Infocenter

The European Commission has included Uniper Energy Storage’s two hydrogen storage projects - UST Hydrogen Storage Krummhörn and UST Hydrogen Storage Epe - on the list of “Projects of Common Interest” (PCI). This recognition highlights the strategic importance of these initiatives for supply security, grid stability, and the ramp-up of Europe’s hydrogen economy.

With PCI status, the projects benefit from accelerated permitting and planning procedures, improved European coordination, and the opportunity to apply for funding under the Connecting Europe Facility (CEF) program. 

This marks a decisive step toward realizing large-scale hydrogen storage in Germany and Europe.

Krummhörn: A Key Project for Northwestern Europe

According to the latest calculations, the UST Hydrogen Storage Krummhörn project foresees two salt caverns in its initial development phase, with a total H₂ working gas capacity of 430 GWh. The facility will be connected to Germany’s hydrogen core network and, in turn, to the planned European Hydrogen Backbone infrastructure, enabling cross-border hydrogen transport. The commissioning of the first cavern of approx. 200 GWh, is scheduled for the end of 2036, with the second cavern following later in the 2030s. The site offers a potential capacity of up to 2 TWh.

Epe: Flexibility and Security in the H₂ Corridor

At Epe - one of Europe’s largest energy storage clusters - Uniper Energy Storage is considering converting existing salt caverns currently used for natural gas storage to hydrogen. In the first expansion stage, two caverns with a working gas capacity of around 200 GWh could be operational by the end of the 2030s. The project strengthens regional resilience in North Rhine-Westphalia and provides seasonal and short-term flexibility for industrial customers locally and across Europe. Through planned integration into the European hydrogen network, Epe could become an essential component of a low-carbon energy supply in the future.

Strategic Importance for the Energy Transition

“The PCI status is a strong signal from Brussels: Europe’s hydrogen ramp-up will only succeed with high-performance storage,” emphasizes Doug Waters, Managing Director of Uniper Energy Storage. “Our projects in Krummhörn and Epe are key building blocks for a safe, secure, reliable, and flexible hydrogen supply. At the same time, one thing is clear: given the long lead time for storage projects then a stable financial and regulatory support model is needed otherwise no early investment decisions can be made.”

Inclusion in the PCI list underscores the role of hydrogen storage as the backbone of a functioning energy system. These facilities enable the storage of renewable hydrogen, balance grid fluctuations, and ensure continuous supply to industrial consumers - independent of generation volatility, such as during periods of low renewable output.

Both Uniper projects are still in an early development phase. However, Uniper is advancing project preparation to set critical milestones for long-term planning now. Current regulatory and economic conditions do not yet allow investment decisions, even though they are urgently needed given the long lead times of storage projects. The PCI status makes clear how hydrogen storage will become central to Europe’s energy infrastructure—as a key to supply security, flexibility, and a stable hydrogen economy.

In the 2025 reporting year, Uniper Energy Storage successfully met the increasingly ambitious targets for reducing methane emissions at its storage sites. All relevant emission sources were recorded using measurement methods of the highest quality levels (Level 4 and 5). For these achievements, Uniper Energy Storage was awarded the Gold Standard of the international Oil and Gas Methane Partnership 2.0 (OGMP 2.0) for the fifth consecutive time.

UST continues to pursue ambitious goals to further reduce its already very low methane emissions by 2030. The focus lies on the comprehensive detection of all significant emission sources using the most accurate methodologies (Level 5), as well as on implementing the requirements of the European Methane Regulation, which came into force in summer 2024.

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