NOVELTY - An anode utilization control system comprises an oxygen sensor secured in fluid communication with a burner exhaust for sensing a concentration of oxygen within the burned anode exhaust stream passing out of the burner device through the burner exhaust; and an oxygen sensor controller (80) secured in communication between the oxygen sensor and a fuel flow control device secured in fluid communication with the fuel feedstock inlet line.    USE - An anode utilization control system for a fuel cell power plant for generating electrical current from an oxidant stream and a hydrogen-rich fuel stream for use in transportation vehicles, portable power plants, or as stationary power plants.    ADVANTAGE - The system is cheap, and can control anode utilization during steady-state operation of the plant as well as during electrical current transients resulting from various types of disturbances.    DETAILED DESCRIPTION - An anode utilization control system comprises:    (A) fuel cell(s) including an anode catalyst (14) and a cathode catalyst (16) secured to opposed sides of an electrolyte (18), an anode flow field defined in fluid communication with the anode catalyst and with a fuel inlet line for directing flow of the hydrogen-rich fuel stream from the fuel inlet line adjacent the anode catalyst and out of the anode flow field through an anode exhaust (24) as an anode exhaust stream, a cathode flow field defined in fluid communication with the cathode catalyst and with a source of the oxidant for directing flow of the oxidant stream from an oxidant inlet line adjacent the cathode catalyst and out of the cathode flow field;    (B) a fuel processing system for generating the hydrogen-rich fuel stream from a fuel feedstock, and including a burner device secured in fluid communication with the anode exhaust and secured in heat transfer relationship with an endothermic reacting reformer, transfer line secured in fluid communication with the anode exhaust stream burned within the burner device or by burning the anode exhaust stream within the burner device to generate steam within a boiler secured adjacent the burner device and directing the steam through a steam transfer line into the reformer that is secured in fluid communication with the heat transfer line or the steam transfer line;    (C) a burner feed line secured in fluid communication between the burner device and the anode exhaust for directing the anode exhaust stream into the burner device to be burned and out of the burner device through a burner exhaust;    (D) an oxygen sensor secured in fluid communication with the burner exhaust for sensing a concentration of oxygen within the burned anode exhaust stream passing out of the burner device through the burner exhaust; and    (E) an oxygen sensor controller (80) secured in communication between the oxygen sensor and a fuel flow control device secured in fluid communication with the fuel feedstock inlet line.    The burner device is configured to transmit heat to the reformer by transmitting heat directly into the reformer through conduction and convection through a heat. The reformer is secured in fluid communication with a fuel feedstock inlet line for directing the fuel feedstock into the reformer to be reformed into the hydrogen-rich fuel stream, and being secured in fluid communication with the fuel inlet line for directing the reformed hydrogen-rich fuel stream through the fuel inlet line into the fuel cell. The oxygen sensor controller is configured to selectively control flow the fuel feedstock through the flow control device into the reformer in response to sensed oxygen concentrations within the burned anode exhaust stream. An INDEPENDENT CLAIM is included for a method of controlling anode utilization in a fuel cell power plant.    DESCRIPTION OF DRAWING(S) - The drawing is a schematic view of a utilization control system.    Anode catalyst (14)    Cathode catalyst (16)    Electrolyte (18)    Anode exhaust (24)    Oxygen sensor controller (80)