Fraunhofer Institute for Mechanics of Materials IWMSalt caverns offer excellent conditions for storing very large quantities of green hydrogen from fluctuating renewable energies. As part of the joint basic research project H2-UGS, a standardized and transferable methodology was developed for the future construction and conversion of salt caverns for hydrogen storage.
H2-UGS: Accompanying research on the suitability of underground salt cavern gas storage facilities for the geological storage of hydrogen from fluctuating renewable sources
Completed research project
Project description
The aim of the H2-UGS consortium was to create the conditions for safe storage operation and to develop a methodology for regulatory approval issues relating to the storage integrity of hydrogen caverns. The topics addressed included degradation safety, geomechanics, microbiology, gas mixing, and plant design.
Fraunhofer IWM subproject: Degradation resistance of steel materials
Steels can be subject to hydrogen embrittlement, which manifests itself in reductions in various material properties. Therefore, the selection of a suitable steel material for use in underground hydrogen storage facilities is of particular importance. There are currently no standards or specific rules for the selection of materials for underground storage of hydrogen. Fraunhofer IWM is investigating the load limits of cavern piping and its weld seams. Weld seam areas can be more susceptible to hydrogen-induced damage than the base material due to structural changes and residual welding stresses. In the H2-UGS joint project, Fraunhofer IWM and its project partner SZMF developed investigation concepts for the corrosion resistance of materials for use in hydrogen and under sour gas conditions resulting from microbial processes in the caverns.
Transfer of project results to R&D services provided by Fraunhofer IWM
- Determination of quasi-static failure and cyclic fatigue limits of different pipe areas (base material, weld metal, heat-affected zone) using experimental and computational investigations, as certain relevant variables in the weld seam can only be determined experimentally with enormous effort.
- Calculation of the expected changes in load limits of the weld seams during operation of the cavern riser pipes based on characteristic values of the specific cavern, such as pressure, temperature, injection and withdrawal rates.
Funding information
