Dynamic Modeling of Gasbag-Structured Compressed Supercritical Carbon Dioxide Energy Storage

To mitigate the adverse effects of high-penetration renewable energy, large-scale, long-duration energy storage systems (LSLD-ESSs) have gained significant attention. Currently, feasible LSLD-ESSs, such as pumped hydro energy storage (PHES) and compressed air energy storage (CAES), face limitations due to specific terrestrial constraints. To address these challenges, gasbag-structured compressed supercritical carbon dioxide energy storage (G-CSCES) has been developed. However, existing studies primarily focus on exergoeconomic optimization, and current cavern-structured CAES models are not applicable to G-CSCES, hindering its use for ancillary services. This letter proposes a comprehensive dynamic model for G-CSCES, encompassing thermodynamic and power dynamic, to enhance its application for frequency regulation in power systems. The proposed model is tested on a real G-CSCES.