“Nouvelle-Aquitaine” Region : The birth of natural hydrogen exploration in France ?

As a pioneer, 45-8 ENERGY focuses on exploring and producing eco-responsible industrial gases: helium and natural hydrogen. , as well as the resources that can be associated with.Hydrogen is an energy carrier with a very low carbon footprint, produced naturally via geological processes without the need for critical resources such as pure water. It is economically competitive due to low operating costs, three times more energetic than oil, and its combustion produces only energy and water.Committed to energy and ecological transition, 45-8 ENERGY aims to produce hydrogen and its associated resources as close as possible to the European consumers.Being convinced that “Nouvelle-Aquitaine” region is a favorable area for the natural hydrogen generation in subsurface, its subsidiary, 45-8 GRAND RIEU, partnered with Storengy (an Engie affiliate) to apply for two exploration licenses in 2023, likely to be awarded in 2025. Each five-year license aims to:Map rocks capable of generating hydrogen and predict migration paths. Identify potential reservoir and seal formations for trapping hydrogen. Quantify potentially accumulated hydrogen volumes and evaluate production feasibility. Decide on drilling exploratory wells based on findings. Upfront of these applications, Nouvelle-Aquitaine has been hosting the H2NA research project since 2021, led by 45-8 ENERGY, CVA Group, BRGM, UPPA, ENGIE, and Storengy, under pôle AVENIA. This multidisciplinary initiative evaluates the region’s natural hydrogen potential to encourage exploration license applications and focus research on promising hotspots. Its success is evidenced by the application for three licenses.In April 2022, the inclusion of natural hydrogen in France’s Mining Code encouraged companies to explore this emerging resource. The region’s geological suitability stems from the serpentinization process, where ultrabasic rocks oxidize in the presence of water, generating hydrogen and hyperalkaline fluids. The uplifted mantle wedge in the Western Pyrenees, at “shallow” depths (8-10 km), is ideal for this process due to favorable temperature and pressure conditions. Indicators like positive magnetic anomalies, Bouguer gravity anomalies, and high seismic velocities further support hydrogen generation potential.The Arbailles Massif karst system in the southwest facilitates meteoric water infiltration, which reaches the mantle wedge through Pyrenean faults. Generated hydrogen may migrate vertically to subsurface traps or laterally along faults like the North Pyrenean Fault (NPF). This explains anomalies in hydrogen, radon, and CO2 concentrations in soil gases in the Mauléon Basin, correlating with major regional faults.While the Aquitaine Basin north of the NPF has been extensively analyzed since the 1950s, the southern region remains underexplored due to overmature hydrocarbon source rocks. However, structural traps and reservoir-seal systems make this area highly promising for hydrogen exploration. Tools like 45-8 ENERGY’s SurfMogH2 geochemical probe can monitor hydrogen seeps over time, aiding exploration.Hydrogen plays a crucial role in ecological transition and decarbonization goals. Its ability to store and release energy supports renewable energy development, decarbonizes heavy mobility, and serves industries consuming large hydrogen quantities, like the Lacq basin’s petrochemical sector. Numerous low-carbon hydrogen projects are underway in Nouvelle-Aquitaine, with regional and trans-Pyrenean coordination fostering the energy transition.