NOVELTY - The anode circuit has a recirculation conveying device (16) for anode gas exhaust, which is drivable by an air driven power turbine (17). The recirculation conveying device is provided in the form of a gas jet pump (11) by which the fuel flowing to the fuel cell (3) is driven as a propellant gas stream. The recirculation conveying device is connected with the power turbine through a clutch (19). The clutch comprises magnetic coupling and freewheel. The power turbine is driven by the cathode-side airflow to and/or from the fuel cell.    USE - Anode circuit of fuel cell system mounted in vehicle.    ADVANTAGE - The small, compact and energy-efficient fuel cell system can be obtained. The enhanced energy balance of the fuel cell system is enabled and the energy is saved in the region of air supply. The cathode-side air conveying device of the fuel cell system is smaller and more efficiently formed. The recirculation conveying device with the drive turbine is formed as free runners which is simple and efficient. The simple, inexpensive and very sturdy recirculation conveying device can be obtained without supplementary control and/or drive device. The product water from the atmospheric oxygen and fuel, freezes as high-purity water very easily, when freezing cross sections of a line to clog. The recirculation conveying device is driven by air driven power turbine simply and efficiently so that the flushing of the anode side of the fuel cell can be realized efficiently. The regular operation of the fuel cell system is performed energy-efficiently with small power consumption. The fast and efficient heating of the recirculation conveying device can take place, so that quick start of the fuel cell system is enabled.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for method for operating fuel cell system.    DESCRIPTION OF DRAWING(S) - The drawings show the schematic view of the fuel cell system with anode circuit.    Fuel cell (3)    Gas jet pump (11)    Recirculation conveying device (16)    Power turbine (17)    Clutch (19)