Seasonal Electricity Storage in the Form of Hydrogen Ready for Scaling

The project Underground Sun Storage 2030 (USS2030) has been successfully completed. It shows that Hydrogen can be safely stored and reused underground in large quantities - and over long periods of time. At the Rubensdorf/Gampern site, around 500,000 cubic meters of hydrogen were stored in a former natural gas reservoir. The hydrogen was recovered in high quality and can already be used today for CO₂-free electricity and heat generation. This is an important step towards the commercial use of this technology. The next tests will take place in a follow-up EU project. In addition, the “Seasonal Storage for Energy Communities” project is working with the municipality of Gampern to test its concrete use in everyday life. The project was funded as part of the “Vorzeigeregion Energie” of the Climate and Energy Fund, with funds from the Federal Ministry for Innovation, Mobility and Infrastructure (BMIMI). The project was managed by RAG Austria AG.

Summer electricity production in May already clearly shows that the peak production of solar energy, the associated low to negative prices and the competition between solar power production and hydropower require a suitable storage solution in order to operate economically viable renewable electricity production. Battery and pumped storage systems cannot take over and store these electricity volumes and outputs in the long term and on a large scale. In RAG's view, the only suitable technology solution that can bring the green surplus into the winter is power-to-gas and hydrogen as an energy carrier.

“With the completion of the last hydrogen storage cycle as part of the Underground Sun Storage 2030 project, a very successful project for RAG Austria AG is coming to an end. For the first time in the world, we have succeeded in demonstrating that large-volume storage in the form of pure hydrogen in gas reservoirs works in a real environment. This allows us to refute the claims that this storage technology is not technologically mature enough. I am also pleased that we can now continue operating the Rubensdorf / Gampern hydrogen storage facility directly as part of the “EUH2STARS” project. My thanks go to the entire team who made this achievement possible in the first place", as Stephan Bauer, Head of Green Gas Technology, commented on the project.

Ramp-Up of the Hydrogen Economy

Together with the project partners, RAG has mapped the entire value chain of the hydrogen economy on a demonstration scale. In addition to hydrogen production using electrolysis and storage, a hydrogen purification plant and pipeline infrastructure to a hydrogen consumer were also set up. In RAG's own hydrogen cogeneration plant, CO2-free electricity and CO2-free heat are produced from the stored hydrogen and used for the RAG site in Gampern.

“This good cooperation shows how it is possible to keep distances short and use regionally produced and stored energy directly on site. Seasonal storage thus contributes to the creation of a sustainable, regional and independent energy supply,” explains Jürgen Lachinger, Mayor of Gampern.

The EU Follow-Up Project “EUH2STARS”

The successful completion of the project forms the basis for the follow-up project, in which four further storage cycles will be carried out and feasibility studies on the scaling of hydrogen storage will be carried out. The aim is to develop market-ready storage solutions in underground sandstone Gas-bearing sandstone formations by 2030. If there is sufficient demand, the first storage facilities can be implemented in the short term. The industry-driven project is backed by a broad consortium and supported by the Clean Hydrogen Partnership as part of the EU's Horizon Europe funding program. The term ends in September 2029.