The first operating phase of the HyStorage project in Germany, with a 5 per cent hydrogen blend, was successfully completed. The partner companies Uniper, OGE, RAG Austria, Securing Energy for Europe (SEFE) and NAFTA presented the first interim results of the research project, which examines the integrity of porous rock formations for the storage of hydrogen.
“HyStorage is part of the implementation of Uniper’s Greener Gases strategy and serves to prepare commercial storage projects,” said Holger Kreetz, Uniper COO. “The storage of hydrogen in the Bavarian porous rock formations holds enormous potential for the flexibility of the emerging hydrogen market. However, an orderly transition and an integrated view of natural gas and hydrogen demand are required to ensure decarbonisation and a rapid hydrogen ramp-up while maintaining the security of natural gas supply with high-cost efficiency. Investments require a regulatory framework which should incentivise early investments. The principles of contracts for difference should be applied to achieve the aims in a cost-efficient and effective manner.”
“The initial preliminary results are generally optimistic,” emphasised Doug Waters, Managing Director of Uniper Energy Storage. “Although it is still too premature to make a definitive statement on the suitability of the southern German porous rock formations and thus the Alpine Molasse Basin in general, for pure hydrogen storage. But one thing is certain: hydrogen is becoming an essential element for the decarbonisation process of the European energy market. The existing underground storage facilities in Bavaria are of great importance for the security of natural gas supply in the coming years and, in the long term, for the transition to seasonal hydrogen storage with their large volumes and high injection and withdrawal rates. They provide a solution for the storage of volatile renewable energies and also for the connection to European hydrogen corridors.”
In particular, during the 7-day withdrawal phase, almost 90 per cent of the previously injected hydrogen was recovered. Analysis showed that the reservoir performance remained the same and a very homogeneous hydrogen distribution within the reservoir can be indicated.
The material testing has been successfully conducted and it showed no influence of hydrogen corrosion.
Also, the gas composition was analysed in detail at three points in the process to ensure the accuracy of the results and to guarantee safe operation.
Microbiological activities such as methanisation and sulfate reduction were observed on a small scale. In preparation for the test, a special hydrogen simulation model was developed solely for the HyStorage test that simulates hydrogen and natural gas flow in the reservoir as well as microbiological activity.
Additional steps are planned for the upcoming project phases to investigate whether the initial results remain valid for subsequent phases with higher concentrations and further exposure to hydrogen overall. Depending on further evaluation the second operating phase will be carried out this year.
Within the HyStorage project, three different natural gas and hydrogen gas mixtures with 5 per cent, 10 per cent and 25 per cent hydrogen content in the natural gas are injected into the former natural gas reservoir and then withdrawn after a three-month resting period in each case and blended into the station’s main field piping system. The first cycle with 5 per cent hydrogen serves as a basic check of the feasibility of the installations, the second will establish comparability with other international industrial projects and the third will be a continuation and preparation for future, higher hydrogen concentrations, but also for possible hydrogen peaks due to concentration fluctuations in the natural gas infrastructure.