ENERGY STORAGE SYSTEM AND MANAGEMENT APPARATUS

An energy storage system comprises: a generation unit configured to generate liquid fuel using power by renewable energy; a storage unit configured to store the liquid fuel generated by the generation unit; and a storage amount management unit configured to control the generation unit and monitor a storage amount in the storage unit, wherein when the storage amount in the storage unit exceeds a predetermined threshold, the storage amount management unit performs switching such that the power is operated by an operation company of power.