In a groundbreaking discovery, scientists have identified an untapped and potentially transformative energy resource hidden deep beneath the Earth’s surface: trillions of tons of geologic hydrogen gas. This naturally occurring hydrogen could provide clean energy for the world for centuries, according to recent research led by Geoffrey Ellis of the U.S. Geological Survey. The study, published in Science Advances, suggests that harnessing this resource could significantly reduce global reliance on fossil fuels and help combat climate change.

The Hidden Potential of Geologic Hydrogen

Hydrogen has long been touted as a clean and efficient energy carrier, capable of powering everything from cars to industrial processes with water as its only byproduct. While most hydrogen used today is produced from natural gas or through electrolysis of water, these processes are either carbon-intensive or costly. The discovery of geologic hydrogen, however, offers a more sustainable and potentially abundant alternative.

Geologic hydrogen is formed naturally through geochemical processes that occur deep within the Earth’s crust. Unlike hydrogen extracted from water, this form of hydrogen is a byproduct of reactions between water and certain minerals in the Earth’s mantle. These reactions, known as serpentinization and radiolysis, create vast reservoirs of hydrogen gas trapped in porous rock formations.

Researchers didn't think hydrogen accumulates underground, but recent discoveries suggest otherwise. (Image credit: Terryfic3D via Getty Images)

Ellis and his team estimate that these reserves total around 6.2 trillion tons (5.6 trillion metric tons) globally, an amount far exceeding all proven natural gas reserves combined. If just a fraction of this hydrogen could be tapped, it could meet the world’s energy needs for centuries, all while contributing to a reduction in greenhouse gas emissions.

A Clean Energy Source for 1,000 Years

One of the most striking findings of the study is the sheer scale of Earth’s hydrogen reserves. According to the researchers, extracting just 2% of the estimated total could provide enough energy to meet global hydrogen demand for the next 200 years. If deeper and more inaccessible reserves could be reached, this resource could potentially last over 1,000 years, offering a long-term solution to the world’s growing energy crisis.

The environmental benefits of such a resource are immense. Hydrogen, when used as a fuel, emits only water vapor, making it a zero-emission energy source. By replacing fossil fuels like coal, oil, and natural gas with geologic hydrogen, the world could make significant strides toward achieving net-zero carbon goals. This would be particularly beneficial for hard-to-decarbonize sectors such as heavy industry, shipping, and aviation.

Global Hydrogen Deposits: A Geographical Overview

Although much of Earth’s geologic hydrogen remains hidden, researchers have already identified significant reserves in specific regions. For instance, natural hydrogen seeps have been discovered in Albania, Mali, and Brazil, among other locations. These deposits, while relatively small compared to the overall global estimate, provide a glimpse into the vast potential of this energy source.

Geologists believe that similar deposits may exist in many other parts of the world, including regions rich in ultramafic rocks, which are known to host hydrogen-producing reactions. However, much of this hydrogen is likely buried deep beneath the Earth’s surface or located offshore, presenting significant challenges for exploration and extraction.

To fully realize the potential of geologic hydrogen, scientists and energy companies will need to develop advanced drilling and extraction technologies. These innovations could make it possible to access deep hydrogen reservoirs while minimizing environmental impacts and ensuring the economic viability of hydrogen production.

Overcoming the Challenges of Extraction

Despite its promise, tapping into geologic hydrogen is not without its challenges. For one, the technology needed to extract hydrogen from deep reservoirs is still in its infancy. Unlike oil and natural gas, which have been extensively studied and exploited for over a century, geologic hydrogen remains a relatively new frontier in energy exploration.

Professor Bill McGuire of University College London has highlighted the scale of the effort required to develop the necessary infrastructure. “Extracting hydrogen at scale would demand a massive global initiative,” McGuire said. This includes developing specialized drilling equipment, refining hydrogen separation processes, and building pipelines and storage facilities for large-scale distribution.

Another significant hurdle is the economic feasibility of hydrogen extraction. While the cost of producing hydrogen from geologic sources is expected to decrease as technology advances, it must compete with other energy sources, including renewables like solar and wind. Governments and private investors will need to provide substantial funding and incentives to drive innovation and build the infrastructure needed to bring geologic hydrogen to market.

The Role of Hydrogen in Achieving Climate Goals

The potential of geologic hydrogen goes beyond its ability to replace fossil fuels. It could play a critical role in the global transition to sustainable energy by complementing other renewable energy sources. For example, hydrogen can be used to store excess energy generated by solar and wind farms, helping to address the issue of intermittency and ensure a stable energy supply.

View of a construction site with storage tanks for "green hydrogen," the product of electrolysis of water using renewable energy. (Image credit: Yaorusheng via Getty Images)

Moreover, hydrogen has applications in industries that are difficult to decarbonize using electricity alone. In steelmaking, for instance, hydrogen can be used as a reducing agent to replace coal, significantly reducing carbon emissions. Similarly, hydrogen-powered fuel cells are already being used in some buses, trucks, and trains, offering a clean alternative to diesel engines.

By integrating geologic hydrogen into the energy mix, countries could accelerate their progress toward meeting the targets set by the Paris Agreement and limit global warming to well below 2 degrees Celsius.

The Future of Geologic Hydrogen Research

Given its potential to transform the global energy landscape, geologic hydrogen has become a hot topic in scientific and industrial circles. The study by Ellis and his team has already sparked interest among energy companies and policymakers, who see hydrogen as a key pillar of the future energy economy.

However, much remains to be learned about the distribution, accessibility, and behavior of hydrogen reservoirs. Future research will need to focus on identifying the most promising locations for exploration, understanding the geochemical processes that produce hydrogen, and developing more efficient extraction methods.

Collaboration between governments, research institutions, and the private sector will be essential to unlock the full potential of geologic hydrogen. By investing in research and innovation, the world could take a significant step toward a cleaner, more sustainable energy future.

Conclusion: A Game-Changer in Clean Energy

The discovery of trillions of tons of geologic hydrogen buried deep within the Earth’s crust represents a potential game-changer in the quest for sustainable energy. With the ability to power the world for centuries and reduce greenhouse gas emissions, this untapped resource could play a pivotal role in the fight against climate change.

While significant challenges remain, including the need for advanced extraction technologies and substantial investment, the promise of geologic hydrogen is too great to ignore. This clean energy source has the potential to complement other renewable energy solutions like wind and solar, creating a more resilient and diversified energy grid. Moreover, its extraction could spur technological advancements, opening doors to economic growth and new industries focused on hydrogen production and distribution.

As researchers continue to explore this exciting frontier, the world stands on the brink of a new era in clean energy, one that could shape the future of our planet for generations to come. The journey to unlock geologic hydrogen’s full potential will require global collaboration, innovation, and a shared commitment to sustainability.