Beyond the Hydrogen Rainbow: Why the Subsurface Matters More Than Ever
At the World Hydrogen & Carbon Americas Conference, where I was honored to speak on the panel “The Race for Geological Hydrogen: What Do We Know So Far,” one idea consistently surfaced across conversations on technology, policy, and investment. The future of hydrogen depends just as much on where it is produced as how it is produced.
For years, the hydrogen economy has been framed around a familiar concept known as the hydrogen rainbow. Green, blue, and turquoise hydrogen describe production methods and carbon outcomes. These categories are quickly becoming obsolete as they are only part of the picture.
The industry is beginning to shift its focus. The subsurface is emerging as one of the most important drivers of scalable hydrogen production, and much of the work we do at Eclipse Energy is centered on advancing how that potential can be realized.
Looking Below the Surface
Subsurface hydrogen is not a new idea, but it is rapidly gaining attention. Naturally occurring hydrogen has been identified in the Earth’s crust for decades. What has changed is the level of interest in developing it as a resource.
Estimates referenced during the panel suggest that even a small portion of recoverable natural hydrogen could significantly contribute to global energy supply. This has sparked new efforts in geological mapping, exploration, and research into how hydrogen forms underground.
Simultaneously, advancements in subsurface technologies are expanding what is possible. Hydrogen can now be generated, stored, and produced within geological formations. This enables solutions that go beyond traditional surface production methods like electrolysis.
For an industry that depends on scale, this is critical. The subsurface offers the kind of volume and repeatability that large energy systems require.
Unlocking Value from Existing Infrastructure; Turning Energy Liabilities Into Assets
Of course, I believe one of the most compelling subsurface opportunities lies in places the energy industry already knows well: mature oil reservoirs.
Globally, millions of wells have already been drilled, and many reservoirs still contain substantial hydrocarbons that are no longer economical to produce through conventional methods. In fact, estimates suggest that as much as two-thirds of the original petroleum in many reservoirs remain underground.
Traditionally, these wells are viewed as liabilities once production declines. They then must eventually be plugged and abandoned at significant cost. The panel discussion allowed me to highlight a different perspective: these reservoirs may represent the next generation of hydrogen infrastructure.
By stimulating microbial processes underground, remaining hydrocarbons can be converted into hydrogen. This approach, being pioneered by Eclipse Energy, offers a powerful reframing of energy security options. Instead of abandoning legacy infrastructure, the industry can repurpose it to produce clean energy, leveraging decades of subsurface expertise and existing wells.
For regions with mature oil and gas basins, the implications are significant. What were once declining hydrocarbon liabilities could become hubs of hydrogen production.
The Role of Economics
A point of ongoing discussion in our industry is no matter how promising the technology is, hydrogen must compete on cost. To reach widespread adoption, hydrogen needs to be economically competitive with fuels like natural gas and diesel across sectors such as transportation, industry, and power generation. This is one of the biggest challenges facing the hydrogen economy today.
Technology pathways that provide a levelized cost of hydrogen that is competitive with incumbents are gaining industry attention. Eclipse’s approach, for example, makes use of existing wells, reduces the need for new infrastructure, and relies on natural geological and microbial processes.
For us, economic viability is always central to how we evaluate opportunity. Scalable hydrogen solutions must be both technically sound and commercially practical.
A Lasting Shift in the Hydrogen Economy
The big takeaway from the conference, and our panel, is that while subsurface hydrogen techniques are developing, the pace of progress has accelerated rapidly. What was once a niche area of research is now showing cost pathways on par with fossil fuels, attracting investment, shaping strategy, and appearing in major industry discussions.
We believe the future of hydrogen will be shaped by solutions that can scale efficiently and operate within real-world constraints. The solutions may be closer than we think, waiting just below the surface.
Abbie Booker serves as our Senior Business Development Associate here at Eclipse Energy and has been with us since the start. She has a background in biology that led her into the startup space, where she's worked on everything from lab operations to procurement. She uses her experience across every facet of our business to deliver partnerships, market analysis, and provide our clients with a full-life-cycle commercialization strategy.