Safety of Ammonia Energy: First Up, the Maritime Use Case?

By Stephen H. Crolius on November 07, 2019


Ammonia.  A hazardous chemical, no doubt.  But is it too hazardous to use as an energy vector?  This is a legitimate question that must be addressed as other aspects of the ammonia energy concept advance. It is also a question whose unique context can be evoked with two other questions: Haven’t the safety issues already been identified and resolved over the last 100 years of widespread agricultural and industrial use?  And even if they have, how will the general public react when proposals for expanded ammonia infrastructure suddenly appear?

The earliest tip of this particular iceberg came into view this year when the Dutch naval architecture firm C-Job (an Ammonia Energy Association member) released Safe and effective application of ammonia as a marine fuel, a thesis written by the firm’s Lead Naval Architect Niels de Vries. De Vries notes that the document is “the first known [public] risk analysis for an ammonia fuel system for a vessel.”  In the course of his analysis, he identified 61 possible failure modes for an ammonia-powered vessel, and then deemed 28 to represent risks that are “unacceptable.”  He then proposed a range of mitigation measures that could “brings the risks . . . to a lower tolerable and acceptable level.”  De Vries sees his work as “a valuable first step towards the application of ammonia as a marine fuel” but states that “a lot of additional research is still required to explore its full potential and feasibility.”

At almost the same moment, the International Energy Agency (IEA) published its groundbreaking report, The Future of Hydrogen.  This included a paragraph that asserted that ammonia generally raises more health and safety considerations than hydrogen, and its use would probably need to continue to be restricted to professionally trained operators. It is highly toxic, flammable, corrosive, and escapes from leaks in gaseous form.”  In response, Ammonia Energy published an open letter to the IEA expressing the opinion that “this description of ammonia’s hazard profile is inaccurate and unhelpful.”  This assertion was supported with a comparison of the hazard profiles of hydrogen and ammonia on the dimensions of toxicity, flammability, and corrosiveness.  Taking note of the fact that hydrogen has been deemed safe enough for the general public to engage in fueling operations for hydrogen-powered vehicles, the letter noted that “it will be interesting to see how the safety engineers position ammonia in comparison.”

The IEA did not respond to the letter, but word came back informally that an important stakeholder was extremely concerned about the use of ammonia fuel in one particular sector: ocean freight – further underscoring the value of de Vries’ thesis.

It is widely acknowledged within the ammonia energy community that the hazards of ammonia must be addressed in a serious manner.  This will entail a technical effort in which qualified engineers work to design facilities that meet safety standards defined by regulatory authorities.  But not just that.  Significant effort will also be needed in the realm of public opinion to distinguish ammonia’s real hazards from perceptions based on incomplete knowledge and conflation.



This article is part of our Annual Review 2019. To mark the third anniversary of Ammonia Energy, we are highlighting ten “tip-of-the-iceberg” topics that we’ve written about over the last 12 months. In each case, we think we see something just peeking above the current flow of events that is developing into a major phenomenon below the surface.

Read all the stories in our Annual Review 2019.