Grand-rieu exploration license
The emergence of a native hydrogen industry in the French Pyrénées-Atlantiques region!
01
The exploration license
Bibliographic research and preliminary field studies are being carried out between 2021 and 2022, as part of a research project called H2NA. Co-financed by the Nouvelle-Aquitaine Region and academic and industrial partners such as 45-8 ENERGY, BRGM, CVA Group, ENGIE, UPPA and Storengy, the H2NA project confirmed the area’s potential for natural hydrogen and defined the contours of an exploration license in a high-potential zone.
In March 2025, 45-8 ENERGY and Storengy obtained the “Grand Rieu” exploration license for an area of 266 km² in the Pyrénées-Atlantiques department for a period of 5 years. Granted by the French Ministry of Ecological Transition, this license aims to deepen geological knowledge of the area and confirm its natural hydrogen potential.
The perimeter chosen for this application is deliberately vast, in order to gain a global understanding of the geology of the area, and then to target high-potential zones as data is acquired.
If our hypotheses are validated, we envisage the joint development of natural hydrogen and any associated gases. Such production would encourage the use of hydrogen as a low-carbon energy source, and contribute to the energy transition in the south-west of France.
Exploration area size
266 km²
Exploration area size
36
Municipalities
5 years
Valid period of the license
02
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.
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.
03
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.
04
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.
05
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.
06
The work program
07
The key steps of the license instruction
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
M&U
