Fuel cell system

A fuel cell system comprising:

• a fuel cell for generating power by chemically reacting a fuel gas supplied to an anode and an oxygen containing gas supplied to a cathode;
• an anode off-gas discharge mechanism for discharging an anode off-gas from said anode;
• a combustion heater for combusting a combustion gas wherein the combustion gas is at least one of either said anode off-gas or said fuel gas together with the oxygen containing gas, using a thermal energy obtained by the combustion, and heating said fuel cell;
• a dilution mechanism for diluting said anode off-gas by said oxygen containing gas;
• a first path for introducing said anode off-gas into said combustion heater;
• a first flow rate adjustment mechanism for adjusting an introduction amount of said anode off-gas into said first path;
• a second path for introducing said anode off-gas into said dilution mechanism;
• a second flow rate adjustment mechanism for adjusting an introduction amount of said anode off-gas into said second path;
• a third path for introducing said fuel gas into said combustion heater;
• and
• a third flow rate adjustment mechanism for adjusting an introduction amount of said fuel gas into said third path;
• and
• a control mechanism for controlling actuations of said first flow rate adjustment mechanism, of said second flow rate adjustment mechanism, and of said third flow rate adjustment mechanism.