Process for producing liquid hydrogen

Abstract

The invention relates to an integrated process for continuous production of liquid hydrogen, comprising (a) producing gaseous hydrogen by electrolysis; and (b) liquefying said gaseous hydrogen in a hydrogen liquefaction unit, which liquefaction unit is powered by energy essentially from renewable sources; and, (c) when additional power is needed, using electrical energy generated in a process in which electrical energy and hydrogen are co-generated by an integrated electrolysis process comprising: (d) electrolysing a metal salt or mixture of metal salts and water into the corresponding metal or metals, acid or acids, and oxygen (electricity storage phase), and (e) producing gaseous hydrogen and recovering electricity in a regeneration reaction of the metal (s) and acid(s) of step (d) (regeneration phase); wherein at least part of the gaseous hydrogen generated in step (e) is used in step (b) of the process.

Dependencies are inferred from the claim text.