Volume 64

Compressed CO₂ energy storage using high-temperature TES for isolated islands Yuemao Jiang, Shunsen Wang, Haotian Zhao, Bo Li

Abstract

Isolated islands have a high potential for renewable energy exploitation due to their unique geography. However, the intermittency of these resources requires energy storage systems to ensure a reliable power supply. This study proposes an advanced compressed CO₂ energy storage system integrating a high-temperature thermal energy storage (TES) architecture for isolated island applications. The system exploits seawater static pressure and ocean thermal energy to enable liquid CO₂ isobaric storage, while employing pressurized water and molten salt in a dual-loop TES configuration. Thermodynamic design and performance of the system are modelled under realistic assumptions for all components. A parametric analysis is then conducted to investigate the effects of key parameters on the overall system performance. Results show that the system can achieve a round-trip efficiency of 74.7% and a storage density of 61.1 kWh/m³, provided that an appropriate seawater depth is available. This study offers valuable insights for advancing CCES systems.

Keywords isolated island, compressed CO₂ energy storage, ocean thermal energy, thermal energy storage