Hydrogen is the universe’s oldest and most abundant element. The clean energy discussion has centered on “green hydrogen”—manufacturing it using renewable electricity.

But what if the earth itself held vast, untapped reserves of pure, naturally occurring hydrogen, ready for us to tap into?

In this week’s podcast I speak to Emmanuel Masini, known as Manu, a geologist and the CEO of Mantle8, a company at the forefront of exploring this game-changing resource. The company is backed by Bill Gates’ Breakthrough Energy Ventures and Kiko Ventures.

We discuss how natural hydrogen is formed in the earth’s crust, and what conditions need to exist to find pure natural hydrogen.

Manu explains what he calls the “geological trifecta” that is needed for economic natural hydrogen extraction.

Extraction of natural hydrogen could overcome the cost barriers of green hydrogen production, which remains much higher than hydrogen produced from fossil fuels.

Mantle8 is targeting a production cost of less than one euro per kilogram, compared to between 5 to 7 euros for green hydrogen produced from renewable sources of electricity.

Currently the only producing natural hydrogen well is in Mali, but it only produces around 5 tonnes a year.