The aim of this work package is to carry out in-situ tests on the storage of hydrogen in depleted natural gas deposits at the facility that was built as part of WP8. These in-situ tests are unique in the world and are being carried out for the first time as part of the Underground Sun Storage 2030 project. The storage of renewable energy in the form of hydrogen will be carried out in a small isolated depleted natural gas reservoir about 1,000 m below ground level. Through numerous measurements and observations, we want to gain knowledge about the behaviour of the hydrogen during storage. After extraction, the hydrogen will be dried and further treated for testing purposes in order to prove that this hydrogen can also meet the high quality requirements for use in fuel cells. In total, two seasonal storage cycles are planned within the framework of this project.
