Geologic Hydrogen in Europe — Science, Exploration & Prospectivity

The science

Serpentinisation —
how the Earth makes hydrogen

Natural or geologic hydrogen is not extracted from chemical compounds — it is produced directly by geological reactions occurring continuously in the Earth's mantle and lower crust. The primary mechanism is serpentinisation: a set of exothermic reactions between iron- and magnesium-rich ultramafic rocks and water.

The serpentinisation reaction

When olivine- or pyroxene-rich peridotite rocks — the primary constituent of the Earth's upper mantle — come into contact with water at temperatures between 200°C and 400°C, a series of mineralogical reactions transform the rock into serpentine minerals while releasing molecular hydrogen:

Olivine + water → Serpentine + Magnetite + H₂

Fe₂SiO₄ + H₂O → Fe₃O₄ + SiO₂ + H₂

The key is the oxidation of ferrous iron (Fe²⁺) in olivine to ferric iron (Fe³⁺) in magnetite — a transfer of electrons that reduces water to molecular hydrogen. The reaction is exothermic: it releases heat and can be self-sustaining once initiated at the right temperature and pressure conditions.

Flux vs accumulation — the critical distinction

Not all natural hydrogen systems are economically equivalent. The crucial distinction, clarified by Christiansen et al. in Nature Communications (July 2026), is between active flux systems and structural accumulations.

An active flux represents continuous H₂ degassing from depth through fault zones — measurable at surface seeps. The Bulqizë ophiolite in Albania (200 t/yr at 84% purity) is the reference example. Production matches generation rate.

A structural accumulation is H₂ generated over geological timescales and trapped in a structural or stratigraphic seal — analogous to a conventional gas field. The Lorraine basin (PTH-2: 49.6% at 2,426m) is being investigated as a potential accumulation. This is the higher-value commercial target.

PoNHy (2026) provides the first open-source quantitative tool to distinguish between the two and assess generation rates in any geological system worldwide.

geological drilling borehole deep earth crust natural hydrogen serpentinisation exploration Europe

Deep geological drilling — the primary tool for natural hydrogen exploration at depth · PTH-2 (FDE, Lorraine) drilled to 3,655m · 49.6% H₂ measured at 2,426m · June 2026 · Photo: Unsplash (free to use)

Key geological facts

Temperature window — serpentinisation generates maximum H₂ between 200–400°C · above 400°C the reaction shifts and H₂ production decreases · this constrains the optimal depth range for exploration
Rock types — lherzolite and harzburgite (peridotite variants) are the primary source rocks · dunite less reactive · serpentinite (already reacted) produces little additional H₂
Generation rates — Christiansen et al. (Nature Communications, 2026): 0.1–0.5 t H₂/yr/km³ reactive rock · 300–600 t/yr per full serpentinising system · lower than earlier theoretical estimates
Trap conditions — commercial accumulations require exceptional geological seal (cap rock) and trap structure · marine shale or evaporite sequences are the most effective seals
Geological timescales — large accumulations require thousands to tens of thousands of years to build under favourable conditions · consistent with Lorraine's Hercynian basement context

European geology

European geological settings
most prospective for natural hydrogen

Europe's geological diversity — from the Hercynian basement of France, Belgium and Germany to the Alpine ophiolites of Switzerland and Italy, the Balkan ophiolites and the Iberian ultramafic belts — hosts a range of serpentinisation environments that the Getech/EC mapping programme (2026–2027) will systematically assess for the first time.

🇫🇷 France · NE Basin

Lorraine — Hercynian Basement

Sedimentary cover · Hercynian basement · lherzolite source?

The world's most advanced natural hydrogen exploration project. FDE's PTH-2 borehole: 49.6% H₂ at 2,426m (June 2026). REGALOR II independent certification expected 2027. Trois Évêchés permit: 2,254 km². Estimated 92 Mt deposit (FDE, not yet certified).

🇫🇷🇪🇸 France/Spain · Pyrenees

Western Pyrenees Ophiolites

Jurassic ophiolite · lherzolite · active serpentinisation

One of the two reference systems studied by Christiansen et al. (Nature Communications, 2026) using the PoNHy tool. Active serpentinisation documented. Hercynian basement shares geological heritage with Lorraine basin. H₂ surface seeps reported in multiple locations.

🇦🇱 Albania · Balkans

Bulqizë Ophiolite

Jurassic ophiolite · harzburgite · active flux system

The world's best-documented active natural H₂ flux system. Truche et al. (Science, Feb 2024): 200 t H₂/yr at 84% purity measured in the Bulqizë chromite mine. The reference example of an active flux system — distinct from Lorraine's accumulation model.

🇨🇭🇮🇹 Alps · Central Europe

Alpine Ophiolite Belt

Jurassic Tethyan ophiolite · lherzolite + harzburgite

The Alpine ophiolite belt stretching from the Swiss Valais through Northern Italy to the Adriatic hosts extensive serpentinised peridotite. Part of the Getech/EC 2026 mapping scope. Less explored for H₂ than Pyrenees or Balkans — geological potential not yet quantified with PoNHy methodology.

🇵🇹🇪🇸 Iberian Peninsula

Iberian Massif — Ultramafic Bodies

Variscan basement · peridotite massifs · Beni Bousera analogue

The Iberian Massif hosts several peridotite bodies (Ronda, Bragança, Morais) with documented serpentinisation. The Getech/EC mapping programme will include Iberian prospectivity assessment. Beni Bousera (Morocco) — a geological analogue — is one of the world's largest peridotite massifs.

🇧🇪🇩🇪 Belgium/Germany

Hercynian Basement — Ardennes/Eifel

Hercynian basement · shared with Lorraine · early-stage

The Hercynian basement underlying Belgium (Ardennes), Luxembourg and the German Eifel shares its geological heritage with the Lorraine basin. The BE.Hydrogen programme is mapping subsurface geology. No confirmed natural H₂ accumulation or flow on Belgian territory to date. Early exploration phase.

The Getech/EC Mapping Programme — July 2026

In July 2026, the European Commission's Directorate-General for Internal Market (DG GROW) awarded a contract of over €1M to Getech Group plc (Leeds, UK), in consortium with Trinomics B.V., to produce the first pan-European natural hydrogen prospectivity map.

The 12-month programme will assess all 27 EU member states using Getech's proprietary subsurface database and AI-driven pattern recognition, combined with the PoNHy open-source quantification framework published in Nature Communications (Christiansen et al., July 2026).

The output will be the first systematic comparison of natural hydrogen prospectivity across all European geological provinces — providing a scientific foundation for future exploration permitting decisions across the EU.

EU member states
assessed · Getech/EC
July 2026 → 2027
+€1M contract
DG GROW

Lorraine · The flagship project

PTH-2 and the Lorraine basin —
what the data shows

industrial energy production FDE Lorraine natural hydrogen PTH-2 borehole exploration production

From geological exploration to industrial production — the FDE value chain · PTH-2 confirmed · REGALOR II 2027 · production target late 2028 · Photo: Unsplash (free to use)

peridotite rock serpentinisation natural hydrogen geological formation Lorraine Pyrenees Hercynian

Peridotite — the iron-rich ultramafic rock at the heart of serpentinisation · the same rock type in the Pyrenees and Lorraine basement · Photo: Unsplash (free to use)

The PTH-2 results — June 2026

On 23 June 2026, Française de l'Énergie (FDE) published the results of its PTH-2 borehole at Pontpierre, Moselle — the world's deepest borehole drilled specifically to test for natural hydrogen at 3,655 metres total depth.

Key measurements: 36.1% H₂ at 2,242m and 49.6% H₂ at 2,426m in the formation fluid. The 49.6% concentration is among the highest ever measured in situ globally for natural geological hydrogen. The borehole intersected a basement zone that FDE believes corresponds to the source horizon identified in its REGALOR seismic survey.

FDE holds the Trois Évêchés exploration permit covering 2,254 km² in Moselle — the first natural hydrogen exploration permit ever issued in the European Union. Independent resource certification under the REGALOR II programme is expected in 2027.

The commercial case — if certified

FDE targets commercial production at €0.50/kg in late 2028 — approximately 6 to 12 times cheaper than current green hydrogen from electrolysis (€3–6/kg). At this price point, the economics of every synthetic fuel produced from natural hydrogen change fundamentally.

E-methanol would fall from ~€920/t to ~€280/t — below the price of fossil methanol, making FuelEU Maritime compliance commercially neutral. E-kerosene would fall from ~€2.50–3.50/L to ~€1.20/L — making ReFuelEU PtL mandates commercially self-sustaining without subsidy.

The critical milestone is REGALOR II certification in 2027. If the independent third-party assessment confirms the estimated 92 Mt deposit, Lorraine becomes the first European strategic natural hydrogen reserve — with implications for the entire European synthetic fuel supply chain.

"If the Lorraine deposit is confirmed at scale, it does not merely change the economics of one project — it changes the benchmark price of hydrogen for the entire European synthetic fuel industry."

geologichydrogen.eu · Editorial analysis · July 2026

PoNHy · Open-source tool · July 2026

The new standard for
natural hydrogen resource assessment

Published 21 July 2026 in Nature Communications (Christiansen et al., DOI: 10.1038/s41467-026-73920-5), PoNHy (Potential for Natural Hydrogen) is the first open-source, peer-reviewed Python framework for quantifying natural hydrogen generation potential in any serpentinising geological system.

geophysics gravity magnetic survey subsurface 3D inversion PoNHy natural hydrogen assessment

3D geophysical inversion — Module 1 of PoNHy · gravity + magnetic data → subsurface rock volume estimation · Photo: Unsplash (free to use)

thermodynamic modelling chemistry reaction temperature pressure natural hydrogen serpentinisation PoNHy

Thermodynamic modelling — Module 2 · H₂ generation rates vs temperature, pressure, lithology, fluid chemistry · Photo: Unsplash (free to use)

Monte Carlo simulation uncertainty quantification natural hydrogen resource assessment geological system

Monte Carlo simulation — Module 3 · 1,000s of parameter combinations → realistic rate ranges with confidence intervals · Photo: Unsplash (free to use)

What PoNHy provides — and what it found

Three integrated modules — 3D geophysical inversion (gravity + magnetic) · thermodynamic modelling · Monte Carlo uncertainty quantification · all open-source on GitHub (RodolfoChristiansen/PoNHy) and Zenodo (DOI: 10.5281/zenodo.18733249)
Generation rates — 0.1 to 0.5 t H₂/yr/km³ reactive rock in the Western Pyrenees and Northern California systems · 300–600 t/yr per full system · significantly lower than earlier theoretical estimates
Key limitation identified — H₂ saturation in pore fluid caps generation rate once saturation is reached · rapid large-scale reservoir replenishment is unlikely under current kinetic constraints
What this means for exploration — commercial accumulations require exceptional geological seal and trap conditions · the flux/accumulation distinction is critical · PoNHy helps prioritise drilling targets that are more likely to host structural accumulations
EU mapping application — the Getech/EC programme (27 member states, July 2026) will apply PoNHy as a standardised framework · enabling comparable prospectivity assessments across all European geological provinces

⚖️ Important Notice · Documentary Portal · Information Only

For information only: geologichydrogen.eu is a documentary portal of a strictly informational nature. All information comes from third-party public sources not controlled by BESS Energie SRL. No guarantee of accuracy, completeness or currency is given.

Consult primary sources: FDE (fde-corp.com / actusnews.com) · Christiansen et al., Nature Communications 2026 (DOI: 10.1038/s41467-026-73920-5) · Getech Group plc (getech.com) · EUR-Lex for EU regulations.

FDE's €0.50/kg target is a declared production objective, not yet independently certified. REGALOR II certification is expected in 2027. Belgium note: No natural hydrogen accumulation, flow or commercially exploitable resource has been confirmed on Belgian territory to date. BE.Hydrogen is a geological mapping programme — not a discovery. Not investment advice. © 2026 BESS Energie SRL · BCE 0698.949.732

Geologic hydrogenin Europe:the science, the geology,the projects

Serpentinisation —how the Earth makes hydrogen

European geological settingsmost prospective for natural hydrogen

The Getech/EC Mapping Programme — July 2026

PTH-2 and the Lorraine basin —what the data shows

The new standard fornatural hydrogen resource assessment

Geologic hydrogen
in Europe:
the science, the geology,
the projects

Serpentinisation —
how the Earth makes hydrogen

European geological settings
most prospective for natural hydrogen

PTH-2 and the Lorraine basin —
what the data shows

The new standard for
natural hydrogen resource assessment