Patent attributes
The present invention provides a fuel cell power system and a power generating method in which the rise of concentration of water vapor and carbon dioxide in the direction of the anode gas flow is controlled to enhance the electromotive force in the downstream region of the anode gas flow, thereby improving the power generating efficiency. A mixed gas of a hydrocarbon and water vapor and/or carbon dioxide or a reformed version of said mixed gas having an oxygen atom/carbon atom ratio (O/C ratio) of 2 or higher is supplied from a spot upstream in the direction of the anode gas flow while a hydrocarbon or a mixed gas of a hydrocarbon and water vapor and/or carbon dioxide having an O/C ratio of lower than 2 is supplied supplementally from a spot downstream, and the gas supplied supplementally from the downstream side is reformed by making use of water vapor and carbon dioxide generated by the electrochemical reactions upstream of the anode gas flow and is utilized for power generation.