New data from a number of ammonia energy safety studies will be published later this year. In the meantime, two excellent reports already exist that provide comparative, quantitative risk analyses. Each compares the risks of using ammonia as a fuel in passenger vehicles against the risks of other fuels, including gasoline, LPG, CNG, methanol, and hydrogen. Both conclude that the risks associated with using ammonia as a fuel are "similar, if not lower than for the other fuels."
The second annual Power to Ammonia conference, which took place earlier this month in Rotterdam, was a tremendous success. It was again hosted by Proton Ventures, the Dutch engineering firm and mini-ammonia-plant pioneer, and had roughly twice as many attendees as last year with the same extremely high quality of presentations (it is always an honor for me to speak alongside the technical wizards and economic innovators who represent the world of ammonia energy).
However, for me, the most exciting part of this year's event was the fact that, for the first time at an ammonia energy conference, all four of the major ammonia technology licensors were represented. With Casale, Haldor Topsoe, ThyssenKrupp, and KBR all developing designs for integration of their ammonia synthesis technologies with renewable powered electrolyzers, green ammonia is now clearly established as a commercial prospect.
Japanese manufacturing concern IHI reported on May 16 that it had “successfully generated 1 kW class power” from a direct ammonia solid oxide fuel cell. This is the latest milestone for a technology that could play a major role in the roll-out of Japan’s Hydrogen Society.
At last week’s Australian Petroleum Production and Exploration Association Conference, Woodside Petroleum’s chief executive officer Peter Coleman spoke about the “huge” opportunity in hydrogen energy that will develop for the company over the next 10-15 years. Coleman sees the Japanese market for hydrogen as a promising destination for Woodside’s substantial reserves of natural gas, and indicated the company is evaluating alternative methods of hydrogen transport including as liquid H2, a liquid organic hydride, and ammonia.
Over the last few years, world-scale ammonia plants have been built, restarted, and relocated across the US. The last of these mega-projects began operations at Freeport in Texas last month. No more new ammonia plants are currently under construction in the US, and the received industry wisdom is that no more will begin construction.
However, project developers and ammonia start-ups did not get this memo. With low natural gas prices persisting, they have not stopped announcing plans to build new plants. The difference is that the next tranche of new ammonia plants breaking ground will not be world-scale but regional-scale, with production capacities of perhaps only one tenth the industry standard. Despite using fossil feedstocks, these plants will set new efficiency and emissions standards for small-scale ammonia plants, and demonstrate novel business models that will profoundly alter the future industry landscape for sustainable ammonia technologies.
The United States Congress passed a measure on February 9 that could galvanize the production of low-carbon ammonia in the U.S. The measure, included within the Bipartisan Budget Act of 2018, amends Section 45Q of the Internal Revenue Code, titled “Credit for Carbon Dioxide Sequestration”. That section, originally adopted in 2008, created a framework of tax credits for carbon capture and sequestration. 45Q’s impact in the intervening years has been minimal, an outcome attributed by experts to the relatively low prices assigned to CO2 sequestration and the fact that tax credits would be allowed only for the first 75 million tonnes of sequestered CO2. The new legislation increases the tax credit per tonne of CO2 placed in secure geological storage from $20 to $50, and for CO2 used for enhanced oil recovery from $10 to $35. It eliminates the credits cap altogether. With these changes, it now seems possible that low-carbon ammonia could find itself on an equal economic footing with “fossil” ammonia – and this could have consequences well beyond American agricultural markets.
Toyota Motor Corporation announced on April 25 the launch of an effort called the Chita City and Toyota City Renewable Energy-Use Low-Carbon Hydrogen Project. According to the company’s press release, the project is intended as a step toward “the realization of a hydrogen-based society spanning the entire region through mutual coordination and all-inclusive efforts.”
For ammonia energy advocates, the announcement had two elements of particular significance. First is the clear indication that Toyota Motor Corporation is embracing ammonia as a hydrogen carrier – although not as a motor fuel. Second is the project’s stated intention to establish a “system in which Aichi Prefecture certifies low-carbon hydrogen objectively and fairly.”
The newest ammonia plant on the planet has opened in Freeport, Texas.
A joint venture between Yara and BASF, this world-scale ammonia plant uses no fossil fuel feedstock. Instead, it will produce 750,000 metric tons of ammonia per year using hydrogen and nitrogen delivered directly by pipeline. The plant's hydrogen contract is structured so that the primary supply is byproduct hydrogen, rather than hydrogen produced from fossil fuels, and therefore the Freeport plant can claim that its ammonia has a significantly reduced carbon footprint.
This new ammonia plant demonstrates three truths. First, low-carbon merchant ammonia is available for purchase in industrial quantities today: this is not just technically feasible but also economically competitive. Second, carbon intensity is measured in shades of grey, not black and white. Ammonia is not necessarily carbon-free or carbon-full, but it has a carbon intensity that can quantified and, in a carbon-constrained economy, less carbon content equates to higher premium pricing. Third, the ammonia industry must improve its carbon footprinting before it can hope to be rewarded for producing green ammonia.
Approximately 40% of the world’s energy budget is consumed in the generation of electricity. This is by far the largest use of primary energy across major energy-consuming sectors (transportation, industry, etc.). What role ammonia will play in the electricity sector is therefore a question of considerable importance for the sustainable energy system of the future. One concept currently on the table is power-to-ammonia as a means of electricity storage, whereby electricity is used to produce hydrogen and the hydrogen is reacted with nitrogen to produce ammonia. The other, mirror-image, concept is to use ammonia, or hydrogen derived from ammonia, as a fuel that can be turned into electricity.
This “back-end” use case is the focus of recent announcements from Mitsubishi Hitachi Power Systems (MHPS). According to an April 5 story in the Nikkei Sangyo, MHPS plans to put a “hydrogen-dedicated gas turbine . . . into practical use by 2030.” The company also stated that it has “started developing technology to extract hydrogen from ammonia,” citing ammonia’s ease “to store and transport.”
Last week, the International Maritime Organization (IMO) formally adopted its Initial GHG Strategy. This means that the shipping industry has committed to "reduce the total annual GHG emissions by at least 50% by 2050," and completely "phase them out, as soon as possible in this century."
This also means that a global industry is searching for a very large quantity of carbon-free liquid fuel, with a production and distribution infrastructure that can be scaled up within decades. The most viable option is ammonia. How much would be required? Roughly one million tons of ammonia per day.