•An improved operation strategy for decentralized A-CAES is proposed.•TES behavior and its effects on A-CAES performance are analyzed.•Characteristics and capacity limitations of HES's components are ...considered.•A parametric study showed an optimum value for the system's design parameters.•Improved operation strategy reduced the ramp-up /down rate by around 4% /11%.
Adiabatic compressed air energy storage (A-CAES) has shown great application potentials in integrated hybrid energy systems (HES) in recent years. The integration requires A-CAES to store intermittent renewables power to meet the fluctuating load demand. Therefore, the operation of compressors and turbines must be adjusted by renewable power output and load demand, respectively. This paper presents an improved energy management operation strategy (I-EMOS) to enhance the A-CAES system's utilization for decentralized applications. In doing so, besides integrating thermal energy storage (TES) unit into CAES, several limitations of an A-CAES unit, such as its conversion process mode, dynamic characteristics, power input/output constraints of compressor/turbine train, air pressure constraint, and thermal storage capacity limitations are considered. An HES consisting of PV, A-CAES, and grid to answer the building's electric demand is simulated. The results are validated against data from an existing A-CAES pilot. It is concluded that adopting features and capacity limitations of the A-CAES system's power conversion unit in operational strategies contributes to improved management of energy flow in HES. It is observed that for certain air tank volume and maximum/minimum pressures under I-EMOS, an enhanced performance can be achieved. This analysis presents a feasibility assessment approach for decentralized A-CAES integrated with renewables implemented and tested in a real-world case study.
Recent research focuses on optimal design of thermal energy storage (TES) systems for various plants and processes, using advanced optimization techniques. There is a wide range of TES technologies ...for diverse thermal applications, each with unique technical and economic characteristics. Matching an application with the most suitable TES system remains challenging. This study proposes an eight‐step design methodology guiding the process from describing the thermal process to defining the most appropriate TES based on constraints and requirements. The steps include specifying the thermal process, system design parameters, storage characteristics, integration parameters, key performance indicators, optimization method, tools, and design robustness. Seven already‐designed TES systems are evaluated to assess the methodology's effectiveness, where the design procedures have been adapted to the proposed steps. Case studies involve various applications with both sensible and latent TES systems, demonstrating the applicability of the proposed design procedure. A significant diversity exists among the design cases regarding the design objective, input, design, and output parameters. Nevertheless, the design procedure in each case can be deconstructed into the outlined design steps. The last design step has been excluded from all case studies due to insufficient information regarding the robustness of the design process. The paper demonstrates how a methodical approach can be applied to examine the TES design and the integration. The design steps proposed in this study can serve as a foundation for developing a more systematic approach for designing TES systems in future works, resulting in simplifying the design process.
