Fuel cell system

A fuel cell system comprising:

• a fuel cell configured to cause an electrochemical reaction between hydrogen and oxygen, the fuel cell being configured to produce water as a result of the electrochemical reaction;
• a water storage unit configured to store the water recovered from the fuel cell, the water storage unit being configured to be able to drain the stored water;
• a water usage unit configured to use the water in the water storage unit;
• and
• a control unit configured to control a drain of the water from the water storage unit, the control unit being configured to
• when a first predetermined time has elapsed since a last drain of the water from the water storage unit and it is predicted that the water is not used by the water usage unit within a second predetermined time shorter than the first predetermined time, drain the water from the water storage unit, and
• when the first predetermined time has elapsed since the last drain of the water from the water storage unit and it is predicted that the water is used by the water usage unit within the second predetermined time shorter than the first predetermined time, not drain the water from the water storage unit even when the first predetermined time has elapsed since the drain of the water from the water storage unit.