Fuel cell system

A fuel cell system comprising:

• a fuel cell for generating power using a fuel gas supplied to a fuel electrode and an oxidant gas supplied to an oxidant electrode;
• a reformer for generating the fuel gas and supplying the fuel gas to the fuel electrode;
• a fuel cell heating medium circulation circuit for circulating a fuel cell heating medium that exchanges heat with the fuel cell;
• a condensing coolant circulation circuit for circulating a condensing coolant that exchanges heat with at least one of a fuel off-gas discharged from the fuel electrode, an oxidant off-gas discharged from the oxidant electrode, and a combustion exhaust gas discharged from the reformer;
• a hot water storage tank for storing stored hot water;
• a stored hot water circulation circuit for circulating the stored hot water, which exchanges heat with the condensing coolant circulating through the condensing coolant circulation circuit and the fuel cell heating medium circulating through the fuel cell heating medium circulation circuit;
• and
• a fuel gas heat exchanger which is disposed on the fuel cell heating medium circulation circuit, and in which the fuel cell heating medium and the fuel gas supplied to the fuel electrode exchange heat.