The options include
- Storage in pressure vessels
Since the output pressure during electrolysis reaches up to 30 bar, it is often sufficient to store the gas in a pressure vessel without further compression. Only when storage capacity is not enough, compression to 200-300 bar or higher is required.
Pressure vessels are used for fuel cell vehicles where hydrogen is compressed to up to 700 bar.
- Feeding into the natural gas network
- Storage in caverns.
To store hydrogen in liquid form, it must be cooled to -253◦C. Special insulated cryotanks keep the gas at this temperature. These tanks are used in hydrogen-powered vehicles and in liquid tank trucks.
Metal hydride storage
This option profits from the good binding properties of hydrogen. Hydrogen molecules are chemically bonded within the metal compound structure and remain stable and nonhazardous at atmospheric pressure. Once the hydrogen is needed, the desorption process begins by feeding thermal heat (45 – 65°C) so gas begins to flow outward.
Hydrogen can be produced on-site (eg H2 refueling stations) through reforming or electrolysis which avoids further transport . Otherwise transport or distribution is required.
- Road Transportation
For road transportation of lower hydrogen volumes, special CGH2 (compressed gaseous hydrogen) trailers for compressed hydrogen and LH2 trailers for cryogenic liquefied hydrogen are used.
Transport of large amounts of hydrogen and over long distances are typically performed through pipeline networks.