Storage of pressurised gas

We talk of the storage of pressurised gas whenever a gas is stored under higher than normal pressure. Tanks for the storage of pressurized gas differ by their construction according to the type of application which determine the required pressure levels. For the most part stationary tanks have a lower pressure level because this type of storage is cheaper. The requirements for mobile applications, for example in a motor vehicle, are quite different because there is not much room for tanks. For such applications tank pressure is increased up to 70 MPa (700 bar) in order to store as much hydrogen as possible in a very confined space.

Pressure tanks used to be made from steel and therefore were very heavy. Modern pressure tanks are made from composite materials (coal-fibre composite materials with a thin internal aluminium liner) and they are much lighter.

When it is necessary to store large amounts of hydrogen in a future energy economy then hydrogen can be pressed into subterranean cavern storages. There it can be stored under a pressure of up to 5 MPa (50 bar). In France and in the USA this method is already in use. In Germany natural gas is stored in such caverns. They could be used for the storage of hydrogen in future.

Vehicle storage system (GM)

Storage system for buses (roof system by MAN)

Stationary storage system at a filling station