the fractional order transfer function that was
obtained by means of least squares fitting of the EC impedance data. The inverse Laplace
transform is used to obtain the EC impulse response. By using of the EC impulse response
the EC charge and discharge simulation were performed.
Large-scale deployment of intermittent renewable energy (namely wind energy and solar PV) may entail new challenges in power systems and more volatility in power prices in liberalized electricity markets. Energy storage can diminish this imbalance, relieving the grid congestion, and promoting distributed generation. The economic implications of grid-scale electrical energy storage technologies are however obscure for the experts, power grid operators, regulators, and power producers. A meticulous techno-economic or cost-benefit analysis of electricity storage systems requires consistent, updated cost data and a holistic cost analysis framework. To this end, this study critically examines the existing literature in the analysis of life cycle costs of utility-scale electricity storage systems, providing an updated database for the cost elements (capital costs, operational and maintenance costs, and replacement costs). Moreover, life cycle costs and levelized cost of electricity delivered by electrical energy storage is analyzed, employing Monte Carlo method to consider uncertainties. The examined energy storage technologies include pumped hydropower storage, compressed air energy storage (CAES), flywheel, electrochemical batteries (e.g. lead–acid, NaS, Li-ion, and Ni–Cd), flow batteries (e.g. vanadium-redox), superconducting magnetic energy storage, supercapacitors, and hydrogen energy storage (power to gas technologies). The results illustrate the economy of different storage systems for three main applications: bulk energy storage, T&D support services, and frequency regulation.
Wind diesel power systems (WDPSs) are isolated microgrids which combine wind diesel generators with wind turbine generators. If the WDPS includes a short-term energy storage system (ESS) both the logistic and the dynamic operation are improved. Flywheel based energy storage systems (FESSs) have characteristics that make them very appropriate to be used as short-term ESS in WDPS, so that a FESS, is added to the WDPS. The FESS main components: electrical machine, flywheel, grid converter and electrical machine converter are described. As the main aim of the FESS in the present article is power quality improvement, a robust low cost low-speed FESS (LS-FESS) is selected. The LS-FESS which includes an asynchronous machine (ASM) and a steel flywheel is sized for a particular WDPS. The FESS power converters and ASM can be controlled as if they were a servo but, in order to attain more robustness, it is better to control the ASM converter to maintain a constant DC-voltage in the DC-link and to control the grid converter to exchange the necessary power references with the isolated grid. Finally, in order to verify the proposed low speed FESS, it is simulated along with the WDPS. Simulation results with graphs for the isolated power system frequency and voltage, active powers generated/consumed by the WDPS elements, the FESS-ASM direct and quadrature currents and FESS-flywheel speed are presented for load and wind speed steps. The simulations show a power quality improvement of the isolated microgrid due to the use of the FESS.
This paper examines both the potential of and barriers to grid-scale energy storage playing a substantive role in transitioning to an efficient, reliable and cost-effective power system with a high penetration of renewable energy sources. Grid-scale storage is a term that describes a number of different technologies with a wide range of characteristics. This versatility leads to the use of storage to perform a number of grid-services. We first enumerate these services, with an emphasize on those that are best suited to mitigate the effects of uncertainty and variability associated with intermittent, non-dispatchable renewable energy sources. We then provide an overview of the current methods to evaluate grid-integrated storage, summarize key findings, and highlight ongoing challenges to large-scale adoption of grid-scale energy storage. We focus on one particular area that is critical to both the efficient use of energy storage in the power grid and its long-term economic viability: the conflict between the technical benefits of this resource, which can provide both power and energy related grid-services (in some cases simultaneously), and the economic challenges of compensating these services within the current market structures. We then examine recent progress in addressing these issues through regulatory changes and other initiatives designed to mitigate previous market failures. This discussion is followed by some remarks about ongoing regulatory and market design challenges. The paper closes with a summary of the ideas presented and a discussion of critical research needs.
Many countries worldwide have committed themselves to reducing the rate in which they emit greenhouse gasses. These emissions are the major driver behind human induced global warming. Renewable electricity implementation is one way of reducing the amount of greenhouse gas emissions. However, this transition is also accompanied by some problems. The intermittency of renewables demands for a more flexible electricity system. In existing electricity systems this lack of flexibility already leads to load balancing issues increasing costs and threatening energy security.
Large scale storage facilities could provide the needed flexibility. This paper focuses on the economic and environmental system consequences of the application of power-to-gas, pumped hydro storage and compressed air energy storage in an electricity system at different wind power penetration levels.
The study shows that the application of large scale energy storage techniques results in economic costs reducing effects on the electricity system. These are highest for pumped hydro storage, followed by the cost reducing effects of compressed air energy storage and power-to-gas. The impact on the fuel use and the emissions is less obvious. In some scenarios, the application of storage even resulted in an increase of the fuel use and the emissions.
Energy price is rising due to rapid depletion of fossil fuels. Development of renewable and non-polluting energy resources is necessary for reducing pollution level caused by those conventional fuels. Researchers have recognized hydrogen as such an energy source. Hydrogen is a potential non-carbon based energy resource, which can replace fossil fuels. Hydrogen is considered as the alternative fuel as it could be generated from clean and green sources. Despite many advantages, storage of hydrogen is a serious problem. Due to high inflammability, adequate safety measures should be taken during the production, storage, and use of H2 fuel. This review article elucidates production methods and storage of hydrogen. Besides this safety related to H2 handling in refilling station, and automobiles has also been discussed. Study shows that safety program and awareness could be fruitful for increasing the acceptance of hydrogen as fuel.
The optimal control of state-of-charge (SOC) for superconducting magnetic energy storage (SMES), which is used to smooth power fluctuations from wind turbine, is essential to improve its technical and economical performance. Without an efficient control strategy, the SMES may go to the state of over-charge or deep-discharge, which will pose a significant effect on its service life and its technical performance. In this study, combined with wind forecasting technology and real-time monitoring of SOC for the SMES, a double fuzzy logic control strategy is proposed that is applied to regulate SOC of SMES with the purpose of not only effectively smoothing the power fluctuations of wind turbine, but also preventing the SMES from occurring of the state of over-charge/deep-discharge and adjusting it to the appropriate SOC. The effectiveness of the proposed control strategy is verified by the simulation results.
This paper presents the progress of thermoelectric power generation systems and their potential to be incorporated in small to medium scale power generation systems with encouraging prospects of grid connection. To begin with this paper demonstrates the urgency and necessity of finding an alternative source of energy to replace the existing inclination of human race towards fossil fuels. Following this the potential of thermoelectric technology to be used with alternate energy sources is demonstrated. Development in the field of thermoelectric materials with high Seebeck coefficients, suitable for power generation modules is discussed in the literature review. New advanced materials and innovative techniques to utilise renewable energy for power generation using thermoelectric generators are described in the main body of this paper. Various active and passive cooling systems with thermoelectric power generation modules to enhance the performance of the system are illustrated in the paper. A brief literature survey is presented at the end about grid connection for thermoelectric generators .These advances in thermoelectric technology, places it in a comfortable position to become a major contributor to renewable and sustainable electricity production in the future, essentially replacing fossil fuels.
We attempt to meet the general design requirements for high-performance supercapacitor electrodes by combining the strategies of light-weight substrate, porous nanostructure design and conductivity modification. We fabricate a new type of 3D porous and thin graphite foams (GF) and use as the light and conductive substrates for the growth of metal oxide core/shell nanowire arrays to form integrated electrodes. The nanowire core is Co3O4 and the shell is a composite of conducting polymer (Poly (3,4-ethylenedioxythiophene), PEDOT) and metal oxide (MnO2). To show the advantage of this integrated electrode design (viz., GF+Co3O4/PEDOT-MnO2 core/shell nanowire arrays), three other different less-integrated electrodes are also prepared for comparison. Full supercapacitor devices based on the GF+Co3O4/PEDOT-MnO2 as positive electrodes exhibit the best performance compared to other three counterparts due to an optimal design of structure and a synergistic effect.
Activated carbon cloth is used as an electrode, achieving an excellent areal capacitance of 88 mF/cm(2) (8.8 mF/g) without the use of any other capacitive materials. Significantly, when it is incorporated as part of a symmetric solid-state supercapacitor device, a remarkable charge/discharge rate capability is observed; 50% of the capacitance is retained when the charging rate increases from 10 to 10 000 mV/s.
In this paper, an updated review of the state of technology and installations of several energy storage technologies were presented, and their various characteristics were analyzed. The analyses included their storage properties, current state in the industry and feasibility for future installation. The paper includes also the main characteristics of energy storage technologies suitable for renewable energy systems.
Interest in compressed air energy storage (CAES) technology has been renewed driven by the need to manage variability form rapidly growing wind and solar capacity. Distributed CAES (D-CAES) design aims to improve the efficiency of conventional CAES through locating the compressor near concentrated heating loads so capturing additional revenue through sales of compression waste heat. A pipeline transports compressed air to the storage facility and expander, co-located at some distance from the compressor. The economics of CAES are strongly dependant on electricity and gas markets in which they are embedded. As a case study, we evaluated the economics of two hypothetical merchant CAES and D-CAES facilities performing energy arbitrage in Alberta, Canada using market data from 2002 to 2011. The annual profit of the D-CAES plant was 40/tCO2e. We performed a suite of sensitivity analyses to evaluate the impact of size of heat load, size of air storage, ratio of expander to compressor size, and length of pipeline on the economic feasibility of D-CAES.
