Underground Hydrogen Production Gains Attention as Low Carbon Alternative

Hydrogen is widely considered essential for decarbonizing sectors that are difficult to electrify, including steel, cement, chemicals, refining, and parts of heavy transport. Governments in Europe, North America, and Asia have published hydrogen strategies that focus largely on green hydrogen from renewable-powered electrolysis and blue hydrogen from natural gas with carbon capture.

However, both pathways face cost, infrastructure, and scalability constraints. Electrolysis requires significant renewable electricity capacity and large capital investment. Blue hydrogen depends on high carbon capture rates and strict methane leak control to maintain climate credibility.

Against this backdrop, interest is growing in an alternative concept: producing hydrogen directly underground.

How Underground Hydrogen Production Works

Geological or in situ hydrogen production builds on a natural process known as serpentinisation. In certain iron-rich rock formations, water reacts chemically with minerals to generate hydrogen over time.

Researchers are exploring whether injecting water into suitable deep rock formations can accelerate this reaction and enable continuous hydrogen production. Wells would then be used to extract the gas, using techniques similar to those developed in the oil and gas sector.

In some models, the geological formation could serve both as a production site and as a storage reservoir. This dual function could reduce the need for additional surface storage infrastructure, which remains one of the major challenges in hydrogen deployment.

Pilot-scale projects and feasibility studies are being evaluated in regions with favourable geology, including parts of North America, Europe, and Australia. The concept remains in early development, with technical validation still required.

Potential Advantages and Industrial Relevance

Proponents argue that underground hydrogen could offer several advantages. Surface land use may be lower compared with large electrolysis facilities. Existing drilling expertise and infrastructure could be repurposed, supporting workforce transition in traditional energy regions.

If production rates are sufficient, underground hydrogen could provide a steady supply for industrial users, particularly in areas close to suitable geology. This proximity could reduce transport costs, another barrier in the hydrogen value chain.

From a strategic perspective, adding another production pathway could enhance energy security and diversify supply sources as global hydrogen demand grows.

Environmental and Regulatory Considerations

Despite its potential, underground hydrogen production faces important challenges. Reaction rates must be high enough to sustain commercial-scale output. Water injection volumes, pressure management, and gas extraction require careful engineering to prevent unintended impacts.

Environmental safeguards will be critical. Monitoring systems must address risks such as groundwater contamination and induced seismicity. Lifecycle emissions, including energy used for drilling and pumping, will need a transparent assessment to determine whether underground hydrogen meets clean hydrogen thresholds.

Regulatory frameworks may also require updates. In many jurisdictions, hydrogen does not yet have a clearly defined legal status in subsurface resource laws, which were designed primarily for hydrocarbons and minerals.

Outlook for Deployment

Underground hydrogen is unlikely to displace green or blue hydrogen in the short term. Instead, it may emerge as a complementary option within a diversified supply portfolio.

Demonstration projects, independent data verification, and clear carbon accounting standards will shape investor confidence and policy support. If technical hurdles can be overcome, underground hydrogen could add a novel supply stream to the clean energy transition, leveraging geological processes to help meet rising demand for low-carbon fuels.

Source: www.forbes.com