The Biden administration and several leading companies are exploring a new approach to hydrogen production: extracting it from underground sources. This method, referred to as “gold hydrogen,” has recently seen increased interest, partly due to a $20 million funding opportunity presented by the Department of Energy’s Advanced Research Projects Agency-Energy.
What is Gold Hydrogen?
Gold hydrogen is hydrogen gas that occurs naturally underground, typically within subsurface reservoirs. The extraction method resembles conventional oil and gas drilling. This hydrogen forms through various geological processes, such as chemical reactions between water and iron-rich rocks or radiolysis, where radiation splits water molecules into hydrogen and oxygen.
Geoffrey Ellis, a research geologist at the U.S. Geological Survey, estimates that there may be as much as 5 million megatons of gold hydrogen worldwide. If just 2% of this could be extracted, it might provide a hydrogen supply for 200 years, potentially playing a significant role in meeting net zero emissions goals. Additionally, gold hydrogen has a notable advantage over other hydrogen production methods as it does not require external energy inputs to be generated.
A Global Gold Rush for Buried Hydrogen
Geologists have identified hydrogen reserves in various locations worldwide, including France, Spain, Africa, Brazil, and the U.S. The International Energy Agency estimates that by 2050, hydrogen demand for a net zero scenario will reach 430 million tonnes. With an estimated five trillion tonnes of natural hydrogen reserves globally, tapping into a small fraction could meet energy needs for centuries.
Several startups and established companies are pursuing gold hydrogen projects. HyTerra, based in Australia, is preparing to drill for hydrogen at a site in Kansas and is also working with Natural Hydrogen Energy on Project Geneva in Nebraska. Koloma, a Denver-based firm supported by Bill Gates’ Breakthrough Energy, has secured $91 million and is exploring drilling locations in the U.S. However, specific drilling sites and commercialization plans have not been publicly detailed.
Currently, the only operational gold hydrogen well is located in Bourakébougou, Mali. The well has been producing nearly pure natural hydrogen since 2012, and new discoveries suggest there are more substantial deposits than previously known. These deposits are believed to form where iron-rich rocks in the Earth’s crust react with water. This well produces a modest amount of energy sufficient for local use but is not yet commercially viable.
Before gold hydrogen can be extracted on a large scale, it is crucial to gain a deeper understanding of it. To fill these knowledge gaps, Alberto Vitale Brovarone, a professor at the University of Bologna, along with his team and other researchers, traveled to Greenland. The expedition, conducted under the ERC CoG DeepSeep program funded by the European Union, sought to collect more data on gold hydrogen in one of the world’s oldest geological formations. The team spent ten days in Greenland, where they collected samples rich in hydrogen. The samples will help researchers investigate how gold hydrogen accumulates and its role in subsurface ecosystems.
Cost and Economic Viability of Gold Hydrogen
One of the key benefits of gold hydrogen is its potential for low production costs. Koloma estimates that gold hydrogen could be produced at a cost of under $1 per kilogram, making it a competitive alternative to hydrogen generated from fossil fuels or electricity. If these cost projections are accurate, gold hydrogen could become a viable option in the energy market.
The Department of Energy has set a goal to achieve a cost of $1 per kilogram for clean hydrogen by 2031, which aligns with the potential economic advantages of gold hydrogen.
The Future of Gold Hydrogen: What Lies Ahead
As researchers continue to explore the potential of gold hydrogen, the balance between rapid industrial interest and the need for thorough scientific investigation is paramount. The findings from missions like those led by Vitale Brovarone’s team will play a key role in shaping the future of gold hydrogen and its role in the global energy landscape. The U.S. government’s support, through funding opportunities and tax incentives, highlights the importance of this production pathway in advancing clean energy and achieving climate objectives. Alongside green and blue hydrogen, gold hydrogen could potentially become an accelerated pathway for a net zero transition.
