## 2 Battery and Hydrogen Energy Storage System
### Integration of BESSs and HESSs
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**No** & **Case** & **Details** & **Author/ Year** \\ \hline \multirow{9}{*}{3} & Optimal Capacity & This study discusses the difficulties caused by the unpredictable and sporadic character of new energy sources, which have an impact on the stability of system output power. The study suggests combining a hydrogen energy storage system with solar, wind, and hydrogen energy to lessen these problems. The objectives of this integration are to increase the use of renewable energy, encourage its consumption, and lower the rates at which solar and wind energy are being curtailed. By employing methodologies for charging and discharging storage batteries and hydrogen energy storage, the system maximizes operation cost efficiency, controls power variations, and handles power shortages. In order to set up the ideal combination of wind, solar, and hydrogen capacities, it creates a model for optimizing the capacity allocation of a wind-hydrogen microgrid system. For a wind-hydrogen storage microgrid, the study uses the particle swarm optimization method with dynamic adjustment of inertial weight (IDW-PSO) to find the best allocation scheme and guarantee effective energy storage capacity. With the use of Beijing microgrid system simulations, the efficacy of the suggested method is shown. The strategy improves economic efficiency, increases the system’s ability to consume renewable energy, lessens power fluctuations, lessens power shortages, and speeds up the system’s convergence speed, according to the results. \\ \hline \multirow{9}{*}{4} & In response to the growing need for low-carbon transportation, the article looks into energy storage methods for wind and photovoltaic systems. The importance of energy storage systems (ESSe) as vital parts of renewable energy systems has recently come to light. The system requirements, financial constraints, and performance attributes all play a role in the technology selection process. For renewable energy sources, ESs come in a variety of forms. These include electrochemical storage, which includes batteries, hydrogen storage fuel cells, and flow batteries; mechanical storage, which includes flywheels, pumped hydroelectric energy storage (PHES), gravity energy storage (GES), compressed air energy storage (CAES), and supercapacitors; electrical storage, which includes supercapacitors, SMES, and thermal energy storage (TES); and hybrid or multi-storage systems, which combine multiple technologies (e.g., supercapacitors and thermal energy storage or batteries and pumped hydroelectric storage). With the help of these several ES categories, excess energy from renewable sources may be efficiently stored and released, guaranteeing a steady and reliable supply of energy. Precise system requirements determine which storage technology is best for a given application in solar and wind systems. When choosing an ES technology, it is critical to consider aspects like power and energy demands, efficiency, cost-effectiveness, scalability, and durability. \\ \hline \multirow{9}{*}{5} & The difficulties encountered in isolated locations where it is not feasible to economically extend the electrical grid beyond the maximum breakeven distance are covered in this study. It suggests a workable solution for these areas: an integrated autonomous sustainable energy system. The paper presents a brand-new multi-optimization power management and electrical energy evaluation system designed specifically for microgrid networks. This system interfaces with a hybrid configuration of energy sources, comprising the grid network, downdraft biomass generator, and solar photovoltaic arrays. It includes integrated dispatch, load-following, and cycle-charging algorithms as a control module. In addition, it integrates flywheels, iron flow, lithium, sodium sulfur, and hybrid energy storage technologies with thermal load controller-boiler systems. When combined, these components allow the microgrid to function effectively in off-grid, grid-connected, and island-capable modes, giving it the freedom to cut off from the main grid when necessary. An optimal multitask control technique is used to manage the storage units and modeled power generation sources through the use of the HOMER software application. This strategy reduces energy losses, guarantees efficient storage management, boosts overall system efficiency, and lengthens the microgrid’s operating life. In the end, this integrated energy system may be deployed in both rural and urban settings, providing sustainable energy solutions appropriate for a range of economic and environmental circumstances. \\ \hline \hline \end{tabular}
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