Offshore Charging Infrastructure for Electric Vessels Using Wind Power and Liquid CO₂ Energy Storage

Green Shipping Corridors (GSCs) are a pivotal strategy for reducing pollutant emissions from maritime transport, which contributes approximately 2.9% of global CO₂ emissions. This study proposes a renewable-powered offshore fast-charging station for electric vessels, designed to operate independently of onshore port infrastructure. The station is powered by 20 offshore wind turbines (120 m rotor diameter), operating 12 hours daily at an average wind velocity of 8 m/s. Surplus wind energy is stored using a liquid CO₂ energy storage system, where CO₂ is compressed, liquefied at ambient temperature, and stored in high-pressure tanks. When wind availability is low, the stored CO₂ is vaporized, superheated with recovered compressor heat, and expanded through turboexpanders to regenerate electricity. The system includes a 10 MW fast charger capable of fully recharging a 4 MWh vessel battery in one hour. Thermodynamic analysis shows wind-to-electric efficiency of 36.15%, liquid CO₂ storage roundtrip efficiency of 70.14%, and charging unit efficiency of 95%, resulting in an overall system efficiency of 24.09%. The synergistic integration of offshore wind and liquid CO₂ storage presented in this study enables zero-carbon transition in maritime operations and support the development of GSCs through offshore electrification infrastructure.