The long-term vision of the ELOBIO project is the large-scale production of green hydrogen from renewable cellulosic biomass in fully integrated biorefineries with a circular bio-economy approach from the biomass supplier up to the final bio-products and green hydrogen. The ELOBIO consortium aims to answer the challenge “Novel routes to green hydrogen production” by advancing biomass electrolysis as a novel technological means of green H2 production. The project targets the assembly of a functional electrolyser capable of simultaneously producing pure green H2 and value-added decarbonized chemicals from renewable lignocellulosic biomass, including lignocellulosic from wood/forestry and residues from agriculture, with low energy input (technology transfer from TRL 1 to 4). These electrolysis cell prototypes comprise a selective cathode for the hydrogen evolution reaction (HER) and an anode capable of selectively oxidizing aldose-type sugars (xylose and glucose) and 5-hydroxymethylfurfural (5-HMF), which can be extracted after primary refining of the cellulosic material available from the abundant biomass feedstock worldwide. Combined, these molecules constitute an appropriate representative model to demonstrate the conceptual electrocatalytic valorization of biomass with cogeneration of pure green H2, with a view to extending it to a broader range of chemicals derived from lignocellulosic biomass treatment. Furthermore, critical materials such as platinum group metals, cobalt, or polymeric membranes are banned from consideration.