Upstream considerations for gas fermentation processes

Resch, Michael G. [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] (ORCID:0000000280715764); Badgett, Alex [National Renewable Energy Laboratory (NREL), Golden, CO (United States)]; Krömer, Jens O. [Helmholtz Centre for Environmental Research, Leipzig (Germany)] (ORCID:0000000150060819); Marcellin, Esteban [Univ. of Queensland, St. Lucia, QLD (Australia)]

doi:10.1016/j.copbio.2025.103337

DOE OSTI · 2575623

Upstream considerations for gas fermentation processes

Resch, Michael G. [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] (ORCID:0000000280715764)·Badgett, Alex [National Renewable Energy Laboratory (NREL), Golden, CO (United States)]·Krömer, Jens O. [Helmholtz Centre for Environmental Research, Leipzig (Germany)] (ORCID:0000000150060819)·Marcellin, Esteban [Univ. of Queensland, St. Lucia, QLD (Australia)]

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Abstract

Gas fermentation enables the production of fuels, chemicals, and foods from gaseous carbon sources and could serve as a technology for valorizing carbon that may otherwise be emitted to the atmosphere. In this review, we focus on upstream feedstock considerations: the supply of carbon and the supply of electrical power. Electrical power serves a dual role, providing both process energy and biochemical redox potential (via hydrogen or reduced intermediates). We define gas fermentation as bioprocesses involving gaseous feedstocks metabolized by microbes, distinct from microbial electrosynthesis. Trends in CO 2 point sources and low-carbon electricity systems are analyzed, highlighting opportunities and challenges for future deployment. This review synthesizes current knowledge and identifies key R&D priorities for process integration at industrial scale.

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09 BIOMASS FUELS 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY CO2 electrochemistry energy gas fermentation grid

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Resch, Michael G. [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] (ORCID:0000000280715764), Badgett, Alex [National Renewable Energy Laboratory (NREL), Golden, CO (United States)], Krömer, Jens O. [Helmholtz Centre for Environmental Research, Leipzig (Germany)] (ORCID:0000000150060819), Marcellin, Esteban [Univ. of Queensland, St. Lucia, QLD (Australia)]. 2025-07-29. Upstream considerations for gas fermentation processes. https://doi.org/10.1016/j.copbio.2025.103337

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