Abstract: An apparatus for producing hydrogen may include a collector of radiation to concentrate solar radiation on a converter having an absorptivity to convert the solar radiation to thermal energy to drive a chemical process using a feedstock to dissociate into an output chemical and a byproduct. A separator separates the output and byproduct, after which a reactor reacts the output to form a storage chemical, reactive to produce energy but sufficiently stable for safe handling outside designation as an energetic material. The separator may have a porosity to substantially pass hydrogen and block oxygen and water. A sweep gas may sweep hydrogen away from the separation barrier to change equilibrium. Catalysts may reduce temperature of dissociation and a subsequent reaction to combine it in a more stable, storable form.