FUEL CELL SYSTEM AND METHOD OF OPERATING SAME

A fuel cell system of the present invention includes: a fuel cell (1) configured to generate electric power using a hydrogen-containing fuel gas; a combustible gas path (4, 17, la) including a fuel gas channel (la) of the fuel cell;0 a shutoff valve (21) disposed on the combustible gas path, located upstream of the fuel cell, to close when the fuel cell stops generating the electric power; a casing (11) containing the fuel cell, the combustible gas path, and the shutoff valve; a ventilation fan (12) configured to ventilate the casing; a stop unit (51, 52) configured to stop a ventilation operation of the ventilation fan by a manual operation of an operator; and a controller (10) configured to, when leakage of a combustible gas occurs in the casing, execute the ventilation operation of the ventilation fan as long as the ventilation operation is not stopped by the stop unit.