Grand-rieu exploration license

Grand Rieu in brief

Bibliographical research and initial field studies were carried out in 2021 and 2022. This research, carried out as part of a research project called H2NA in which 45-8 ENERGY was involved, revealed a potential for native hydrogen in the Nouvelle-Aquitaine region.

In collaboration with Storengy, a subsidiary of the ENGIE Group, 45-8 ENERGY has applied for an exploration license covering an area of 266km² in the Pyrénées-Atlantiques Département (64) for a period of 5 years. 45-8 ENERGY is the operator of the project.

The aim of this application is to deepen our geological knowledge of the area and confirm its potential for native hydrogen.

A totally carbon-free resource, native hydrogen - also known as geological, natural or white hydrogen - could make a major contribution to the low-carbon hydrogen mix, particularly in the current context of the search for energy independence and decarbonization of industries.

Currently under review by the relevant authorities, the PER Grand-Rieu application represents an opportunity for the production and valorization of native hydrogen in south-western France.

The emergence of a native hydrogen industry in the French Pyrénées-Atlantiques region!


The exploration license

Bibliographic research and preliminary field studies have been carried out in 2021 and 2022, as part of the H2NA research project. Partly financed by the Nouvelle-Aquitaine Region, and in partnership with the French National Geological Survey (BRGM), UPPA (Université de Pau et des Pays de l’Adour), ENGIE, Storengy and CVA Group, the H2NA project studied the area’s potential for native hydrogen and defined the contours of an exploration license in a high-potential zone.

45-8 ENERGY, via its subsidiary 45-8 Grand Rieu, and Storengy have jointly filed a license application for a 266km² area in the Pyrénées-Atlantiques Département (64) with the French Ministry of Ecological Transition, which is currently being examined by the relevant authorities. The purpose of this application is to gain a deeper understanding of the geology of the area and confirm the potential for native hydrogen.

The granting of this exploration permit, and the subsequent validation of our hypotheses, would enable us to extract value from the native hydrogen and any associated gases. This potential production would encourage the use of hydrogen as a low-carbon energy carrier and contribute to the energy transition in south-western France.

The PER application has been submitted for a period of 5 years, in order to progressively acquire the necessary data to validate the hypotheses.

Exploration area size

0 km²

266 km²

Exploration area size




Valid period of the license
0 years

5 years

Valid period of the license


45-8 ENERGY and Storengy: a solid and unique partnership

The license application is being submitted jointly with ENGIE Group subsidiary Storengy, as part of a partnership that will enable both companies to leverage their respective expertise and resources.

45-8 ENERGY, through its subsidiary 45-8 Grand Rieu, is the project operator. It is coordinating all license activities and will be carrying out studies and works.

Storengy is a partner in the project. The company is contributing its technical skills to the studies and work to be carried out.


Storengy, an ENGIE subsidiary, is one of the world leaders in subsurface natural gas storage. The company has 21 natural gas storage sites in Germany and the UK. Storengy is also a key player in renewable gases. With 70 years' experience in subsurface exploration and exploitation, and in response to the current energy challenges of decarbonization and sovereignty, Storengy is today mobilizing its skills in the development of hydrogen storage infrastructures and the exploration of natural hydrogen with research and development projects initiated in 2016.

45-8 ENERGY and Storengy are collaborating on a second natural hydrogen exploration project in the French region called “Les Landes”. The application is currently being processed by the authorities.


The license goals

Identify the location of hydrogen-generating rocks and understand the migration path of hydrogen to the surface or to geological structures where it may have accumulated.

Precise characterization of the area’s geology and the zones most conducive to hydrogen accumulation.

Quantify the volumes of hydrogen that could be stored in the subsurface, and assess the technical and economic potential, all with the utmost respect for the environment.


The permit area

The license area covers 266km² and involves 36 municipalities in the French Pyrénées-Atlantiques Département :

Ainharp, Angous, Aren, Aroue-Ithorots-Olhaïby, Arrast-Larrebieu, Barcus, Berrogain-Laruns, Charre, Charritte-de-Bas, Chéraute, Dognen, Domezain-Berraute, Espès-Undurein, Esquiule, Géronce, Geüs-d’Oloron, Gurs, Jasses, Lay-Lamidou, Ledeuix, L’Hôpital-Saint-Blaize, Lohitzun-Oyhercq, Lucq-de-Béarn, Moncayolle-Larrory-Mendibieu, Moumour, Oloron-Sainte-Marie, Orin, Poey-d’Oloron, Préchacq-Navarrenx, Roquiague, Saint-Goin, Saucède, Sus, Verdets et Viodos-Abense-de-Bas.


The native hydrogen

The license application is exclusively for native hydrogen.

Is native hydrogen natural?

Native hydrogen is produced naturally in the subsurface. As such, its formation requires no critical materials, no anthropogenic energy and no impact on available fresh water resources.

How is hydrogen formed?

Native hydrogen is formed by the transformation of a rock from the earth’s mantle, reacting with water as it seeps through faults. This process, known as serpentinization, generates a rock called serpentine, as well as native hydrogen.

Is native hydrogen a carbon-free resource?

Yes, because it is produced naturally in the subsurface, native hydrogen is a totally carbon-free resource. Its production would therefore make it possible to envisage low-cost, low-carbon production to serve the energy transition of the south-west and of France as a whole.

Why produce native hydrogen?

Native hydrogen has a role to play in the decarbonization of industry and mobility. This type of hydrogen could easily be integrated into the existing low-carbon hydrogen mix as a natural, decarbonized and competitive resource.

Is it possibIe to find other gases?

Indeed, other resources could potentially be associated with native hydrogen. Helium, for example, could be associated! In the event that other resources are found, 45-8 ENERGY’s ambition is to exploit all subsurface resources.


The work program


The key steps of the license instruction

Application for an exploration license
Competitive bidding
Semester 1*
Public consultation
Semester 1*
Potential results of the instruction
2025 - 2029
If license obtained*
Geological synthesis and data acquisition

Theoretical dates. The steps to follow will depend on how long it takes to process the application with the authorities.

45-8 Grand-Rieu subsidiary

45-8 Grand-Rieu is 94% owned by 45-8 ENERGY.

Two other partners are taking part in the project for their expertise in the native hydrogen sector.

Lavoisier H2 Geoconsult

Lavoisier H2 Geoconsult

Lavoisier H2 Geoconsult SASU, is a geosciences research, consulting and services company established in 2022. Fueled by its research in geochemistry and working in association with a wide network of geoscience professionals, Lavoisier H2 Geoconsult develops, supplies and applies new methods for the exploration and evaluation of natural hydrogen reserves.

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M&U SASU is a geosciences research, consulting and services company dedicated to the exploration of strategic geo-resources for today and tomorrow. With a multi-disciplinary team combining Geology, Geophysics, Geochemistry and Numerical Simulation, M&U develops and applies innovative solutions to support its customers' Exploration in key energy and mining sectors worldwide. Designated a "Young Innovative Company", every day M&U identifies and develops research-industry synergies in the geosciences to address the climate crisis, the challenges of the energy transition and the need for new resources.

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