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Displacing fishmeal with protein derived from stranded methane


Methane emitted and flared from industrial sources across the United States is a major contributor to global climate change. Methanotrophic bacteria can transform this methane into useful protein-rich biomass, already approved for inclusion into animal feed. In the rapidly growing aquaculture industry, methanotrophic additives have a favourable amino acid profile and can offset ocean-caught fishmeal, reducing demands on over-harvested fisheries. Here we analyse the economic potential of producing methanotrophic microbial protein from stranded methane produced at wastewater treatment plants, landfills, and oil and gas facilities. Our results show that current technology can enable production, in the United States alone, equivalent to 14% of the global fishmeal market at prices at or below the current cost of fishmeal (roughly US$1,600 per metric ton). A sensitivity analysis highlights technically and economically feasible cost reductions (such as reduced cooling or labour requirements), which could allow stranded methane from the United States alone to satisfy global fishmeal demand.

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Fig. 1: Process model for methanotrophic biomass production.
Fig. 2: Methane sources and capture potential.
Fig. 3: Levelized cost of methanotrophic microbial protein across baseline scenarios in which methane comes from wastewater treatment, landfills, oil and gas facilities, and the natural gas grid.
Fig. 4: Supply curve for methanotrophic production using stranded methane.
Fig. 5: Sensitivity analysis for baseline methanotroph production at landfills, individually varying the parameters to low and high values.

Data availability

The data used in the analysis and figures are publicly available. The data on flaring from oil and gas facilities are available through the Earth Observation Group ( All data on methane emissions from oil and gas facilities and landfills, flaring from landfills, and unit processes at wastewater treatment plants are available from the US EPA through the following programmes: Facilities Level Information on GreenHouse gases Tool (, Landfill Methane Outreach Program ( and Clean Watersheds Needs Survey for 2004 (, 2008 ( and 2012 (

Code availability

Code supporting the current study is available at


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This study was funded by the Stanford Center for Innovation in Global Health (S.H.E., C.S.C. and S.P.L.) and the Stanford Natural Gas Initiative (S.H.E., E.D.S., C.S.C. and A.R.B.), an industry consortium that supports independent research at Stanford University. We thank R. Hickey for input on industrial bioreactor scaling.

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Authors and Affiliations



S.H.E. and E.D.S. conceptualized the project. S.H.E. and E.D.S. devised the methodology with feedback from A.R.B., C.S.C. and S.P.L. S.H.E. and E.D.S. validated the methodology, conducted the investigation and wrote the original draft of the paper. S.H.E., E.D.S., A.R.B., S.P.L. and C.S.C. reviewed and edited the paper. E.D.S., A.R.B. and C.S.C. supervised the project. S.H.E. and E.D.S. conducted the project administration. S.H.E., E.D.S., A.R.B., S.P.L. and C.S.C. acquired the funding.

Corresponding author

Correspondence to Craig S. Criddle.

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The authors declare no competing interests.

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Peer review information Nature Sustainability thanks Richard Cottrell, Richard Newton and Jo De Vrieze for their contribution to the peer review of this work.

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Supplementary information

Supplementary Information

Supplementary Tables 1–14, Figs. 1–7, Notes 1–3 and Methods.

Reporting Summary

Supplementary Data 1

Raw data for Figs. 2 and 4, including the methane source size for each point source in the analysis, the corresponding amount of methanotrophic SCP that can be produced from the source and the model output for the cost of SCP (US$ per ton) for production at the location.

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El Abbadi, S.H., Sherwin, E.D., Brandt, A.R. et al. Displacing fishmeal with protein derived from stranded methane. Nat Sustain 5, 47–56 (2022).

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