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European Partnership

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Clean Hydrogen Partnership

European Underground H2 STorAge Reference System

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 ( 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.