Request for Information (RFI): Stimulating Geochemical Reactions in the Subsurface for in-situ Generation of Hydrogen and Helium Production | DE FOA 0002786

Opportunity Information: Apply for DE FOA 0002786

This opportunity is a Department of Energy ARPA-E Request for Information (RFI) focused on a possible future research program about using the subsurface as a kind of engineered chemical reactor to generate hydrogen and helium with little to no carbon emissions. It is not a grant solicitation and it is not accepting funding applications. Instead, ARPA-E is collecting technical and programmatic input from researchers, companies, and other stakeholders to help decide whether and how to shape a future funding program aimed at subsurface chemical production and the related challenge of separating and producing useful gases at the surface.

The core idea ARPA-E wants to pressure-test is whether underground environments can be intentionally stimulated to drive geochemical reactions that produce hydrogen at a cost level aligned with DOE's Hydrogen Shot goal of $1 per kilogram, while also potentially producing helium without carbon emissions. The RFI highlights that the subsurface already hosts a wide range of naturally occurring reactions, from abiogenic methane formation to rare cases such as natural nuclear fission, and asks whether those natural conditions can be harnessed and scaled in a controlled way. ARPA-E points to several subsurface features that resemble conditions used in industrial chemistry: elevated temperatures common in deep geothermal settings (roughly 175 to 400 degrees F), high pressures that increase predictably with depth (on the order of 10 kPa per meter), and rocks that can contain catalytically relevant metals such as nickel and iron. The RFI notes that pressures used in major industrial processes are reachable at typical drilling depths; for example, around 400 atmospheres, comparable to pressures found at about 2 km depth, which is within the range of many existing subsurface operations.

Within that broader framing, ARPA-E is especially interested in two subsurface contexts for hydrogen generation. The first is hard rock systems, particularly old Precambrian formations that make up a large fraction of continental crust. In these settings, hydrogen can be produced naturally through radiolysis, where radiation from radioactive decay splits water to form hydrogen and oxygen, and through serpentinization, where iron-bearing mafic and ultramafic rocks react with water in redox processes that produce hydrogen. The RFI references published estimates suggesting that natural terrestrial hydrogen seepage could correspond to a wide range, roughly 0.1 to 33 percent of today's global fossil-based hydrogen production, while emphasizing that uncertainty in actual production rates is large. ARPA-E is looking for information on whether these reactions can be accelerated or sustained through stimulation methods (for example, by managing water availability, temperature, permeability, reactive surface area, or other controllable parameters) so the subsurface can function as a practical "georeactor" for clean hydrogen.

The second context is hydrocarbon-rich basins, where ARPA-E is exploring whether hydrogen could be produced by cracking hydrocarbons underground and bringing only hydrogen to the surface while leaving carbon in place. The motivation is to avoid the large carbon emissions associated with conventional surface hydrogen production, which today is dominated by steam methane reforming and coal gasification. The RFI cites typical emissions intensities on the order of about 9 tons of CO2 per ton of H2 for steam methane reforming and about 19 tons of CO2 per ton of H2 for coal gasification. ARPA-E frames subsurface hydrogen-from-hydrocarbons as a hypothesis that might reduce or eliminate the need for separate surface carbon capture and sequestration steps, potentially lowering cost and complexity. At the same time, the RFI is explicit that it is not yet clear whether this approach is technically feasible at meaningful scale, whether the necessary reaction control and gas separation can be achieved, and whether it can be economically competitive with surface hydrogen production paired with carbon capture and storage.

Because the envisioned end state involves not only generating hydrogen (and possibly helium) underground but also collecting and purifying it, the RFI also signals interest in enabling technical advances in subsurface gas handling and separations. That includes practical issues like how gases move through porous or fractured media, how to manage competing reactions and byproducts, how to avoid loss mechanisms, and how to selectively produce, extract, and separate hydrogen and helium from other subsurface gases under real field conditions. Overall, ARPA-E is trying to understand what breakthroughs would be needed to make subsurface chemical synthesis and gas production a credible new clean energy pathway, and what the most promising technical routes, target formations, and development milestones might look like.

Administrative details in the notice clarify that this is an RFI under Funding Opportunity Number DE-FOA-0002786 (CFDA 81.135) issued by ARPA-E within DOE. There is no award ceiling and no expected number of awards because no funding is being offered through this RFI. Eligibility is described as unrestricted for providing information, meaning any type of entity may respond subject to any clarifications in the full RFI text. Responses were requested as PDFs submitted by email to ARPA-E-RFI@hq.doe.gov, with the deadline listed as 5:00 p.m. Eastern Time on July 11, 2022. The full RFI text and instructions were made available through the ARPA-E funding opportunity website (arpa-e-foa.energy.gov).

• The Department of Energy, Advanced Research Projects Agency Energy in the opportunity zone benefits, science and technology and other research and development sector is offering a public funding opportunity titled "Request for Information (RFI): Stimulating Geochemical Reactions in the Subsurface for in-situ Generation of Hydrogen and Helium Production" and is now available to receive applicants.
• Interested and eligible applicants and submit their applications by referencing the CFDA number(s): 81.135.
• This funding opportunity was created on May 23, 2022.
• Applicants must submit their applications by Jul 11, 2022 Reponses to this RFI should be submitted in PDF format to the email address ARPA-E-RFI@hq.doe.gov by 500 p.m. Eastern Time on 7/11/2022. For further instruction, please review the RFI in its entirety at https://apra-e-foa.energy.gov.. (Agency may still review applications by suitable applicants for the remaining/unused allocated funding in 2026.)
• Eligible applicants include: Unrestricted (i.e., open to any type of entity above), subject to any clarification in text field entitled Additional Information on Eligibility.

Apply for DE FOA 0002786

[Watch] Creating a grant proposal using the step-by-step wizard inside the applicant portal: