Energy generated from solar, and wind renewable sources are surging forward as contributors to achieving Net Zero. Hydrogen can be used as an energy carrier to store energy from renewable sources over a period (days to months) without generating any loss or pollution. It has been emerging as one of the leading options for future energy systems. However, the low volumetric density of hydrogen as well as the safety and economic issues associated with hydrogen storage inhibit its use as an economically viable energy vector. Among the existing routes, storage of hydrogen in the solid state as metal hydrides appears to be an attractive alternative both from the safety and the volumetric energy density points of view. It also offers high gravimetric capacity which potentially allows for storing enough hydrogen for distributed hydrogen demand. However, there are some issues with metal hydrides:

(1) The rates of hydrogen absorption and desorption are strongly controlled by heat and mass transfer; the thermodynamics and kinetics limits of these hydrides cause slow hydrogenation and dehydrogenation rates.

(2) The production cost of the solid hydrogen storage materials is still a major barrier to disabling scale-up for mobile or stationary applications. Metal alloys based on transition metals and rare earth elements are mostly studied, however, these significantly increase the material's cost. Lanthanum (La) has been widely used to alloy with other metals, but its price is approx. £300/kg.

(3) The lightweight, excellent heat resistivity and good recyclability, as well as abundant availability and low price make Mg Hydride a good candidate (the price of Mg is approx. £3/kg). However, the excessively strong chemical bonds result in the difficulty of releasing hydrogen, typically requiring high temperatures of 300-350oC to overcome the thermodynamic energy and kinetics barriers.

Addressing industry demand, key developments to cope with the above challenges will include improved energy efficiency and reduced production cost using low-cost and feasible chemical engineering solutions. Standard hydrogen sorbent modules will be developed using waste alloys and novel thermochemical energy storage (TES) which could suit multi-scale applications, particularly the heavy industry which has been widely recognised as a hard-to-decarbonize sector. It includes novelties in both hydrogen sorbent manufacturing using a 'template' method, emerging TES and induction heating, to synergistically improve the system efficiency and accelerate the dehydrogenation process, as well as the synergistic module. The success of this project will also contribute to the operating cost reduction of the solid hydrogen system and benefit researchers and engineers to accelerate hydrogen storage technology using abundant resources and low-cost technology.