Nearly 15,000 boreholes at a copper mine in northern Ontario are releasing more than 140 metric tons of natural hydrogen a year, and researchers confirmed the flow has not slowed in over a decade
Somewhere below the boreal forest of northern Ontario, a mine built to pull copper from the ground has been doing something else entirely.
For more than a decade, nearly 15,000 holes drilled into the rock walls have been exhaling hydrogen.
No machine was making it.
No electrolysis rig, no steam reformer, no megawatt diverted from the grid, the rock itself was producing it, the way it has for hundreds of millions of years.
No electrolysis rig, no steam reformer, no megawatt diverted from the grid, the rock itself was producing it, the way it has for hundreds of millions of years.
Until a paper landed in a leading science journal this past spring, nobody had measured how much. How does ancient stone keep generating a clean fuel without any help?
What billion year old rock does to water
Deep in the Canadian Shield, iron rich Precambrian rock reacts with groundwater in a slow chemical process called serpentinization, where iron in the stone steals oxygen from water molecules and leaves pure hydrogen gas behind. The same reaction occurs along mid ocean ridges and inside the mantles of Mars and the Moon, but the Shield concentrates it unusually well because the rock is ancient, cold, fractured and isolated from the surface.
Because the fracture networks are sealed by vast pressure, the gas builds steadily rather than dispersing. When a mining crew drills a borehole, it opens a small window in that sealed system and the hydrogen flows out. Some boreholes at the Ontario site have been releasing gas for 11 years without measurable decline, a sustained duration that separates this find from a laboratory curiosity and pushes it toward something engineers may eventually call a resource.
The mine near Timmins that nobody was watching for this
Geochemists spent years tracking the gas at a copper and zinc mine near Timmins, Ontario, where sampled boreholes sit between 6,800 and 7,850 feet underground. The mine is one of the world’s deepest base metal operations, opened in the 1960s to extract copper, zinc and silver from one of the richest ore bodies ever found. It was never designed as an energy site.
The boreholes were drilled for geological and structural reasons, not for fuel. Researchers found that each releases an average of about 17.6 pounds of hydrogen per year, and extrapolating across nearly 15,000 boreholes gives a total discharge of more than 140 metric tons per year, enough to generate roughly 4.7 million kWh of energy annually.
The first time the numbers were actually written down
Researchers at two Canadian universities measured, mapped and tracked the sustained discharge of natural hydrogen, sometimes called white hydrogen, within the ancient rocks of the Canadian Shield. Their findings were published in May 2026 in the Proceedings of the National Academy of Sciences, representing the first documented sustained flow of this gas from continental hard rock over a period of years.
The lead researcher put the geological logic plainly, saying that natural hydrogen is produced through underground chemical reactions between rocks and the groundwaters in those rocks, and that Canada’s vast territories on the Canadian Shield contain the right rocks and minerals to create it. The largest concentrations appear in geological regions already tied to Canadian mining activity, including northern Ontario, Quebec, Nunavut and the Northwest Territories. The same rock runs under Minnesota, Michigan and New York, though the paper leaves open whether those formations produce comparable flows, because the measurements came from one site.
The catch that keeps this from being a simple solution
The specific rock chemistry, fracture systems and groundwater conditions that produce natural hydrogen vary site by site. The 140 metric ton figure is extrapolated from per borehole averages across one mine, broadly in line with what has been reported for a separate site in Albania, but the field still lacks the multi site baseline that exists for oil and gas reservoirs.
Extraction introduces complications the paper does not resolve. A purpose drilled well would need tighter casing to prevent contamination and a collection header connecting dozens of outlets into a volume worth compressing. None of that infrastructure exists at the Timmins mine today, and the authors describe their work as a first measured assessment of economic viability, several steps short of a producing well.
What a mine exhaling clean fuel actually changes
The significance is quieter than a breakthrough and louder than a footnote. Green hydrogen made from water and renewable electricity still costs several times more per kilogram than natural gas, which is why industrial users have been slow to commit. Natural hydrogen from rock would carry none of those production costs, because the energy input is geological time rather than a power purchase agreement.
The question is whether it can be gathered at scale without spending more energy on collection than the gas itself contains. The lead researcher said that if smart minds can figure out how to hook it up and use it, there is a win for the nascent hydrogen economy. To understand what happens when even carefully engineered hydrogen systems fail, it is worth reading about the Rossington electrolyzer and what it revealed about design assumptions. And for the frontier where clean fuels meet the hardest logistics problems, the tidal kites off Alaska show how remote communities are forcing engineers to think differently about energy delivery.
The mine near Timmins was never looking for hydrogen, and the hydrogen never stopped coming. For an industry that has spent billions trying to make the gas cleanly from scratch, that detail is worth sitting with. The rock has been patient, and the industry is only now catching up.
Hugo is an engineer with strong technical expertise. Multilingual from an early age, his writing combines technical clarity with a strong interest in science and energy.
