The Underground Hydrogen Rush: Companies Race to Tap Naturally Occurring Hydrogen Gas

A new field of energy exploration is drawing comparisons to a 21st-century gold rush: the hunt for naturally occurring hydrogen gas trapped underground, according to reporting by MIT Technology Review. Today, almost all hydrogen is made from fossil fuels, mostly natural gas, and used largely in petroleum refining and to make fertilizer and other chemicals. Two methods long proposed for cleaner hydrogen -- electrolysis powered by renewable electricity, and fossil-fuel-based production paired with carbon capture -- have struggled to gain ground because of high costs.

In recent years, momentum has shifted toward geologic hydrogen: gas that forms naturally underground and has been found by companies across Africa, Asia, Europe, Australia and North America. The U.S. Geological Survey publishes a map of where such hydrogen is most likely to occur; one hot spot is the Midcontinent Rift, running from Kansas to Michigan, where the Earth's crust stretched and split about a billion years ago, pushing up iron-rich rock that reacts with water to readily form hydrogen. HyTerra, an Australian company searching for hydrogen across Nebraska and Kansas, has already found gas samples with hydrogen concentrations up to 96%, while Koloma, one of the most heavily funded companies in the field with more than $400 million raised, is prospecting in the same region.

A central question is how much hydrogen these formations actually produce and whether it can be captured, since hydrogen's light molecules can slip through even tiny cracks in rock. In one signal of the potential scale, researchers examining boreholes at a mine in northern Ontario found that each one released eight kilograms of hydrogen a year -- and the site has more than 14,000 boreholes.

Other companies are trying to trigger hydrogen production directly: Vema Hydrogen, based in Texas, drills wells and injects water and catalysts into rock to kick-start hydrogen-forming reactions, and is testing the process in wells in Quebec with hopes of full-scale production by 2028, while Eden GeoPower uses electricity to fracture rock and create more pathways for water to reach reactive formations.