NOVELTY - A geothermal power plant (15) produces power using geothermal fluid. The heat-depleted geothermal fluid exhausting or exiting the plant is supplied to a chemical reaction or electrolysis system (25). An indirect heat exchanger utilizes the heat in the geothermal fluid to produce hydrogen for use in producing power. The electrolysis-produced hydrogen and oxygen can be used to produce power or electricity. The pressure of these products can be used to operate a pump for re-injecting further heat-depleted geothermal fluid into a geothermal injection well (21).    USE - Apparatus for producing power using geothermal fluid from a geothermal power plant. Uses include but are not limited to a geothermal flash steam power plant, a geothermal steam power plant, an enhanced geothermal system power plant, a hot fractured rock power plant, and a hot dry rock power plant.    ADVANTAGE - The apparatus integrates geothermal and electrolysis plants into a combined geothermal cycle power plant. The efficiency of the combined plant is higher than the efficiencies of independently operated plants. The combined plant has flexible modes of operation during peak and off-peak demand hours. The electrolysis-produced hydrogen and oxygen act as energy storage vehicles. This feature enables the shift of off-peak geothermal power to be sold and consumed during periods of peak power demand. The local use of these products eliminates the need for high-pressure storage or transportation of these gases. The available pressure of these products can be used for other purposes. The efficiency of the electrolysis process is increased by heating the solution to be used in electrolysis with heat from geothermal fluid. Less electric power has to be used for heating the solution by using the pressure of the produced hydrogen and/or oxygen.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method for producing power using geothermal fluid.    DESCRIPTION OF DRAWING(S) - The drawing shows a conceptual block diagram of a combined geothermal cycle power plant for producing power and hydrogen and optionally oxygen for use in producing power.    Geothermal fluid source (11)    Geothermal power plant (15)    Geothermal injection well (21)    Chemical reaction or electrolysis system (25)