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  • Perspective
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Offshore green ammonia synthesis

Abstract

The global potential for renewable energy production far exceeds global energy demand. However, the accessibility of renewable energy is constrained by existing land use, the need to preserve protected areas and the costs associated with transporting energy over large distances. As a consequence, finite renewable energy capacity must be carefully matched to appropriate end uses. In this Perspective, we advocate the production of green ammonia on the ocean to address this policy challenge: local renewables should be used to generate electricity with high efficiency, whereas comparatively low-efficiency chemical energy storage in the form of ammonia should occur further away from energy consumers and be transported at relatively low costs. We describe the synthesis processes to be adopted, the techno-economic basis for this resource allocation, and the technical developments required that can enable this energy system to be established.

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Fig. 1: Land availability in Western Europe.
Fig. 2: Concept for ammonia production far offshore.
Fig. 3: Four synthesis concepts for offshore ammonia generation.

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Acknowledgements

This work was supported financially by the Rhodes Trust.

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Both authors contributed to the conceptualization of the research. N.S. performed the analysis and led the writing of the manuscript. R.B.-A. provided input and helped to write the manuscript.

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Correspondence to René Bañares-Alcántara.

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Salmon, N., Bañares-Alcántara, R. Offshore green ammonia synthesis. Nat. Synth 2, 604–611 (2023). https://doi.org/10.1038/s44160-023-00309-3

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