Natural hydrogen reserves: Mountains as untapped energy wells
Recent studies suggest that the mountains may harbour vast reserves of naturally occurring hydrogen gas – potentially providing us access to a substantial, untapped source of clean energy. The study results were published in "Science Advances".
These gas reservoirs hidden in mountain ranges may have been formed over millions of years, according to researchers. An international team, including geophysicist Sascha Brune from the GFZ Helmholtz Centre for Geosciences, conducted simulations of tectonic plate movements and mountain formations to understand hydrogen production processes. Although hydrogen can be produced artificially, the process is challenging and often results in greenhouse gas emissions, which somewhat defeats the purpose. Discovering large natural reserves would be a remarkable step forward for clean energy technology. The latest findings on this topic were published in the scientific journal "Science Advances".
Hydrogen inside the mountains
"This new research advances our understanding of suitable environments for natural hydrogen generation," said geophysicist Sascha Brune from the GFZ Helmholtz Centre for Geosciences in Germany, in an interview with Science Alert. "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.," he added.
The researchers focused on a process known as serpentinisation, where the mantle beneath the crust is pushed upwards and comes into contact with water. This results in a chemical reaction where hydrogen gas is produced. This process can occur when continents break apart and when they drift towards each other, as the Earth's mantle can rise upward in both scenarios. Through their simulations, scientists identified where and when serpentinisation is most likely to occur. This process is much more likely in mountains, where the plates converge, rather than where they diverge – researchers found it to be possible even about 20 times more due to water cycles and temperature ranges.
The Pyrenees, Alps, Balkans may hide hydrogen reservoirs
Moreover, accessing hydrogen reservoirs inside mountains may be relatively easier compared to other locations such as mid-ocean ridges. Plans for hydrogen exploration already include the Pyrenees, the Alps, and the Balkans. Frank Zwaan from the GFZ Helmholtz Centre for Geosciences emphasises that novel concepts and exploration strategies, considering the tectonic history of an area, will be crucial for success.
While this study does not provide a global estimate of the amount of hydrogen that may be hidden, previous analyses concerning serpentinisation in the eastern Pyrenees suggest, according to researchers, that the hydrogen stored there could be sufficient to meet the needs of half a million people annually. This presents an exciting prospect for an energy source that produces water, not carbon dioxide as its main waste product.
The birth of a new hydrogen industry
Frank Zwaan notes that we might be witnessing the inception of a new natural hydrogen industry. "Overall, we may be at a turning point for natural H2 exploration," comments Zwaan. "As such, we could be witnessing the birth of a new natural hydrogen industry." The scientific team stated that much work remains to confirm the presence of this hydrogen gas, utilise it, and ensure a sustainable process, but we can be more optimistic than ever.
