The overall aim of the project is to demonstrate underground hydrogen storage in depleted porous natural gas reservoirs at TRL-8. RAG Austria AG is in the unique position to start with an already existing pilot facility, developed within the framework of the USS-2030 project (www.uss-2030.at) to TRL 6. EUH2STARS will bring the pilot to TRL8 using results of several relevant projects (HyUSPRe, HyStoRIEs, Underground Sun Storage, Underground Sun Conversion and others). To achieve the overall aim and maximize the exploitation of the project results for replication in other regions of Europe the following specific objectives and outcomes are planned: - Provide recommendations to best manage all environmental, legal and (future) regulatory, societal and market-related aspects to ensure a successful implementation of an underground hydrogen storage facility in Europe (WP 1) - Provide recommendations on the topic of Health, Safety, Environment and Quality (HSEQ) including a monitoring plan to ensure an ALARP (as low as reasonably practicable) risk level when operating the demonstration site and future commercial storage sites (WP 2) - Run 4 cycles of seasonal operation with different characteristics and usage profiles to demonstrate the ability to integrate with different energy infrastructure systems with highest purification levels of Hydrogen (WP 3) - Show transformation pathways to replicate demonstrator findings in full-scale commercial settings at existing underground gas storage facilities and new to be developed storage sites in depleted natural gas reservoirs in Europe located in Austria (RAG), The Netherlands (Shell), Hungary (HGS), and Spain (TES) (WP 4) - Show how to integrate hydrogen storage facilities into the local, national and European energy infrastructure and market by showcasing specific use cases in AT, HU, NL and ES and other use cases including the integration into the European Hydrogen Backbone (WP 5) - Establish a sound interactive stakeholder involvement process to maxim replication potential and exploitation of the demonstrator results (WP 6). Our EUH2STARS mission is: Best practice demonstrator for a competitive, complete and qualified large-scale hydrogen storage system using a porous subsurface reservoir to enable the integration of European renewable energy sources.

The HI2 Valley project will establish a large-scale renewable hydrogen (H2) economy in the Austrian industrial regions of Upper Austria, Styria and Carinthia, directly contributing to the goals outlined in the European Green Deal, REPower EU and Hydrogen Strategy. The project will achieve this by decarbonising key sectors through H2, drastically reducing emissions in the steel, chemical, and cement industries as well as in energy and mobility via displacement of fossil fuels – including reducing the reliance on natural gas which Austria overwhelmingly imports from Russia. With 13,000 tons of green hydrogen being needed in the regions by 2028, over 10,000 tpy of green hydrogen will be produced within this HI2 Valley. By introducing strategically placed, decentralised H2 production facilities, the project will strengthen the country's energy resilience and flexibility and create a robust domestic market for green H2. The HI2 Valley will play a crucial role in bridging the gap between Southern and Eastern European hydrogen supply corridors. Being embedded on the European Hydrogen Backbone and TEN-T network and future pipeline connections (PCIs) with Southern Europe and North Africa, the HI2 Valley will seamlessly connect Austria's multi-user H2 ecosystem with neighbouring countries like Germany, Italy and Slovakia, fostering a truly interconnected Central European hydrogen network. This role model helps to secure industrial jobs, and through standardisation and integration brings costs of hydrogen down, creating a green industrial future for Europe. Going beyond its immediate neighbours, the HI2 Valley will also foster knowledge sharing and wider adoption of green hydrogen through the active collaboration with five other emerging Hydrogen Valleys in Eastern Europe in Poland, Romania, Hungary, Latvia and the Czech Republic.