Battery Storage System Research Articles

Improved Whale Optimization Algorithm for Solving Microgrid Operations Planning Problems

Microgrid operations planning is one of the keys to ensuring the safe and efficient outputs of distributed energy resources (DERs) and the stable operation of a power system in a microgrid (MG). In this study, for the symmetry in renewable energy and microgrid systems, and coordinated control based on a storage battery system, an MG dispatching model with DER conditions and integrated costs is established in grid-connected mode, on the basis of MG operation costs, interaction costs, and pollutant emissions costs. Moreover, an optimization objective for minimizing integrated costs is established. Therefore, based on the original whale optimization algorithm (WOA), an improved whale optimization algorithm (IWOA) with adaptive weight strategy and Levy flight trajectory is proposed in this paper, to solve the optimal operations planning problem of MGs. Finally, in computing comparisons with methods such as the genetic algorithm (GA), particle swarm algorithm (PSO), WOA, wild horse optimizer (WHO), and enhanced whale optimization algorithm (EWOA), the results show that the IWOA computation had lower integrated costs and higher operational efficiency. Moreover, it is verified that the IWOA performed better in solving the MG operations planning problem.

Life cycle greenhouse gas emissions of residential battery storage systems: A German case study

AbstractBattery storage systems (BSSs) are popular as a means to increase the self‐consumption rates of residential photovoltaics. However, their environmental impact is under discussion, given the greenhouse gas emissions caused by the production and the efficiency losses during operation. Against this background, we carry out a holistic environmental assessment of residential BSSs by combining a partial life cycle assessment for the production phase with a detailed simulation of 162 individual German households for the operational phase. As regards the production phase, we only find small differences between the carbon footprints of different cell chemistries. Moreover, we can show that the balance of plant components have a comparable impact on the global warming potential as the cell modules. In terms of the operational phase, our simulations show that BSSs can compensate at least parts of their efficiency losses by shifting electricity demand from high‐emission to low‐emission periods. Under certain conditions, the operational phase of the BSSs can even overcompensate the emissions from the production phase and lead to a positive environmental impact over the lifetime of the systems. As the most relevant drivers, we find the exact emissions at the production stage, the individual household load patterns, the system efficiency, and the applied operational strategy.

Analysis of a self-sufficient photovoltaic system for a remote, off-grid community

Background A photovoltaic (PV) system, especially the stand-alone type, along with a battery storage system, plays a significant role in providing the needed electrical energy to remote, off-grid communities. Methods In this study, a stand-alone PV solar cell was enhanced to better understand the system operation. Modeling and simulation were performed using MATLAB software. Results This work has shown that the I-V (current-voltage) and P-V (power-voltage) characteristics of the modelled system have a profound effect on energy when a pulse width modulation controller is used as a charger. The modelled PV system generated the required energy under different conditions, considering temperature and PV battery voltage mismatches. Conclusion In summary, the simulated model in this study can be considered a system capable of detecting different conditions with the presence or absence of light at different temperatures. Finally, monitoring the temperatures, adjusting the voltage with a suitable charger controller, and selecting solar modules made of optimal materials can increase the efficiency of the solar system and allow it to be used in more applications.

Frequency and Voltage Stability of Distribution Network using Photovoltaic Stabilization System and Battery Storage System

In a power system, various factors such as changes in generator output power due to load changes and different types of short circuits may change the network frequency/voltage as a consequence of changes in network condition. These volatilities in frequency/voltage may cause system frequency/voltage instability. Among different devices used for power system stability, stabilizers are the most important equipment for network stabilization and generator synchronization. In this paper, a photovoltaic system accompanied by battery storage system is used to improve the power system stability following voltage/frequency sudden variations as a result of unpredicted events in the distribution network. To do that, an IEEE 14-bus standard test network is simulated in MATLAB/Simulink, and the performance of the proposed system after different common disturbances is investigated. The results verify the performance of the proposed stabilizer so that it maintains the system stability successfully with zero percent deviation from the original state of the network.

Modelling and simulation of a storage system connected to a wind farm under ramp-rate limitation

ABSTRACT Ramp-rate limitation is a strategy to reduce wind power variability and to permit the integration of wind power into the grid. However, penalties occur whenever the ramp-rate limitations are not respected. The purpose of this paper is to compute the penalties to which a wind farm may undergo when a battery storage system is put alongside the wind farm. This is achieved by advancing a semi-Markov model which mimes the operations on the battery and considers a new reward structure which is dependent on the time length of the battery operations. Two Monte Carlo algorithms are proposed for simulating the penalty process. The paper shows the validity of the methodology by verifying the model assumptions directly on real data and through a comparison of the real and the simulated results. This paper contributes to the literature by extending previous stochastic models and providing a general methodology for the economical characterization of ramp-rate limitation policies.

Closing gaps in LCA of lithium-ion batteries: LCA of lab-scale cell production with new primary data

Battery storage systems have become an important pillar in the transformation of the energy and transportation sector over the last decades. Lithium-ion batteries (LIBs) are the dominating technology in this process making them a constant subject of analysis regarding their sustainability. To assess their environmental performance, several Life Cycle Assessments (LCA) of LIBs have been performed over the last years. Yet, the amount of available primary data on their production remains low, leading to recurrent reliance on a few disclosed datasets, mostly at industrial scale. Thus, there is a need for new LCA studies at different scales (lab, pilot, industrial) using transparent datasets to facilitate more reliable and robust assessments. This work presents a screening of recent environmental assessments for LIBs at different production scales aiming at identifying remaining gaps and challenges, and deriving a detailed LCA of a lab-scale battery cell production. For the first time the environmental impact of a lab-scale battery production based on process-oriented primary data is investigated. The results are flanked by sensitivity analyses and scenarios and compared with literature values. The hotspots identified in this study, cathode slurry, anode current collector, as well as the energy demand of the dry room and coating process, are consistent with the literature, although the absolute values are an order of magnitude larger. The main reason for this are the inefficiencies inherent in lab-scale production. In order to analyze the effects of production scale, an upscaling to the pilot scale is performed.

Insights into the use of polyepichlorohydrin polymer in lithium battery energy storage/conversion devices: review

Abstract In this paper, the up-to-date state of polyepichlorohydrin-based electrolytes is reviewed. Research works are persistently ongoing to develop free-standing solid polymer electrolytes with exceptional performances and stabilities that can suit the needs of present and next-generation technologies. Polyepichlorohydrin (PECH), for example, is one of the polymer hosts under consideration due to its ether electron donor groups that deliver coordinating spots for cation transport as well as alkyl chloride groups for changing its surface character. Because of this structure, PECH has certain incredible characteristics including small glass transition temperature (Tg), tremendous flexibility, as well as the power to form complexation with diverse salts. Furthermore, the alkyl chloride groups serve as a location for surface modification of the polymer via nucleophilic substitution reactions, resulting in surface changes or bulk properties. As a result, the PECH in chemically modified or pristine form is an emerging option that has been researched and is being considered for use in energy storage devices. This paper reviews the latest studies on the improvements of PECH-based electrolytes for lithium-based battery storage systems. The synthesis methods of PECH polymer, types of lithium batteries, and opportunities and challenges of lithium batteries have been presented briefly. Findings on PECH-based electrolytes have been presented and discussed thoroughly. Lastly, the paper presents, battery performance needs, and cation transportation mechanisms as well as future prospects for the advancement of PECH electrolytes in the field of storage systems. Article Highlights The alkyl chloride groups of polyepichlorohydrin polymer play a significant role in modifying the characteristics of the polymer through chemical reactions. The inherent characteristics of PECH-based polymers including their amorphousity, glass transition temperature, functionality, and others can be altered via chemical and physical means. The impressive electrochemical characteristics of PECH-based electrolytes make them a viable option for energy storage/conversion devices applications as electrolytes.

A Multiport Partial Power Processing Converter With Energy Storage Integration for EV Stationary Charging

Battery storage system (BSS) integration in the fast charging station (FCS) is becoming popular to achieve higher charging rates with peak-demand shaping possibility. However, the additional conversion stage for integrating the BSS increases the system losses, size, and cost. The concept of a partial power processing converter (PPPC) can mitigate this effect. Compared to conventional used full power processing converter (FPPC), PPPC reduces the amount of transferred power from the BSS to the electric vehicle (EV) by the converter. As a consequence, the power losses generated by the converter are reduced, leading to lower sized converters and higher system efficiencies. This article proposes a dc/dc multiport converter that allows the integration of battery storage in FCS based on a partial power processing concept while maintaining the specific requirements in terms of isolation for FCS. The proposed three-port partial power processing converter (3P-PPPC) is derived from the commonly used triple active bridge (TAB) converter. The resulting design tradeoffs, the dynamic behavior, and limitations of the topology are investigated. Furthermore, the round-trip efficiency of the 3P-PPPC for integrating BSS in FCS is compared with conventional FPPC solutions, highlighting the superiority of the proposed topology. A prototype has been built to validate the 3P-PPPC.

Behind-the-Meter Resources: Data-driven modeling, monitoring, and control

Behind-The-Meter (BTM) resources are distributed energy resources (DERs), such as rooftop solar photovoltaics (PVs), electric vehicles, and battery storage systems, located on the customer side of smart meters. Driven by monetary incentives, declining costs, and increasing electricity service interruptions, the penetration of BTM resources has been increasing exponentially in the past few years. For example, the small-scale BTM solar PV capacity in the United States has quickly increased from 7,642 MWac in September 2015 to 34,029 MWac in February 2022.

Power control strategy of a photovoltaic system with battery storage system

In this paper, an intelligent approach based on fuzzy logic has been developed to ensure operation at the maximum power point of a PV system under dynamic climatic conditions. The current distortion due to the use of static converters in photovoltaic production systems involves the consumption of reactive energy. For this, separate control of active and reactive powers using a proportional-integral controller is applied. Using batteries for energy storage in the photovoltaic system has become an increasingly promising solution to improve energy quality: current and voltage. For this purpose, the energy management of batteries for regulating the charge level under dynamic climatic conditions has been studied. The research presented in this paper provides an important contribution to the application of fuzzy theory to improve the power and performance of a hybrid system comprising a grid-connected PV, battery, and energy management strategy. Therefore, to highlight the advantage of the FL-MPPT studied in this paper, its performance has been compared and analyzed with conventional P&O and NNT algorithms. Simulation results are carried out in MatLab/Simulink tools. According to the analysis of the results, a better energy quality has been proven.

Battery Storage System as Power Unbalance Redistributor in Distribution Grids Based on Three Legs Four Wire Voltage Source Converter

This article discusses the application of battery energy storage systems (BESSs) as power redistributors in three-phase distribution grids as an add-on functionality to typical BESS applications, such as congestion management and energy arbitrage. Combining those ancillary services into a single power unit is not yet performed in practice but may constitute an emerging business opportunity to increase the BESS revenues. The unbalanced operation of the BESS voltage source converter (VSC) leads to the circulation of low-frequency current harmonics in the dc-link through the capacitors and the battery cells. Therefore, it is particularly interesting whether relatively large 50- and 100-Hz currents can safely circulate within these components. Analytical modeling and design guidelines for the dc-link of a three-leg four-wire two-level VSC operating under unbalanced loads are detailed. Furthermore, a low-power VSC prototype is used to demonstrate the working principle of the BESS, providing power unbalance redistribution and symmetric power exchange. Additionally, the ICR18650-26F Lithium-ion cells are cycled to reach end-of-life with different current profiles and C-ratings. The analysis shows that charging with a 100 Hz ripple superimposed to the dc current leads to a 10% increment in degradation.

An optimal real-time pricing strategy for aggregating distributed generation and battery storage systems in energy communities: A stochastic bilevel optimization approach

The expansion of distributed electricity generation and the increasing capacity of installed battery storage systems at the community level have posed challenges to efficient technical and economic operation of the power systems. With advances in smart-grid infrastructure, many innovative demand response business models have sought to tackle these challenges, while creating financial benefits for the participating actors. In this context, we propose an optimal real-time pricing (ORTP) approach for the aggregation of distributed energy resources within energy communities. We formulate the interaction between a community-owned profit-maximizing aggregator and the users (consumers with electricity generation and storage potential, known as “prosumagers”, and electric vehicles) as a stochastic bilevel disjunctive program. To solve the problem efficiently, we offer a novel solution algorithm, which applies a linear quasi-relaxation approach and an innovative dynamic partitioning technique. We introduce benchmark tariffs and solution algorithms and assess the performance of the proposed pricing strategy and solution algorithm in four case studies. Our results show that the ORTP strategy increases community welfare while providing useful grid services. Furthermore, our findings reveal the superior computational efficiency of our proposed solution algorithm in comparison to benchmark algorithms.

Optimal energy management of nanogrid using battery storage system

This paper presents the optimal energy management approach with optimum sizing of the battery storage system (BSS) for the minimal possible total operating cost of the considered nanogrid. The five various operating modes are tested to achieve the optimal operating mode on an hourly basis. Linear programming (LP) is used to get optimal solutions for objective functions having non-integer variables whereas mixed-integer linear programming (MILP) is used to optimize the objective function having an integer variable. The proposed hourly-based optimal operating mode produces 17.8–94.5 % savings in the day operating cost compared to the best individual operating mode. The optimal capacity of the battery storage system is also derived by using the proposed operating modes. The achieved optimal capacity of BSS based on the day operating cost is further modified with the help of investment cost and its interest paid during the life span which suggests that the optimal capacity range will be 4–19 kWh for this nanogrid.

A multi-objective optimisation strategy exploring the energy routing capability of a smart transformer while integrating hybrid energy hub into a distribution network

This study proposes an optimal planning approach for exploiting the energy routing capabilities of a smart transformer (ST) while integrating a hybrid energy hub (HEH) comprised of a wind turbine generator (WTG) and a battery storage system (BSS) into a distribution network (DN). An efficient energy management strategy (EMS) regulates energy exchanges within the HEH unit and with the utility grid. The work presents a mixed-integer nonlinear programming (MINLP) problem for optimising the HEH planning parameters with the purpose of minimizing network performance costs such as line loading, real and reactive power losses, voltage profile, and asset management costs. Two approaches are used to achieve the goals, with the first strategy focused on network performance costs, while the second combines the network performance and the asset management expenses. The proposed methodology was tested using the 33-bus radial distribution network (RDN) alongwith a real-life 108-bus Indian RDN, and the results of various case studies are reported. The MATLAB R2020a programming platform has been used to solve the MINLP problem using the posteriori approach based paretosearch algorithm (PSA). The outcomes of the evaluation show an apparent energy loss reduction of 58.44%, a line loading improvement of 36.24%, and a voltage deviation improvement of 68.24%.

Potential analysis of current battery storage systems for providing fast grid services like synthetic inertia – Case study on a 6 MW system

Large-scale battery energy storage systems (BESS) already play a major role in ancillary service markets worldwide. Batteries are especially suitable for fast response times and thus focus on applications with relatively short reaction times. While existing markets mostly require reaction times of a couple of seconds, this will most likely change in the future. During the energy transition, many conventional power plants will fade out of the energy system. Thereby, the amount of rotating masses connected to the power grid will decrease, which means removing a component with quasi-instantaneous power supply to balance out frequency deviations the millisecond they occur. In general, batteries are capable of providing power just as fast but the real-world overall system response time of current BESS for future grid services has only little been studied so far. Thus, the response time of individual components such as the inverter and the interaction of the inverter and control components in the context of a BESS are not yet known. We address this issue by measurements of a 6 MW BESS's inverters for mode changes, inverter power gradients and measurements of the runtime of signals of the control system. The measurements have shown that in the analyzed BESS response times of 175 ms to 325 ms without the measurement feedback loop and 450 ms to 715 ms for the round trip with feedback measurements are possible with hardware that is about five years old. The results prove that even this older components can exceed the requirements from current standards. For even faster future grid services like synthetic inertia, hardware upgrades at the measurement device and the inverters may be necessary.

A Review of Peer-to-Peer Energy Trading with Standard Terminology Proposal and a Techno-Economic Characterisation Matrix

Nowadays decarbonisation of the energy system is one of the main concerns for most governments. Renewable energy technologies, such as rooftop photovoltaic systems and home battery storage systems, are changing the energy system to be more decentralised. As a consequence, new ways of energy business models are emerging, e.g., peer-to-peer energy trading. This new concept provides an online marketplace where direct energy exchange can occur between its participants. The purpose of this study is to conduct a content analysis of the existing literature, ongoing research projects, and companies related to peer-to-peer energy trading. From this review, a summary of the most important aspects and journal papers is assessed, discussed, and classified. It was found that the different energy market types were named in various ways and a proposal for standard language for the several peer-to-peer market types and the different actors involved is suggested. Additionally, by grouping the most important attributes from peer-to-peer energy trading projects, an assessment of the entry barrier and scalability potential is performed by using a characterisation matrix.

Functional CNTs@EMIM+ -Br- Electrode Enabling Polysulfides Confining and Deposition Regulating for Solid-State Li-Sulfur Battery.

With an extremely high theoretical energy density, poly(ethylene oxide) (PEO)-based solid-state lithium-sulfur (Li-S) batteries are emerging as one of the most feasible and safest battery storage systems. However, the long-term cycling performance is severely impeded by polysulfides (Li2 Sn , n=4-8) shuttling and terrible electrode passivation from the electronic insulating Li2 S. Here, a novel cathode through chemically grafted 1-Ethyl-3-methylimidazolium bromide (EMIM+ -Br- ) to carbon nanotube (CNTs) for PEO-based Li-S batteries is reported (CNTs@EMIM-Br/S). Concretely, bi-functional mediator EMIM+ -Br- not only inhibits the polysulfides shuttling by strong chemical interactions via EMIM+ , but also facilitates the electrochemical kinetics for promoting the formation of 3D particulate Li2 S through high donor anion (Br- ). Satisfactorily, dual-function CNTs@EMIM-Br/S cathode exhibits high sulfur utilization with the capacity of up to 1298mAhg-1 , and keeps high capacity retention of 80.2% at 0.2C after 350 cycles, exceeding that of many reported PEO-based solid-state Li-S batteries. This work will open a new door for rationally designed architecture to enable the practical applications of advanced Li-S batteries.

Design Space Exploration of Lithium-Ion Battery Packs for Hybrid-Electric Regional Aircraft Applications

Distributed hybrid and electric propulsion systems are one of the most promising technologies to reduce aircraft emissions, resulting in research efforts to investigate new architectures and the design of optimal energy management strategies. This work defines the optimal requirements in terms of battery pack sizing and cell technology for a hybrid-electric regional wing-mounted distributed propulsion aircraft through the application of a design space exploration method. The propulsion system considered in this study is a series-parallel hybrid turboelectric power train with distributed electric fans. A set of six lithium-ion battery cell technologies was identified and experimentally characterized, including both commercially available and prototype cells at different combinations of specific energy and power. A model of the aircraft was developed and used to define the optimal energy management strategy for the hybrid turboelectric propulsion system, which was solved using dynamic programming. The design space exploration was conducted by varying the cell technology and battery storage system size; and the effects on fuel consumption, energy management strategy, and thermal management were compared.

Modeling and analysis of hybrid solar water desalination system for different scenarios in Indonesia

Clean water demand has significantly increased due to the rise in the global population. However, most water on the Earth has high saline content that cannot be consumed directly; only about one over forty of the total water source is freshwater. Desalinated water is one of the potential solutions to meet the growing demand for freshwater, which is highly energy intensive. This paper analyses the energy, economic and environmental performance of a 5 m3/day PV (photovoltaic) powered reverse osmosis (RO) desalination system. Three scenarios of PV-RO with and without battery storage and diesel generator hybrid systems have been analyzed and investigated for the annual estimate load, net present value, and payback period of the water and electricity production costs. Also, the CO2 avoidance over the lifetime operation of all scearios is evaluated. This study shows that the PV-RO system without battery with 6.3 kW PV panels installed and with a 2-days water storage tank system is the most profitable economically f. For this scenario, the Levelized Cost of Electricity (LCOE), Levelized Cost of Water (LCOW), and Payback Period (PBP) are found to be $0.154/kWh, $0.627/m3, and five years, respectively. In addition, for this scenario, the CO2 emissions avoidance was the maximum (111,690 kg.CO2eq per year) compared to other scenarios.

Smart techno-economic operation of electric vehicle charging station in Egypt

Stochastic fast-charging of electric vehicles (EVs) affect the security and economic operation of the distribution power network. Aggregator awareness in the electric power industry is fast growing in tandem with the growing number of EVs. This paper proposes a novel smart techno-economic operation of the electric vehicle charging station (EVCS) in Egypt controlled by the aggregator based on a hierarchal model. The deterministic charging scheduling of the EVs is the upper stage of the model to balance the generated and consumed power of the station and flat the surplus power supplied to the utility grid. Mixed-integer linear programming (MILP) is used to solve the first stage where the peak demand value is reduced to 48.17% (4.5 kW) without using any extra battery storage systems. The second challenging stage is to maximize the charging station profit whilst minimizing the EV charging tariff, which needs a trade-off. In this stage, MILP and Markov Decision Process Reinforcement Learning (MDP-RL) resulted an increase in EVCS revenue by 28.88% and 20.10%, respectively. However, the EVs charging tariff is increased by 21.19%, and 15.03%, respectively. Hence, MDP-RL is an adequate algorithm for such a complex model. The outcomes reveal a sufficient techno-economic hierarchal model concerning the normal operation stated in the literature.