Issue 5, 2021

Can sustainable ammonia synthesis pathways compete with fossil-fuel based Haber–Bosch processes?

Abstract

As renewable electricity prices continue to decline, interest grows in alternative routes for the synthesis of sustainable fuels and chemicals, including ammonia. Considering demand for fertilizers, as well as its future potential as a dispatchable energy vector, sustainable synthesis of ammonia is being explored as an alternative to the capital- and carbon-intensive fossil-fuel-driven Haber–Bosch process. Here we assess stages along a transition to the sustainable synthesis of ammonia, looking at economic feasibility and climate impacts compared to the incumbent Haber–Bosch without and with CO2 capture. This analysis enables us to suggest technological thresholds for sustainable synthesis of ammonia to become economically and environmentally favourable. When driven by renewable energy sources, the water electrolyzer (near $400 per kW) coupled Haber–Bosch process will reach cost parity near 2.5 cents per kWh electricity. In the case of direct electrochemical ammonia synthesis, achieving cost-parity using the same 2.5 cents per kWh electricity will rely on achieving major advances in performance: an electrolysis full-cell energy efficiency exceeding 40% at a current density of 0.5 A cm−2. Once this operating performance is reached, electrically-powered ammonia synthesis will bring climate benefits when coupled with low-carbon electricity (<180 gCO2e per kWh), achievable when over half of today's U.S. electricity generation is supplied by renewable energy sources. We conclude with a forward-looking perspective on the key challenges and opportunities for sustainable ammonia synthesis routes to be competitive with the incumbent Haber–Bosch process in the future.

Graphical abstract: Can sustainable ammonia synthesis pathways compete with fossil-fuel based Haber–Bosch processes?

Supplementary files

Article information

Article type
Analysis
Submitted
03 ডিসে. 2020
Accepted
22 মার্চ 2021
First published
23 মার্চ 2021

Energy Environ. Sci., 2021,14, 2535-2548

Can sustainable ammonia synthesis pathways compete with fossil-fuel based Haber–Bosch processes?

M. Wang, M. A. Khan, I. Mohsin, J. Wicks, A. H. Ip, K. Z. Sumon, C. Dinh, E. H. Sargent, I. D. Gates and M. G. Kibria, Energy Environ. Sci., 2021, 14, 2535 DOI: 10.1039/D0EE03808C

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements