Exclusive interview with Olivier Delprat and Olivier Lhote from Storengy

In this opening edition of the FrHyGe newsletter, an exclusive interview is featured with Olivier Delprat, Project Coordinator, and Olivier Lhote, Technical Director of FrHyGe. They provide an overview of the project’s goals, focusing on its technical aspects and key innovations.

Our organization at Storengy, as leader of the consortium and project coordinator, is a duo with specific responsibilities.

  1. What is your role in the FrHyGe project, and what inspired you to take part in it?

O.Delprat: My role is the overall coordination, to lead the project towards its objectives, together with the Work Packages leaders, integrating the 17 members of the consortium and liaising with the Clean Hydrogen Partnership.

O.Lhote: Mine is to ensure that the partners have the necessary information to carry out their technical studies, that communication between the sub-projects takes place and keeping track of the critical tasks and their implementation. This also covers some methodologies and technical choices to be made, as well as external communication of objectives and project results.

  1. Can you outline the core goals of FrHyGe and its long-term impact on hydrogen storage in Europe?

O.Delprat: In the long run, the project aims at optimizing the whole energy value chain by integrating the innovation of large-scale underground storage (UHS), to better understand how renewable H2 can be supplied continuously to industrial, mobility, and other end-uses, while H2 production may be intermittent (daily or seasonally) due to renewable electricity.

FrHyGe’s main strategy is to unlock the potential of H2 storage in salt caverns, following a 3-phase sequence:

Phase 1: Focus on the Manosque demonstration site in France, for full qualification (TRL8) of the system from predefined conversion strategy.

Phase 2: Commercial up-scale of the Manosque site (TRL9) and know-how transfer for Germany uptake (SaltHy project).

Phase 3: Unlock EU replication from the technical conversion roadmap, along with risk and environmental assessment to feed the commercial exploitation strategy, in order to create a real European hydrogen storage backbone.

  1. What is the FrHyGe demonstrator, and how does it work to store hydrogen in salt caverns?

O.Lhote: The demonstrator consists of cycling 100t of hydrogen between two existing neighboring caverns (GA and GB) connected to each other to inject and withdraw the H2 back and forth.

A brine management system connecting the two caverns will be used to generate H2 flow between the caverns by pressure differential. The demonstrator also includes a gas treatment process skid in order to validate in industrial conditions all surface facilities aspects (purification, dehydration, metering, gas composition, and recompression).

The cycles will investigate various parameters (flow rate, flow durations in continuous and multicycling mode from hours to weeks, pressure, and gas dryness) in order to cover, in the most representative manner, all the possible future configurations and requirements.

Salt caverns are cavities in salt layers or domes artificially created by solution mining. They are excellent options for large-scale storage as there is already long experience storing hydrocarbons in caverns worldwide.
The salt is impermeable and inert, and hydrogen will be injected at high pressure (around 200 bars) in the cavern to store large quantities.

Hydrogen is withdrawn when required and stored again later with possible high injectivity and production rate.

  1. What makes FrHyGe unique compared to other hydrogen storage initiatives?

O.Delprat: The FrHyGe project is a large-scale demonstration of underground hydrogen storage (UHS), organized under an EU consortium, over a 5-year period from 2024 to 2028.

Project highlights:

  • EU consortium, gathering 17 partners from 4 different nationalities
  • Subsidy from the Clean Hydrogen Partnership (€20 million)
  • Feasibility of converting caverns from natural storage or brine to hydrogen storage
  • At least 100 H2 injection & withdrawal cycles at various pressures, rates, and volumes of 100 tons of hydrogen, a process not done before
  • Innovation that will bring TRL 7 to 8
  • Study of the local hydrogen value chain and the technico-economical impacts on local actors
  • Safety and environmental acceptability of commercial H2 storage in salt caverns
  • Replication potential towards other salt fields in the EU, starting with the SaltHy project in Germany
  1. How does the hyPSTER project complement FrHyGe, and what solutions has it provided so far?

O.Delprat: The FrHyGe demonstrator and the hyPSTER pilot project will allow Storengy and its partners to acquire experience and know-how, in order to prepare for the development, design, and realization of industrial-scale projects.

The hyPSTER project will provide test results by the end of 2024 or early 2025 (with 100-day duration hydrogen cycling tests in the EZ53 cavity, pressure variations through the brine compensation method). This may be followed by a technical and commercial operations phase in the coming years.

The results from the FrHyGe demonstrator will complement the hyPSTER pilot test results and deliverables in several areas (salt cavern conversion feasibility, project duration of 1 year, 100 cycles ranging from 1 hour to 1 week, higher H2 volume & variable flow, market assessment in France and Germany, permitting process, safety and environmental acceptability, commercial upscaling of the GeoH2 project at the Manosque site, and the replication of the SaltHy project in Germany).

O.Lhote: The simulation for 100 storage cycles, regardless of pressure, volume, or H2 quality constraints, will test a highly flexible environment and offer a better understanding of hydrogen storage and withdrawal in salt caverns under variable conditions related to intermittent production and fluctuating hydrogen demand.

  1. How does FrHyGe ensure sustainability and minimize environmental impact compared to other energy storage methods?

O.Lhote: Compared to other means of energy storage, underground hydrogen storage allows for a significant quantity of hydrogen to be stored (3000-7000t) with a low land footprint. Six underground pure hydrogen storage salt caverns are already in operation around the world, in the UK and the USA, used to provide feedstock for chemical production and to demonstrate the feasibility of safely storing hydrogen in salt caverns.

O.Delprat: Assessing the environmental impact, safety, and regulations of underground hydrogen storage are some of the priorities of the FrHyGe project in order to prepare for the deployment of industrial-scale projects.

Therefore, through the FrHyGe project’s WP5 – Environmental, Safety, and Regulatory Assessment, a series of concepts will be assessed and implemented, including major hazard risks, modelling worst-case incident scenarios, permitting and relations with competent authorities, lessons learned on safety, surveillance procedures, and life cycle analysis of underground hydrogen storage.