Underground storage facilities in Germany play an important role in balancing the daily and seasonal changes in natural gas consumption. Considering that Germany now has to import more than 90 % of its natural gas requirements, underground gas storage facilities are also an important strategic resource for securing gas supplies in Germany even in crisis situations. Crisis stockpiling of liquid hydrocarbons, such as gasoline and crude oil is even required by law under the Oil Stockpiling Act.
Natural gas is stored both in pore storage facilities and in cavern storage facilities; crude oil and other liquid hydrocarbons are stored exclusively in cavern storage facilities. Pore storage facilities are mostly sandstones from which natural gas was previously extracted. Caverns are cylindrical cavities in massive salt domes in Northern Germany, which were created by solution mining, i.e. dissolving the salt rock with the help of fresh water.
In the course of the energy transformation, the percentage of hydrogen, oxygen and carbon dioxide in the transport network is rising due to the increasing feed-in of biogas and hydrogen from renewable energies into the transmission network. For storage operation, these substances often pose additional technical challenges, for example in terms of microbiology or solution-precipitation reactions. This is where the DGMK Research in the specialist committee for underground storage technology comes in.