This development marks the start of the second project phase, H2CAST Build, which follows the successful completion of H2CAST Ready, a preparatory phase focused on verifying the caverns’ suitability for hydrogen storage. In parallel, construction of the associated above-ground facility has commenced.
The project aims to demonstrate the feasibility of large-scale underground hydrogen storage and support the development of a flexible facility with a total capacity of up to 1 TWh. The cavern storage site in Etzel is strategically located near the German-Dutch hydrogen market, with strong links to the planned hydrogen core network and the Energy Hub in Wilhelmshaven.
In the Netherlands, Gasunie has now started developing underground hydrogen storage facilities in the northern part of the country (HyStock). In Etzel, Gasunie and Storag Etzel have been working together since 2023 on the H2CAST pilot project, a trial to prove the feasibility of storing hydrogen in two existing, immense caverns with a geometric volume of around 300,000 cubic metres.
Marc van der Linden, Business Development Director of Gasunie, commented: “Hydrogen will play an important role in the future energy system, especially in making industry more sustainable. Large-scale hydrogen storage is crucial for an efficiently functioning hydrogen market. For Gasunie, these milestones are the next step in its ambition to develop hydrogen storage capacity in order to help ensure a smooth start of the hydrogen market in the Netherlands and Germany,” said Marc van der Linden, Business Development Director of Gasunie.
Boris Richter, Managing Director of Storag Etzel, said: “H2CAST is a research project to test underground storage in caverns on an industrial scale. The H2CAST project will generate important information as a blueprint for the conversion of further caverns for hydrogen storage in Germany and help us gain valuable operating experience in this area.
“The Etzel site already operates as an energy hub with an existing connection to the European natural gas grid. Etzel is also located in the immediate vicinity of Germany’s only deep-water port in Wilhelmshaven. This port has H2-capable pipeline connections and will also play an important role in the H2 core network for hydrogen imports in the future.
“We are working continuously on our hydrogen storage strategy. The Etzel caverns are flexibly scalable so that existing local underground gas and oil storage facilities can also be repurposed for hydrogen. So there are various options for expanding the project in the future. One thing is certain: underground storage of hydrogen in caverns on an industrial scale works effectively. We will be ready when the H2 market materialises.”
