NOVELTY - The power supply system comprises a chemical reaction section (100) comprising an evaporation section (103, 112, 114) and a reaction section (107) comprising a reform section and a carbon monoxide removal section (105). The reform section receives a gas mixture of the fuel and the evaporated steam to produce hydrogen-containing reformed gas. The carbon monoxide removal section (105) for removing carbon monoxide contained in the reformed gas to produce power generation gas. The system is formed as a module removably fitted to the load.    USE - Used in power units of mobile equipment and electric automobiles.    ADVANTAGE - Cost effective power supply system has high power generation capacity and suppresses a rise of carbon monoxide concentration to protect human body.    DETAILED DESCRIPTION - The power supply system comprises a chemical reaction section (100) comprising an evaporation section (103, 112, 114) and a reaction section (107) comprising a reform section and a carbon monoxide removal section (105). The reform section receives a gas mixture of the fuel and the evaporated steam to produce hydrogen-containing reformed gas. The carbon monoxide removal section for removing carbon monoxide contained in the reformed gas to produce power generation gas. The system is formed as a module removably fitted to the load. The reaction section generates a power generation gas based on steam generated by the evaporation section and the liquid/gas fuel containing hydrogen. A power generation section (120) receives the power generation gas, and generates power for driving a load of an electronic apparatus by an electrochemical reaction. The evaporation section receives liquid/gas power generation fuel and water supplied from fuel and water supply sections, and evaporates the water by heating. A temperature detection section is further used for detecting temperature of the evaporation section. A control section (130) controls the system operation by stopping the fuel supply when the evaporation section has lesser detected temperature than boiling point of the water. The evaporation section comprises two sections for individual evaporation of the fuel and the water, and a mixer (115). The mixer mixes the steam and the evaporated fuel, and supplies the mixture to the reaction section. An output detection section is used for detecting power from the power generation section. The power generation section controls operation of all the sections in the system partly integrally formed with the load. A fuel containing section (140, 160, 804) contains power generation fuel in sealed condition. An INDEPENDENT CLAIM is included for a method of controlling a power supply system.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic block diagram of a power supply system:    Chemical reaction section; (100)    Evaporation section; (103, 112, 114)    Carbon monoxide removal section; (105)    Reaction section; (107)    Mixer; (115)    Power generation section; (120)    Control section; (130)    Fuel containing section. (140, 160, 804)