In a new story for our latest print issue, freelance reporter James Dineen took a look at the 21st-century gold rush for naturally occurring hydrogen gas. This is an area of research I’ve been fascinated by lately, so let’s take a look at the potential and the questions that still linger.   Today, hydrogen is overwhelmingly made using fossil fuels, generally natural gas. And most of it is used in petroleum refining or goes on to make fertilizer and other chemicals. But in recent years, many in the climate world have imagined a future where its production is clean too. If you’d asked me a few years ago, I would have said the race for clean hydrogen was between methods that use electrolyzers powered with renewable electricity and operations that use established, fossil-fuel-based approaches cleaned up with carbon capture. But both those methods have struggled to gain ground, largely because of their high cost. Lately, there’s been momentum in a new field: geologic hydrogen. Companies have found naturally occurring hydrogen resources across Africa, Asia, Europe, Australia, …

The results from Kidd Creek add to “the growing evidence that natural hydrogen generation and migration are genuine geological processes,” says Laurent Truche, a geochemist at the University of Grenoble Alpes in France. In 2024, his research team reported that at least 200 metric tons of the gas flow out of the Bulqizë chromium mine in Albania every year. “The remaining challenge is not proving that natural hydrogen exists, but proving that it can be produced economically and reliably at commercial scale,” Truche says. Proof, however, doesn’t necessarily require striking the mother lode. Researchers and startups are also exploring the possibility of stimulating hydrogen production by injecting water, heat, or catalysts into the reactive rocks that naturally produce the gas. More than a dozen of these projects are funded by ARPA-E, which has established a goal of accelerating the hydrogen-producing reaction by a factor of 10,000—the rate at which, researchers estimate, stimulated H2 production would be commercially viable. An indication that this could work came earlier this year from the mountains of Oman, where a …