Control apparatus for power supply system, control method for power supply system, and power supply system

The present invention provides a control apparatus for a power supply system. A power supply system according to this embodiment is provided with: a hydrogen power generation device which generates hydrogen by using electric power supplied from a power generation device using renewable energy, and supplies the electric power generated by the generated hydrogen to a load; and a battery which has a faster control response than the hydrogen power generation device and charges/discharges an excessive/insufficient amount of the electric power supplied from the power generation device to the load. This control apparatus for a power supply system is provided with: an acquisition unit which acquires information on the remaining amount of energy in the battery; and a control unit which, on the basis of the information, performs a control to cause the hydrogen generation device to start generating power when it is predicted that the remaining amount of energy in the battery will reach a first threshold value in a predetermined time.