Thermodynamic and Techno-Economic Assessment of Liquid Air Energy Storage Integrated with Liquid Hydrogen Regasification and Cryogenic Thermal Energy Storage

Large-scale liquid hydrogen (LH2) terminals provide a cryogenic resource during regasification. This study compares a base LH2-assisted liquid air energy storage (LAES) configuration with propane thermal energy storage (TES) coupled to an ethylene–propane cascade organic Rankine cycle (ORC). A component model includes periodic storage inventories, exchanger pressure losses, finite seawater streams and active tank refrigeration. For eight-hour charging and six-hour discharge, the electricity return ratios of the base and TES configurations are 148.69% and 187.79%, respectively. These electrical ratios exclude the external cold resource. Electrical exergy efficiencies, including hydrogen physical-exergy depletion, are 22.10% and 22.93%. TES reduces daily grid imports by 72.67 MWh and supplies 89.12 MW during discharge. At the selected electricity prices and 2026 Korean corporate tax rates, the maximum additional TES investment for equal net present value is 19.65 million USD on the principal capital basis. The quantity-based equipment estimate exceeds this increment, indicating that the thermodynamic gain requires lower incremental capital or different commercial conditions to become economically attractive. Detailed equipment engineering and whole-plant validation remain necessary.