NOVELTY - Hydrogen generated in the reaction chamber (50) passes through a separator (90) to separate the solids and liquids and delivers the gas through hydrogen outlet line (60). Inlet (80,100) and outlet (110) lines are connected to reaction chamber for supplying additional reagents or to remove reaction products. The dispensing of solid fuel to the reaction chamber containing the acidic reagents is controlled by monitoring and using the gas pressure in the system or reaction chamber. A controller (30) is included within the system to control the hydrogen generation system and the power module.    USE - For generating hydrogen in a fuel cell using acid catalyzed hydrolysis of a solid fuel.    ADVANTAGE - Effective energy density is increased by eliminating both the inherent concentration limit and the discrete catalyst bed which are present in liquid fuel based systems. Reaction chambers also function as heat-exchangers, hydrogen ballast tanks, and gas-liquid-solid separators to minimize balance-of-plant (BOP) and system complexity. Overall BOP is reduced since a discrete catalyst bed is not necessary. To maximize storage density, water to borohydride ion molar ratio approaching the room-temperature stoichiometric limit of 2:1 is utilized. When an acid solution is used in place of a solid heterogeneous catalyst system, the conjugate base of the acid is incorporated into the borate product to reduce the hydrated borate salts and water. Control of physical state, e.g. liquid or solid, of the reaction products is possible. Liquid reaction products enable easy removal of the reagents from the generator, while solids result in improved energy storage density due to the reduced need for excess water.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for    (1) method of generating hydrogen gas by hydrolysis reaction;    (2) method of operating a hydrogen device    DESCRIPTION OF DRAWING(S) - The drawing shows the schematic diagram of a hydrogen generator system with a solid fuel storage area, a solid fuel dispensing system, and a reaction chamber.    Controller (30)    Reaction chamber (50)    Hydrogen outlet line (60)    Separator (90)    Inlet lines (80,100)