Hydrogen Production by Underground Gasification of Fossil Fuel Resources
A&A Consulting Services for Underground Coal Gasification (UCG) and In-Situ Gasification of Fossil Fuel Resources — Site Characterization, Process Design, and Project Development for Syngas and Hydrogen Production — Worldwide
Assign your company's most challenging underground gasification projects to A&A, and let the high-level, seasoned UCG consultants of the A&A Consulting Team — with hands-on underground coal gasification pilot-test experience dating back to the 1970s — find the most appropriate solutions for you, around the world.
Dr. Jay Avasthi and other high-level, seasoned consultants of the A&A Consulting Team were directly involved in conducting Underground Coal Gasification (UCG) pilot tests in Rawlins, Wyoming, U.S.A., during the 1970s and 1980s, while employed by Gulf Oil Corporation (later acquired by Chevron Corporation). They have authored and co-authored several technical papers on various aspects of those pilot tests, published in peer-reviewed technical journals and in UCG Symposium proceedings — hands-on underground gasification experience that very few consulting teams anywhere in the world can offer.
Underground gasification is again drawing major investment. In 2025, Reliance Industries Ltd announced plans to develop India's first integrated Underground Coal Gasification complex, in Eluru district, Andhra Pradesh — a project reported at ₹2.73 lakh crore over its roughly 30-year life, with exploration beginning in the third quarter of 2026 — as part of India's National Coal Gasification Mission, which targets 100 million tonnes of coal gasification capacity by 2030. Underground gasification lets a company recover energy value from coal and other fossil-fuel resources too deep, thin, or otherwise uneconomical to mine by conventional methods, producing a syngas that can be converted to hydrogen, used directly for power generation, or processed into other chemicals and fuels.
Avasthi & Associates, Inc. (A&A) is an independent petroleum engineering and geoscience consulting firm. A&A does not sell gasification equipment, downhole tools, or syngas-processing technology — our only business is expert technical consulting, which means A&A's underground gasification recommendations are never influenced by a stake in any particular technology or vendor.
If your company is considering hydrogen, syngas, or power production by underground gasification of coal or other fossil-fuel resources, please contact us — the high-level, seasoned UCG consultants, subject-matter experts (SMEs), of the A&A Consulting Team, and collaborators, are available to help you on your challenging projects, around the world.
Related A&A Service: This page is one of nine services under A&A's broader energy transition practice — for A&A's full energy storage, hydrogen, ammonia, lithium, and geothermal service directory, please see A&A's Energy Transition & Decarbonization Consulting page.
1. What Is Underground Gasification?
Underground gasification converts a coal or other fossil-fuel resource into syngas — a mixture of hydrogen, carbon monoxide, methane, and carbon dioxide — in place underground, without physically mining or extracting it. Injection wells deliver an oxidant (air, oxygen, or steam) to ignite and sustain a controlled gasification reaction within the target resource, and production wells recover the resulting syngas at surface, where it can be processed into hydrogen, used directly for power generation, or converted into other chemicals and fuels. Because the resource is never physically mined, underground gasification can economically recover energy value from coal seams and other fossil-fuel resources that are too deep, too thin, or otherwise too uneconomical to mine by conventional methods.
2. Resource and Site Characterization
• Candidate Resource Screening: screening candidate coal seams or other fossil-fuel resources against depth, thickness, rank, and permeability criteria suited to underground gasification
• Geological and Hydrogeological Characterization: characterizing the target resource and surrounding strata, including the overlying and underlying aquifers that must be protected
• Site Selection: selecting candidate sites that balance resource quality against groundwater-protection, land-access, and surface-infrastructure constraints
3. Underground Gasification Process and Cavity Design
• Injection and Production Well Design: designing the injection and production well pattern and configuration that establishes and sustains the underground gasification reaction zone
• Gasification Process Design: selecting the oxidant (air, oxygen, or steam) and operating conditions needed to achieve the syngas composition and heating value your downstream use requires
• Cavity Growth and Reaction-Zone Modeling: modeling the growth, geometry, and stability of the underground gasification cavity over the project's operating life
4. Syngas and Hydrogen Production Pathways
• Syngas-to-Hydrogen Processing: designing the downstream shift-conversion and separation processes that convert underground-gasification syngas to hydrogen
• Power Generation and Chemicals Applications: evaluating direct power generation, synthetic natural gas (SNG), or chemicals and fuels production as alternative or complementary end uses for underground-gasification syngas
Related A&A Service: For A&A's full carbon capture and CO₂ storage consulting — to pair with underground-gasification syngas for low-carbon "blue" hydrogen production — please see A&A's Blue Hydrogen Consulting page.
5. Environmental Monitoring and Groundwater Protection
• Groundwater Monitoring Program Design: designing groundwater-quality monitoring programs to detect and manage any influence of the gasification process on surrounding aquifers
• Subsidence and Cavity-Stability Assessment: assessing subsidence risk and long-term underground-cavity stability
• Post-Operation Site Management: designing post-operation monitoring and site-closure plans
6. Project Development and Technical Advisory
• Technical and Economic Feasibility Studies: preliminary and detailed feasibility studies covering resource, process design, and project economics
• Pilot-Test Design and Oversight: designing and overseeing field pilot tests, drawing on A&A's own hands-on underground coal gasification pilot-test experience
• Investor-Grade Technical Due Diligence: independent technical due diligence for investors, partners, and lenders considering an underground gasification investment
• Environmental and permitting evaluation
• Risk assessment and mitigation planning
Software and Technical Tools
The high-level, seasoned UCG consultants of the A&A Consulting Team apply industry-standard geological, reservoir, and process-simulation software and technical tools to underground gasification studies, including:
• Petrel: for 3D geological modeling of the target resource and surrounding strata
• COMSOL: for coupled reactive-transport and thermal modeling of the underground gasification process
• Aspen HYSYS / Aspen Plus: for downstream syngas-to-hydrogen and chemicals process design
• Python and MATLAB: for data analytics and process optimization
Deliverables
The high-level, seasoned UCG consultants of the A&A Consulting Team deliver decision-grade technical and commercial intelligence for complex underground gasification projects, including, but not limited to:
• Full technical studies — resource characterization, process design, and environmental monitoring planning
• Pilot-test design, oversight, and interpretation
• Integrated techno-economic evaluation and risk analysis
• Independent technical due diligence for investors and lenders, and high-quality final reports and executive presentations
To put the high-level, seasoned UCG consultants, subject-matter experts (SMEs), of the A&A Consulting Team, and collaborators, to work on your company's challenging underground gasification projects, around the world, please contact us.
Frequently Asked Questions
What is Underground Coal Gasification (UCG), and how does it differ from conventional coal mining and gasification?
UCG gasifies coal in place underground — injecting an oxidant and recovering the resulting syngas through wells — rather than mining the coal and gasifying it at surface. This lets a project recover energy value from coal resources too deep, thin, or otherwise uneconomical to mine conventionally, without the cost, safety, and surface-disturbance considerations of physical mining.
Does A&A really have hands-on UCG pilot-test experience?
Yes. Dr. Jay Avasthi and other A&A consultants were directly involved in conducting UCG pilot tests in Rawlins, Wyoming, during the 1970s and 1980s while employed by Gulf Oil Corporation (later acquired by Chevron), and have authored and co-authored technical papers on those pilot tests published in peer-reviewed journals and UCG Symposium proceedings.
Can underground-gasification syngas be used to produce low-carbon "blue" hydrogen?
Yes. Underground-gasification syngas can be converted to hydrogen and paired with carbon capture and permanent CO₂ storage to produce low-carbon "blue" hydrogen — please see A&A's Blue Hydrogen Consulting page for A&A's full carbon capture and CO₂ storage consulting services.
What are the main environmental considerations for a UCG project?
Protecting surrounding groundwater from any influence of the gasification process is the central environmental consideration, along with managing subsidence risk and underground-cavity stability during and after operation. A&A's site-characterization and environmental-monitoring services are built around these considerations from the earliest stage of a project.
Is underground gasification only for coal?
Coal is the most common target resource, and the one A&A's consultants have direct pilot-test experience with, but the same underground gasification principles can apply to other fossil-fuel resources in appropriate geological settings. A&A's resource-screening services can help evaluate whether a specific resource is a suitable underground-gasification candidate.
Does A&A sell gasification equipment?
No. A&A is an independent petroleum engineering and geoscience consulting firm and does not sell gasification equipment, downhole tools, or syngas-processing technology, so A&A's recommendations are never influenced by a stake in any particular technology or vendor.
