Storage, transport and use
Hydrogen can be stored even though its chemical-physical characteristics make it very complicated and expensive. The problem with hydrogen storage is particularly important since an efficient storage system in a co-production Plant of electricity and hydrogen, by decoupling the production phase from placement in the transport network, temporally allows optimization of the plant structure by appropriately splitting of electricity and hydrogen production processes based on the maximum economic returns.
Issues related to stationary storage relate mainly to the storage capacity, the storage energy flows and subsequent use of hydrogen and safety issues concerning the presence of large storage stations. In this context, the use of low pressure storage systems essentially based on hydrogen absorption in materials with chemical-physical hydrogen bonds with other substances forming hydrides and enabling good system compactness even at low pressures appear to be particularly interesting.
The activities carried out by RSE on this topic have concerned the definition of the most technology appropriate for low pressure hydrogen storage systems and the comparison between the properties of the different hydrogen storage systems for the purpose of orienting the storage solution in relation to the conditions of use.
Hydrogen storage systems of increasing capacity have been developed, based on metal hydrides (powders of metal alloys based on nickel, aluminum and lanthanum) and a storage unit was developed and subsequently coupled to a polymer electrolyte fuel cell. The activities of ongoing research in this field concern the verification of the potential of hydrogen storage prototype systems, by means of long-term experimentation; development and testing of magnesium hydride storage systems able to store 10 kg gas.