Mantle8 Secures €31 Million Series A Funding for Natural Hydrogen Exploration

Mantle8, a Grenoble-based natural hydrogen exploration company, has secured €31 million in Series A funding, bringing its total funding to €37 million. The round was led by Sandwater and includes investors such as Breakthrough Energy Ventures, Ecotechnologies 2 fund (managed by Bpifrance on behalf of the French government), IP Group, Wind Capital, and Calderion.

Founded in 2019, Mantle8 aims to produce commercially viable natural hydrogen by 2030. The company has developed proprietary subsurface modelling technologies, including HOREX®, a multiphysics platform that creates 4D images of active underground hydrogen systems. Its exploration framework, the Geological Trifecta, identifies reservoirs where hydrogen-generating sources, continuous replenishment, and sealed reservoirs converge.

According to Mantle8, its technology reduces exploration risk and cost, with economic models projecting production costs as low as €0.80/kg. Over the next two years, the company plans to deploy capital to conduct exploration and drilling campaigns across its global development pipeline to confirm natural hydrogen accumulations and evaluate volume, purity, and reservoir quality.

In 2025, Mantle8 completed the world's first 4D imaging of an active underground natural hydrogen system at its Hydrogeco project in the French Pyrenees. Earlier this year, the company received a €2.06 million grant from the EU Just Transition Fund to industrialise its core exploration technologies.

Originally reported by Hydrogen Central. Read the full article →