Recipe For Finding Clean Natural Hydrogen May Change The Energy Game

For a fuel seen as critical to cleaner industry and energy, clean hydrogen supply has always been the hard part. New research suggests that Earth itself has already made far more hydrogen than society uses today, and that where it collects underground may no longer be a mystery.

Over the past billion years, geological reactions have produced hydrogen with energy equivalent to roughly 170,000 years of current global oil use, and some of that hydrogen is still stored in the continental crust.

>> In Other News: Researchers Discover Massive Hydrogen System Beneath the Pacific Ocean

“Recipe” For Finding Natural Hydrogen

Teams at the University of Oxford are trying to turn scattered hydrogen reports into a practical exploration recipe.

The work was led by Prof. Chris Ballentine, Department of Earth Sciences, University of Oxford in England. His research focuses on gases in rocks that can reveal where valuable fluids accumulate and how they escape.

By laying out the needed ingredients, the team gives companies a clearer way to search without wasting drilling budgets.

Modern farming depends on ammonia made from hydrogen, and that fertilizer supports about half the world’s food supply.

Most industrial hydrogen is stripped from natural gas or coal, and the heat and chemistry release carbon dioxide as waste.

That summary from the International Energy Agency ties 2022 hydrogen use to 992 million tons of carbon dioxide emissions.

One Net Zero Roadmap, an international climate pathway outlining how to reach net-zero emissions, puts 2050 demand near 584 million tons.

How Rocks Make Hydrogen

Deep underground reactions keep making natural hydrogen, but only two processes create most of it in continental rocks.

Water can react with iron-rich minerals in ultramafic rocks, deep-sourced rocks loaded with iron, and that oxidation releases hydrogen.

Other hydrogen forms when water splits through radiolysis, water broken apart by natural radioactivity, and the review explains where it happens.

Those reactions can run for thousands to hundreds of millions of years, so generation alone does not guarantee a drillable field.

Turning Hydrogen Into Energy

Hydrogen has to leave its source rock and move into spaces where enough hydrogen can collect.

Cracks, faults, and pores provide permeability, the ease that fluids travel, letting hydrogen flow upward with groundwater or as bubbles.

Because the molecule is small, it can slip through tiny openings, and helium in nearby fluids can flag shared pathways.

If the route crosses oxidizing rocks or active microbes, much of the hydrogen can vanish before it ever reaches a trap.

The cost of green hydrogen from renewable energy sources is expected to decrease by 2050 because of economy of scale and technology efficiencies. The cost and carbon footprint of natural hydrogen will be dependent on the production quality of the gas reservoir and hydrogen purity. The cost and carbon footprint of natural hydrogen would make it a highly competitive source of hydrogen. Credit: Nature Reviews Earth & Environment. Click image to enlarge.

Seals That Hold Hydrogen

A commercial discovery needs a pocket that holds hydrogen, not just a slow leak through open ground.

Hydrogen can pool when a porous layer meets a caprock, a tight layer that blocks hydrogen escape, and pressure builds.

Salt beds, dense clays, and even old lava flows can act as seals when later cracks do not cut through them.

Without a seal, hydrogen mixes into groundwater or vents to air, making extraction unsafe and uneconomical.

Where Hydrogen Gets Lost

Even in the right rocks, natural hydrogen can disappear if the subsurface hosts hungry biology or reactive minerals.

Many underground microbes use hydrogen for metabolism, the chemistry that powers cells, converting it into water or methane.

Other losses happen when hydrogen meets dissolved oxygen or metal oxides, and those reactions consume the hydrogen.

Exploration therefore favors settings with limited water circulation, low oxygen, and fewer microbes able to reach a growing hydrogen pocket.

Rocks That Repeat Worldwide

Several common regions put the ingredients close together, so the search is not confined to one continent.

Mountain belts can expose ophiolites, pieces of ocean crust pushed onto land, placing iron-rich rocks next to major faults.

Old continental granites can hold radiogenic elements, uranium and thorium that give off radiation, supporting hydrogen production over long times.

Because these settings occur in many countries, regulators and communities will need clear rules before companies start wide drilling.

Real Fields And Hard Limits

A few discoveries show that hydrogen can accumulate at high purity, but most regions still lack detailed measurements.

One field near Bourakebougou in Mali turned a 1987 water well into a case study for trapped hydrogen.

The review warns that continental systems do not recharge fast, so this supply should not be treated as renewable.

Researchers also argue that mantle hydrogen stays as water above about 56 miles depth, limiting that pathway.

Future Of Hydrogen Energy

Explorers can now screen regions for the full system, rather than chasing any hydrogen hint in isolation.

Field teams can combine gas sampling, groundwater chemistry, and careful mapping, then drill only where traps and seals align.

“One successful exploration recipe that is repeatable will unlock a commercially competitive, low-carbon hydrogen source that would significantly contribute to the energy transition. We have the right experience to combine these ingredients and find that recipe,” said Ballentine.

Careful well design will matter because hydrogen is highly flammable, and leaked hydrogen can threaten workers and nearby residents.

Taken together, the ingredients outline shows how Earth makes hydrogen, moves it, and sometimes locks it away for later use.

Industry still must prove sizable reserves and manage leaks, but a clearer search strategy could lower the cost of clean supply.

The study is published in Nature.