NOVELTY - The process for generating hydrogen useful as a fuel in vehicles such as automobiles, buses, trucks and motor homes, comprises oxidizing a metal component by reacting the component with water to form an oxidized metal, hydrogen and heat, and dehydrogenating a hydrogen containing compound by applying a portion of the heat to the compound to generate additional hydrogen. The generated hydrogen is proportional to water utilized in the oxidizing step. The metal component comprises metals and metal hydrides. The water is supplied in a form of steam in the oxidizing step.    USE - The process of generating hydrogen is useful as a fuel in vehicles such as automobiles or buses, and is useful for powering vehicles in conjunction with polymer electrolyte membrane fuel cells and/or modified hydrogen internal combustion engines.    ADVANTAGE - The process ensures effective, efficient, safe, economic and environmental friendly generation of hydrogen.    DETAILED DESCRIPTION - The process for generating hydrogen useful as a fuel in vehicles such as automobiles, buses, trucks and motor homes, comprises oxidizing a metal component by reacting the component with water to form an oxidized metal, hydrogen and heat, and dehydrogenating a hydrogen containing compound by applying a portion of the heat to the compound to generate additional hydrogen. The generated hydrogen is proportional to water utilized in the oxidizing step. The metal component comprises metals and metal hydrides. The water is supplied in a form of steam in the oxidizing step. The hydrogen containing compound comprises a metal hydride. INDEPENDENT CLAIMS are included for:    (1) a method for storing and generating hydrogen onboard a vehicle;    (2) a method for powering a vehicle; and    (3) a system for generating power using hydrogen.    DESCRIPTION OF DRAWING(S) - The diagram shows a schematic illustration of a system for generating power onboard a vehicle utilizing hydrogen.    Generator (4)    Water tank (6)    Gas cooler (16)    Hydrogen fuel cell system (18)    Radiator. (22)