NOVELTY - The apparatus has first stainless steel cylinder (10) consisting of a stainless steel riser tube (11) and storing a reactant in a liquid water (16) with an overpressure of inert nitrogen gas (17). An outlet valve (21) is connected to an inlet valve (20) of a second stainless steel cylinder (18) containing solid sodium metal (22), through a mechanical pressure regulator (28) that senses and controls pressure of hydrogen gas (23) by injecting liquid water from the first into second steel cylinder, when the pressure above the metal drops below the pressure regulator set point pressure.    USE - Compact low cost chemical-mechanical apparatus for generating hydrogen gas to fuel cells for large scale on-demand application e.g. scientific research applications and industrial applications, to powering widespread commercial and private electric motor vehicle transport by a public.    ADVANTAGE - The apparatus allows the hydrogen gas generation by a controlled addition of liquid water to solid sodium metal to produce hydrogen gas and sodium hydroxide using only mechanical components without electrical components that require external power and to generate sparks or short circuits and producing catastrophic failure in hydrogen storage and generation systems. The apparatus allows the sodium hydroxide to be reclaimed and recycled by electrolysis using hydroelectric power to recover the sodium metal for reuse in generating hydrogen, thus forming a complete clean energy hydrogen power cycle. The apparatus allows a sodium hydroxide recycling plant in the second stainless steel cylinder to be refilled with sodium metal, and the first stainless steel cylinder is replenished with liquid water with an inert nitrogen gas over- pressure and made ready to be reinstalled in a commercial or private electric motor vehicle for continued operation delivering hydrogen gas to the electricity generating fuel cell. The apparatus allows for safely delivering hydrogen gas to fuel cells, and provides environmental cleanliness with a cost effective manner so as to well suit for large scale application to powering commercial and private motor vehicle transport. The apparatus allows street-T fittings to be connected to the stainless steel cylinders respectively and using pipe thread connections so as to prevent the possibility of nitrogen or hydrogen gas leaks effectively.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of chemical-mechanical apparatus for storing and generating hydrogen gas to power electricity generating fuel cells for commercial and private motor vehicle transport using the chemical reaction between water in the liquid state and solid sodium metal that releases hydrogen gas from the water and produces sodium hydroxide byproduct.    Stainless steel cylinders (10, 18)    Steel riser tube (11)    Liquid water (16)    Nitrogen gas (17)    Inlet valve (20)    Outlet valve (21)    Solid sodium metal (22)    Hydrogen gas (23)    Mechanical pressure regulator (28)