Is White Hydrogen Really a Low-Carbon Solution for the Energy Transition?
Introduction
The mining and energy sector plays a central role in the transition toward low-carbon energy systems. Beyond the extraction of critical minerals needed for clean technologies, new energy resources from the subsurface are now attracting the attention of industrial players and investors.
Among them, white hydrogen, also known as natural geological hydrogen, stands out for its natural origin and the low emissions associated with its extraction. Derived from continuous geological processes, it requires neither heavy industrial transformation nor major energy-intensive processes. This characteristic translates into a particularly low overall carbon footprint, today estimated among the lowest of all hydrogen production pathways according to the first available analyses.
Hydrogen in the Energy Transition: An Energy Carrier with Many Faces
Hydrogen is considered an essential energy carrier for decarbonizing sectors that are difficult to electrify, including heavy transport, heavy industry and industrial heat production. Recent studies show that lifecycle greenhouse gas emissions from trucks powered by hydrogen fuel cells are lower than those of conventional diesel trucks [8]. This ability to replace fossil fuels in demanding applications makes hydrogen a key element of the global energy transition.
However, the environmental impact of hydrogen depends entirely on its production method. Contrary to a common misconception, hydrogen is not automatically a clean solution: its carbon footprint varies considerably depending on the process used to produce it.
The Different Colors of Hydrogen and Their Carbon Footprints
The industry uses a color code to distinguish different types of hydrogen according to their production method and environmental impact.
Grey hydrogen, currently the most common, is produced by steam methane reforming without CO₂ capture. This process has a carbon footprint of approximately 10.13 kg CO₂eq/kg [1], making it the most polluting method. Natural Resources Canada specifies that grey hydrogen is the type of hydrogen for which CO₂ is not captured and stored underground [11].
Blue hydrogen uses the same steam reforming process as grey hydrogen, but incorporates carbon capture and storage technology at 90%. Its carbon footprint is therefore reduced to as low as 2.45 kg CO₂eq/kg [1], but remains significant due to residual emissions and the energy required for the capture process.
Green hydrogen is produced by water electrolysis using renewable electricity. Its footprint ranges from 1.0 to 4.5 kg CO₂eq/kg depending on production conditions [3], particularly the electricity source used and the efficiency of the electrolysis process.
The Emergence of White Hydrogen in the Energy Landscape
White hydrogen, also called natural or geological hydrogen, is fundamentally distinguished by its origin: it is extracted directly from the Earth's subsurface, where it is naturally produced by geological processes. This fundamental characteristic gives it unique environmental and economic properties.
The carbon footprint of white hydrogen is estimated at approximately 0.4 kg CO₂eq/kg for a gas containing 85% hydrogen, 12% nitrogen and 1.5% methane [1]. This value includes the embedded emissions related to extraction and processing, as well as fugitive emissions of hydrogen and methane.
Figure 1: Reference carbon emissions for hydrogen by production method (Source: MJ Hudson white hydrogen carbon footprint model, Beam Earth data)
White Hydrogen, a Natural Energy Source
Unlike other forms of hydrogen that require energy-intensive industrial processes, white hydrogen comes from natural geochemical reactions in the Earth's subsurface, which gives it unique environmental characteristics.
The Natural Formation Mechanisms of White Hydrogen
This resource is primarily produced by natural reactions such as serpentinization, where water reacts with iron-rich minerals at high temperatures [2]. This geological process transforms ultramafic rocks in the presence of water, generating hydrogen as a byproduct of this chemical reaction.
Radiolysis of water constitutes another source of natural hydrogen. This process involves radioactive elements present in the Earth's crust that split water molecules due to ionizing radiation [2]. These geological mechanisms occur continuously in certain areas of the globe, creating natural reservoirs of renewable hydrogen that replenish over time.
An Energy Source, Not Merely an Energy Carrier
The distinction between energy source and energy carrier is fundamental to understanding the advantage of white hydrogen. Unlike grey, blue or green hydrogen, which require a significant external energy input for their production, natural geological hydrogen is extracted from a system where chemical energy is already present in the subsurface. Lifecycle analyses indicate that its net energy ratio (Energy Return on Energy Invested – EROI) is approximately 10.8, meaning that the energy contained in the extracted hydrogen is far greater than the energy required for its extraction and processing [3]. This positive ratio distinguishes white hydrogen from other pathways, for which hydrogen acts primarily as an energy carrier, and allows it to be considered a true energy source.
Figure 2: Energy yield of white hydrogen Source: MJ Hudson white hydrogen carbon footprint model, Beam Earth data
Environmental Advantages
With emissions estimated between 0.24 and 0.35 kg CO₂e/kg H₂, white hydrogen presents a carbon intensity significantly lower than that of other hydrogen production pathways analyzed to date, notably green hydrogen and blue hydrogen, according to the scenarios evaluated [3][6]. These values come from a case study based on extraction conditions in Brazil, integrating all lifecycle stages from extraction to gas processing. While dependent on geological and operational contexts, these estimates indicate that natural geological hydrogen could display particularly favorable carbon performance in regions presenting similar conditions [3][6].
This carbon performance is explained primarily by the very nature of the extraction process, which relies on recovering a gas already present in the subsurface, without requiring heavy energy transformation or complex industrial processes.
In this context, renewable white hydrogen offers an opportunity for production with very limited CO₂ emissions, while not requiring intensive use of energy or heavy industrial infrastructure comparable to steam reforming or electrolysis installations [5]. This operational simplicity contributes to reducing both capital requirements, infrastructure costs and the overall environmental footprint of the production system.
Exceptionally Low Energy Intensity
The energy intensity of white hydrogen is ~3.09 kWh/kg H₂, compared to 42–64 kWh/kg for other production methods [6]. This difference is explained by the fact that white hydrogen requires no major energy transformation: it is extracted directly from the subsurface rather than being synthesized from other compounds.
The energy intensity of white hydrogen is 10 to 17 times lower than that of other hydrogen production pathways [6]. This remarkable energy efficiency translates directly into a reduced carbon footprint and theoretically competitive production costs.
| Hydrogen type | Energy intensity (kWh/kg H₂) | Net energy ratio |
|---|---|---|
| White hydrogen | 3.1 – 4.3 | 10.8 (source) |
| Green hydrogen | 48.3 – 64.0 | 0.52 – 0.70 (carrier) |
| Blue hydrogen | 43.3 – 47.7 | 0.69 – 0.73 (carrier) |
| Grey hydrogen | 42.7 – 53.3 | 0.63 – 0.78 (carrier) |
Table 1 : Comparative table of energy intensity for different types of hydrogen
Lifecycle Analysis: A Minimal Carbon Footprint from Extraction to Use
To rigorously assess the environmental impact of white hydrogen, it is necessary to analyze each phase of its lifecycle, from geological exploration through to its final use in energy applications.
Lifecycle Analysis Methodology
Lifecycle analysis (LCA) is a standardized methodology that evaluates all the environmental impacts of a product or service, from raw material extraction through to end of life. This approach avoids transferring impacts from one phase to another and ensures a complete and fair assessment.
A lifecycle analysis of white hydrogen, carried out from a Brazilian reference scenario, made it possible to estimate the carbon footprint of the different project phases [6]. These results are part of the first available work on the subject and contribute to documenting the environmental positioning of natural geological hydrogen relative to other existing pathways.
Distribution of Emissions by Lifecycle Phase
The lifecycle analyses currently available suggest that the carbon footprint of white hydrogen is distributed unevenly across the different project phases, with certain steps concentrating a larger share of emissions than others.
Exploration and evaluation
The initial phases, which include geological prospecting, resource evaluation and initial drilling, generate few emissions. Their contribution to the overall carbon balance remains marginal, due to the limited duration of these activities and their relatively low energy requirements.
Infrastructure development
The development phase, which includes setting up production infrastructure and drilling equipment, also generates a limited contribution to the overall carbon footprint. The upstream project stages remain secondary compared to the emissions associated with later phases.
Gas production and processing
The production phase represents the main source of emissions, concentrating approximately 97% of the total carbon footprint in the analyzed scenarios [6]. This concentration is explained primarily by gas processing operations and the technological choices associated with hydrogen separation and purification.
Operational components of production
Within the production phase, gas filtration and purification constitute the primary source of emissions. Fugitive emissions, related to hydrogen or methane losses, remain marginal. Routine operations, such as maintenance and monitoring of installations, contribute negligibly to the overall footprint.
Site closure and end of life
Emissions associated with site closure are considered very low, even negligible, due to the relative simplicity of end-of-life operations compared to heavy industrial installations.
Taken together, these elements show that the overall carbon footprint of white hydrogen remains low across its lifecycle, with a favorable emission structure concentrated on clearly identified technical stages, offering optimization margins as the sector develops.
Note:The phases and orders of magnitude presented above are based on lifecycle analyses drawn from scientific literature and reference scenarios. They may vary according to the geological characteristics, technological choices and operational conditions specific to each production site. They do not necessarily prejudge the lifecycle or practices that will be implemented in the specific projects developed by Squatex.
Carbon-Neutral Drilling Technologies in Quebec
Innovation developed in Quebec is also contributing to exploring ways to reduce the environmental footprint associated with drilling activities, including in the context of white hydrogen. Caron Technologies International (CTI) is part of this dynamic through the development of electrified drilling platforms aimed at limiting direct emissions, energy consumption and surface footprint. Compact equipment, such as crawler-mounted drilling rigs designed for precision drilling capable of reaching depths on the order of 1,000 meters, illustrates an approach oriented toward reducing operational impacts. This type of technological innovation reflects ongoing efforts to adapt drilling practices to the growing environmental requirements of the mining and energy sector.
Conclusion
The lifecycle work currently available suggests that white hydrogen could occupy a singular place among emerging low-carbon options, due to its natural origin and the relative simplicity of its production method. Without requiring heavy energy transformation, it invites a rethinking of hydrogen's role not solely as a carrier, but as a potential energy resource drawn from the subsurface, subject to favorable geological and operational conditions.
In this context, the development of natural geological hydrogen rests on a progressive approach, grounded in exploration, scientific validation and the adaptation of industrial practices to local realities. It is within this dynamic that the work and reflections carried out by Squatex are situated, aiming to better understand the potential of this resource and its possible role in the energy systems of tomorrow. To learn more about advances related to white hydrogen and discover how Squatex is contributing to the evolution of this sector, follow us on LinkedIn to stay informed of recent developments in the low-carbon energy sector.
References
[1] IEA GHG. "Gold, Geologic, White, Native, Hidden, Natural: Hydrogen - Does Earth Hold Extensive Stores of Untapped Carbon-Free Fuel?" IEA Greenhouse Gas R&D Programme, 2024, https://ieaghg.org/insights/gold-geologic-white-native-hidden-natural-hydrogen-does-earth-hold-extensive-stores-of-untapped-carbon-free-fuel/.
[2] Rystad Energy. "White Gold Rush: The Pursuit of Natural Hydrogen." Rystad Energy News, 2024, https://www.rystadenergy.com/news/white-gold-rush-pursuit-natural-hydrogen.
[3] MJ Hudson. "White Hydrogen Carbon Footprint Study." Beam Earth, 2022, https://www.beam.earth/wp-content/uploads/2022/02/MJ-Hudson-White-hydrogen-carbon-footprint-220128.pdf.
[5] Beam Earth. "White Hydrogen Overview." Beam Earth, https://www.beam.earth/white-hydrogen/.
[6] MJ Hudson. "White Hydrogen Carbon Footprint - Detailed Lifecycle Assessment." Beam Earth, 2022, https://www.beam.earth/wp-content/uploads/2022/02/MJ-Hudson-White-hydrogen-carbon-footprint-220128.pdf.
[8] U.S. Department of Energy. "GREET Hydrogen Fact Sheet." Office of Energy Efficiency & Renewable Energy, janvier 2025, https://www.energy.gov/sites/default/files/2025-01/rd-greet-hydrogen-fact-sheet_january-2025.pdf.
[11] Ressources Naturelles Canada. "Natural Hydrogen: A Solution for the Energy Transition?" Simply Science, 2024, https://natural-resources.canada.ca/stories/simply-science/natural-hydrogen-solution.
