Researchers say an untapped source of clean energy has been hiding beneath Western Australian soil, where some of the world’s largest iron deposits could harbor an unexpected secret.
These deposits, according to researchers at Edith Cowan University (ECU), are also rich in magnetite capable of producing hydrogen when it interacts with hot water, under conditions that mirror those which occur naturally deep underground.
Such processes, the researchers say, could be stimulated in magnetite-rich locations like Western Australia’s naturally reddish Pilbara region, stimulating hydrogen production and potentially unleashing a valuable, untapped clean energy source.
An Unexpected Source of Energy
Magnetite is abundant within the Pilbara’s vast banded iron formations, and when subsurface temperatures rise, the naturally occurring interactions between this iron-rich mineral and water lead to chemical reactions—the same kind which can produce molecular hydrogen.
“Australia could be sitting on a massive, untapped energy reserve,” said ECU Associate Professor Alireza Keshavarz of the team’s recent discovery, “and the potential is enormous.”
To better understand the processes that may hold the key to unlocking Australia’s untapped subsurface energy reserves, the ECU team began by placing samples of magnetite in water heated to 200 degrees Celsius and under extreme pressure. The experiments continued for close to two months, during which time the researchers were able to recreate some of the same conditions that occur naturally deep within the Earth.
Doing so allowed the team to look at how hydrogen naturally forms, as well as what geological conditions help to sustain its production.
“Western Australia has some of the world’s largest banded iron formations,” said Kaveh Moghanirahimi, the lead author of a recent study detailing the team’s findings.
“If we can unlock this resource at scale, it could be transformative for our energy future,” he adds.
Water May Hold the Key
Significantly, the team says they found that just having large amounts of magnetite in subsurface deposits may not be all that is required for significant hydrogen production. Another key component is having enough water present to be able to reach fresh mineral surfaces for the hydrogen-producing reactions to continue.
Importantly, the researchers found that simply having large quantities of magnetite underground may not be enough. Water must also be able to reach fresh mineral surfaces for the hydrogen-producing reactions to continue.
“Our findings show that hydrogen production depends not only on the amount of magnetite present, but also on how easily water can access fresh mineral surfaces through fractures, pores, and permeable pathways,” said Professor Stefan Iglauer, a researcher with ECU’s School of Engineering.
Hydrogen through Injection?
The researchers also say they have identified a potential method for stimulating hydrogen generation by injecting a solution into banded iron formations. This, they say, points to a novel possibility: that geological deposits of the right specific kind may also one day function as sites for engineered production of naturally generated hydrogen.
That possibility, the researchers argue, could prove to be significant as governments and industries seek lower-emission alternatives to hydrogen currently produced mainly using fossil fuels. Also, unlike conventional methods of hydrogen manufacturing, tapping geological hydrogen only requires leveraging natural reactions that occur underground.
A Step Toward the Future of Clean Energy
Presently, the research remains an early step toward determining whether the process can be translated from lab experiments into a commercially viable method of producing clean energy with the resources present in natural geological formations.
However, if researchers can continue to capitalize on methods that allow hydrogen to be generated and recovered at economical scales, there are already remarkable possibilities in terms of what Western Australia’s enormous iron formations could one day help provide.
“This work helps bridge the gap between laboratory experiments and real geological systems,” Iglauer said.
The team recently reported its findings in the paper, “Geometry-driven controls on hydrothermal natural hydrogen generation from magnetite mineral,” published in the International Journal of Hydrogen Energy.
Micah Hanks is the Editor-in-Chief and Co-Founder of The Debrief. A longtime reporter on science, defense, and technology with a focus on space and astronomy, he can be reached at micah@thedebrief.org. Follow him on X @MicahHanks, and at micahhanks.com.