This series of articles on the future of ammonia synthesis began with a report on the NH3 Energy+ conference presentation by Grigorii Soloveichik, Program Director at the US Department of Energy's ARPA-E, who categorized the technologies as being either improvements on Haber-Bosch or electrochemical (with exceptions).
ARPA-E invests in "transformational, high-risk, early-stage research," and recently began funding ammonia synthesis technologies, not to make renewable fertilizer but to produce "energy-dense zero-carbon liquid fuel." This article will introduce the six electrochemical technologies currently in development with funding from ARPA-E.
I wrote recently about two pathways for ammonia production technology development: improvements on Haber-Bosch, or electrochemical synthesis.
Last week, I covered some of these Haber-Bosch improvements; next week, I'll write about electrochemical processes. This week, I want to write about some innovations that don't fit this two-way categorization: they don't use electrochemistry and they don't build upon the Haber-Bosch process, and that might be the only thing that links them.