During development of the technical aspects of any energy project, a social perspective needs to be considered. Public opinion is going to be a fundamental parameter to determine the role of renewables in the future, with decarbonisation meaning innovation towards a comprehensive plan that involves not only technology but also psychology and how these two can benefit from each other.
Due to the importance of understanding public perception of ammonia, Cardiff University conducted a study focused on the Yucatan Peninsula, Mexico, which currently presents high revenues in agriculture and depends on ammonia as a fertiliser. An analysis of stakeholder’s perception of ammonia was carried out to understand the different barriers and drivers of each established group.
At the 2017 NH3 Energy+ Conference, graduate student Doga Demirhan reported on an ongoing investigation at the Energy Institute at Texas A&M University. The work involved evaluation of options for an ammonia production system and concluded that biomass could be an economically viable feedstock under current, real-world conditions. This is a notable outcome. Just as notable is how it was reached.
A new study examines the technologies needed to produce renewable ammonia from offshore wind in the US, and analyzes the lifetime economics of such an operation.
This is the latest in a years-long series of papers by a team of researchers from the University of Massachusetts, Amherst, and Massachusetts Institute of Technology (MIT). And it is by far the closest they have come to establishing sustainable ammonia as being cost-competitive with fossil ammonia.
The U.S. Department of Energy H2@Scale program’s November 2017 workshop in California included mention of ammonia as a constituent of a future hydrogen economy. It also highlighted the relevance ammonia energy could have in California.
California stands out globally as a large economy that is strongly committed to development of a hydrogen economy. The state’s strategy for hydrogen-powered transportation involves reducing the production cost of renewable hydrogen and the capital and operating costs of hydrogen fueling stations. It does not explicitly address the cost of intermediate hydrogen logistics.
The question of cost is of utmost importance because California has so far put $120 million of public funds into hydrogen fueling stations and intends to invest an additional $20 million per year through 2022. The state’s aspiration is to move to a point where hydrogen that is used as a motor fuel is free of public subsidy. So it clearly behooves the state to investigate how ammonia could be used as a cost-reducing energy carrier.
Toyota is active in California’s hydrogen movement and has announced plans to build a renewable hydrogen plant that will use cow manure as a feedstock. A project with a different conception, one that draws upon the solar and wind resources of the Mojave Desert to produce renewable hydrogen and logistically advantaged ammonia, would align better with the state’s sustainability objectives.
The list of investment drivers for building new ammonia plants in the US over the last few years was short, beginning and ending with cheap natural gas. Markets change, however, and the investment drivers for the next generation of new ammonia plants might include low cost electrolyzers, low cost renewable power, carbon taxes, and global demand for ammonia as a carbon-free energy vector.
For this to make sense, however, ammonia needs to be produced without fossil fuel inputs. This is perfectly possible using Haber-Bosch technology with electrolyzers, but today's wind and solar power plants exist on a smaller scale than could support a standard (very big) Haber-Bosch plant. So, to produce renewable ammonia, small-scale ammonia production is essential.
This time series chart shows the capital intensity of today’s ammonia plants. Together, the data illustrate competitive advantages of alternative investment strategies, and demonstrate a shift away from the prior trend toward (and received wisdom of) monolithic mega-plants that rely on a natural gas feedstock.
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.
Last week, in Part 1 of this series on electrochemical ammonia synthesis technologies, I quoted a recent article by researchers at MIT that identified avenues for future research and development. One option was a biomimicry approach, learning from "enzymatic catalysts, such as nitrogenases," which can "either be incorporated into or provide inspiration for the design of electrocatalytic processes."
The nitrogenase enzyme, nature's ammonia synthesis technology, was developed in an iterative innovation process, otherwise known as evolution, that took hundreds of millions of years to reach this level of efficiency. According to one group of electrochemists, who presented their results at the recent NH3 Energy+ conference, nitrogenase produces ammonia in nature with an enviable 75% process efficiency - so it's no surprise that they are basing their industrial technology on it.
Last month's NH3 Energy+ conference featured presentations on a great range of novel ammonia synthesis technologies, including improvements to Haber-Bosch, and plasmas, membranes, and redox cycles. But, in a mark of a conference approaching maturity, members of the audience had at least as much to contribute as the presenters.
This was the case for electrochemical synthesis technologies: while the presentations included updates from an influential industry-academia-government collaboration, led by Nel Hydrogen's US subsidiary, the audience members represented, among others, the new electrochemical ammonia synthesis research lab at Massachusetts Institute of Technology (MIT), and a team from Monash University in Australia. The very next week, Monash published its latest results, reporting an electrochemical process that synthesized ammonia with 60% faradaic efficiency, an unprecedented rate of current conversion at ambient pressure and temperature.
Speaking at the NH3 Energy+ Topical Conference last month, University of Delaware Adjunct Professor Shimshon Gottesfeld reported on progress made by the university’s direct ammonia fuel cell (DAFC) project. Evidently, the UDel team is now a big step closer to its goal of establishing the DAFC as a viable automotive power plant.
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.