Ammonia: fertiliser today, hydrogen carrier tomorrow

Ammonia is one of the most quietly important molecules on the planet. It feeds roughly half the world through fertiliser, and it may soon become the cleanest practical way to carry hydrogen across an ocean. The same properties that make it useful also make it demanding to handle, which is exactly where a trading and shipping desk earns its keep.

The fertiliser workhorse

Ammonia is nitrogen and hydrogen, NH3, made by combining the two under heat and pressure in the Haber-Bosch process. That reaction is more than a century old and it underpins modern agriculture. The world produces on the order of 180 million tonnes of ammonia a year, and the large majority of it goes into nitrogen fertilisers such as urea. Without it, global food output would be a fraction of what it is.

Today most ammonia is made from natural gas, which is why the industry sometimes calls it grey ammonia. That also ties its cost closely to the gas price, a link every fertiliser buyer learned to watch when gas markets turned volatile. It already trades and ships globally, with dedicated terminals and a fleet of gas carriers built to handle it, so the logistics network the future will lean on is not new. It exists now.

Ammonia as a hydrogen carrier

Hydrogen is a promising clean fuel, but it is a nightmare to move. As a liquid it has to be chilled to minus 253 degrees, close to absolute zero, which is costly and leaky at scale. Ammonia offers a way around that. Each molecule already holds three hydrogen atoms, so ammonia is around 17 to 18 percent hydrogen by mass, and it turns liquid at a far gentler minus 33 degrees at atmospheric pressure. That makes it far easier to store and ship in volume.

At the destination there are two paths. You can crack the ammonia back into hydrogen and nitrogen for use in fuel cells or industry, or you can burn the ammonia directly. Japan and South Korea are already testing ammonia co-firing in power stations, and it is being trialled as a marine fuel for the same ships that might one day carry it. Made with renewable electricity instead of gas, so-called green ammonia, the whole chain can carry clean energy from a windy or sunny coast to a demand centre with no easy renewables of its own.

• Around 17 to 18 percent hydrogen by mass, and liquid at a manageable minus 33 degrees.
• Two uses at the far end: crack it back to hydrogen, or burn the ammonia directly for power or propulsion.
• An existing global trade in fertiliser ammonia gives the energy version a head start on ports and ships.

The fuel of the future may travel in a molecule farmers have shipped for a hundred years.

The handling challenge

None of this is free of risk. Ammonia is toxic and corrosive, and a release is dangerous to people and equipment alike. It demands trained crews, tight materials selection, careful ventilation, and terminals built and inspected to a high standard. Burned as a fuel it can also produce nitrogen oxides and, if the combustion is poor, unburnt ammonia, so the emissions side has to be engineered as carefully as the energy side. These are solvable problems, and the industry has decades of experience solving them, but they are the reason ammonia is a specialist cargo rather than a casual one.

For Cheka the appeal is that the discipline is familiar. Moving a hazardous liquid to spec, under inspection, with the right vessel and the right paperwork, is the core of what a product desk already does. Ammonia simply raises the stakes and, as the hydrogen economy grows, the reward.