The present invention provides a technique that enables, in an environment in which an upper limit of electric energy consumption is prescribed for a specific period, operations of a storage device while keeping the electric energy consumption within the prescribed upper limit and, at the same time, maintaining operations of a disk device of a storage device necessary for providing services to a user. A storage system according to the present invention includes a storage device having one or more energized parts and a management device that manages operations of the storage device. The management device acquires electric energy consumption of the energized part and controls the operational state of the energized part so that the electric energy consumption of the storage device over a predetermined period does not exceed a prescribed upper limit.