Energy Efficiency, Techno-Economic Viability, and Life Cycle Assessment of In-Situ Hydrogen Production from Natural Gas Reservoirs Using Electromagnetic Heating

Abstract Recently, a subsurface technology of in-situ hydrogen production using electromagnetic (EM) heating shows great potential for extracting clean hydrogen directly from natural gas reservoirs. However, critical knowledge gaps persist, particularly in technical assessments. This study addresses these gaps by evaluating energy efficiency, techno-economic viability, and greenhouse gas (GHG) emissions throughout the process. We analyze the system energy efficiency under various experimental conditions using sandstone and synthetic catalysts. The results highlight the potential for field improvements through the optimization of catalysts and methane flow rates. Techno-economic analysis (TEA), based on a developed reservoir-scale model, indicates hydrogen production cost can be potentially as low as $0.86/kg with the integration of renewable energy. Key cost drivers include membrane expenses and EM-heating electricity for hydrogen production. Life cycle assessment (LCA) indicates that methane pyrolysis in gas reservoirs does not generate GHG emissions throughout its life cycle. However, GHG emissions associated with electricity use (i.e., EM heating) in the process should be considered. Moreover, the technology's eligibility for Section 45 V of Inflation Reduction Act (IRA 45 V) clean hydrogen credits is contingent upon the source of electricity used. And the qualification for the credits depends on the proportion of renewable energy in the electricity consumption mix. This study provides insights into efficiency optimization, cost competitiveness, and environmental considerations for in-situ hydrogen production from gas reservoirs using EM heating.