New research suggests there could be massive reserves of naturally occurring hydrogen gas hiding away in the mountain ranges of the world – potentially giving us access to a huge, untapped source of clean energy.
These reservoirs of gas would have been produced over millions of years, the study suggests. An international team of researchers combined field recordings with computer modeling to simulate plate tectonic movement, mountain formation, and the possible production of hydrogen.
While there are ways to produce hydrogen artificially, it’s not easy – and they typically emit greenhouse gases along the way, which somewhat defeats the point. Finding large natural reserves would be an incredible step forward for the clean energy technology.
“This new research advances our understanding of suitable environments for natural hydrogen generation,” says geophysicist Sascha Brune, from the GFZ Helmholtz Centre for Geosciences in Germany.
“Given the economic opportunities associated with natural H2, now is the time to go further and also investigate migration pathways of hydrogen and deep, hydrogen-consuming microbial ecosystems to better understand where potential H2 reservoirs can actually form.”
The researchers focused specifically on a process called serpentinization, where mantle below the crust is pushed upwards and comes into contact with water. The resulting chemical reaction produces hydrogen gas.
This can happen as continents break apart and as they push together, as Earth’s mantle can rise upwards in both scenarios. Through their simulations, the researchers identified where and when serpentinization was most likely to be happening.
Serpentinization is probably much more common in mountain range settings where plates are pushed together, compared to where they’re pulled apart – about 20 times more likely, the researchers found, due to water cycles and temperature ranges.
What’s more, hydrogen reservoirs inside mountains might be relatively simple to access compared to other places we’ve been looking, including ocean ridges. Plans are already underway to search for hydrogen in the Pyrenees, the European Alps, and the Balkans.
“Crucial to the success of these efforts will be the development of novel concepts and exploration strategies,” says structural geologist Frank Zwaan, from the GFZ Helmholtz Centre for Geosciences.
“Of particular importance is how the formation of economic natural H2 accumulations is controlled by the tectonic history of a given exploration site.”
While this study doesn’t give a global estimate for the amount of hydrogen that might be hidden away, earlier research analyzing serpentinization in the eastern Pyrenees suggests the hydrogen stored there could be enough to meet the needs of half a million people annually.
That’s an exciting prospect for an energy source that produces water rather than carbon dioxide as the main waste product. There’s plenty of work to do to confirm the presence of this hydrogen gas, to tap into it, and ensure the process is sustainable, but we can be more hopeful than ever.
“Overall, we may be at a turning point for natural H2 exploration,” says Zwaan. “As such, we could be witnessing the birth of a new natural hydrogen industry.”
The research has been published in Science Advances.
