TECHNOLOGY FOCUS - MECHANICAL ENGINEERING - Preferred Component: At least one fuel container contains chemical hydride(s), reactive solids or volatile reactants. Walls of the fuel containers are permeable to the volatile reactant(s). A reaction control mechanism is included adjacent the container for regulating mass flow rate of reactants between containers. An adjuster is connected to the container, where fuel diffusion from container(s) is adjusted electrically or mechanically. The hydrogen gas is filtered through filter. A mass flow conduit conducts a mass flow back to the containers from a consuming device.Each fuel bearing container comprises two or more types of fuel ampules (8, 12), which, when used, are removed from fuel impermeable containers and placed in proximity to the other type of fuel ampule and a fuel cell. A cover is replaced to form a fuel diffusion plenum having a fuel and restricting air exchange with the plenum. Products (91), water, or carbon dioxide from a hydrogen consuming device react with fuel in the container for supplementing or intensifying hydrogen production reaction between the fuel. Additives are included in the ampules to change appearance of the ampules and indicate fuel quantity.    TECHNOLOGY FOCUS - POLYMERS - Preferred Material: The walls of the fuel containers are made of silicone rubber or polymers that exhibit low permeability to water and high relative permeability to methanol, formaldehyde, carbon dioxide, acetic acid, or formic acid. The filter is a hydrogen permeable polymer.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Component: The chemical hydrides (11) are lithium hydroxide, lithium aluminum hydride, lithium borohydride, sodium hydride, sodium aluminum hydride, sodium borohydride, magnesium hydride, magnesium borohydride, potassium hydride, potassium borohydride, calcium hydride, or calcium borohydride. One fuel container contains lithium, sodium, potassium, rubidium, aluminum, or calcium. The hydrogen-bearing fuel is a hydrogen gas (21) used in a fuel cell (90). The filter is a hydrogen permeable metal film.