Trillions of tons of hydrogen may be waiting under our feet

A new energy industry is emerging around hydrogen made by rocks instead of renewables

PICREL: Hydrogen from geological formations makes up about 10% of the flammable gases that form the Yanartaş flames near Cirali, Türkiye. The fires are said to have been burning for thousands of years and may be the flaming rocks mentioned in the myth of the Chimera.

Hydrogen is a popular molecule right now. Billions of dollars are flowing from investors and governments into projects to make more hydrogen and use it to decarbonize both industry and transportation. But what’s often lost in the discussion is that hydrogen is really an energy transfer medium, not an energy source.

The hydrogen available today is made in processes that are powered by renewable energy or, more often, fossil fuels. Molecular hydrogen as it is used and traded now is no more or less sustainable than the energy used to create it.

Except, that is, in Bourakebougou, a small town in southwestern Mali. There, almost 40 years ago, engineers drilling for water tapped instead into a natural underground reservoir of hydrogen gas. What they saw---a dry well emitting wind instead of water—was at first a disappointment.

Then, according to local lore, it became a catastrophe. A worker smoking a cigarette accidentally ignited the gas stream, creating a huge plume of smokeless fire that burned for weeks before workers were able to extinguish it. Tests showed it wasn’t natural gas, so they capped the borehole and walked away.

The idea of tapping such geological hydrogen had been confined to academic circles until around 2012, when Aliou Diallo, a Malian businessman, hired a mobile analytical laboratory to characterize the gas at the site. Diallo had purchased oil and gas exploration rights in the area after hearing about the flaming well.

The mobile lab found 98% pure hydrogen. For Bourakebougou, the discovery brought the fuel needed to generate reliable electricity, at first via a modified car engine and later through purpose-built equipment. It also changed Diallo’s business, which is now called Hydroma and is focused on geological hydrogen.

Diallo is part of a growing crowd of geochemists, entrepreneurs, and investors who see opportunities worldwide to develop geological hydrogen as a primary energy source with little impact on the climate, unlike carbon-containing fossil fuels. Companies are drilling about 200 exploration wells across the globe, mostly in secret, according to industry sources. But so far, Bourakebougou is the only one to produce anything of any economic value, and experts don’t know if geological hydrogen will remain a useful curiosity or launch a new energy economy.

Clean energy under our feet

Douglas Wicks, a program director exploring geological hydrogen for the US Department of Energy’s Advanced Research Projects Agency--Energy (ARPA‑E), says one reason there aren’t more productive projects is that no one has been looking for the gas underground until recently. “The Earth has been producing hydrogen at large volumes for all of history,” he said during a panel discussion on geological hydrogen at Climate Week NYC in September. “We just chose as humankind not to really pay attention.”

https://cen.acs.org/energy/hydrogen-power/Trillions-tons-hydrogen-waiting-under/103/i7?ref=search_results