Molecules
Ammonia NH₃
The only hydrogen carrier with a century-old production industry and an existing global shipping trade. That is its decisive advantage.
The carrier that already ships
What it is
Ammonia is hydrogen and nitrogen, synthesised industrially at scale since the early twentieth century via the Haber-Bosch process. It carries about 17.8% hydrogen by mass, liquefies at around −33 °C at atmospheric pressure or under modest pressure at ambient temperature, and is already produced, stored and shipped globally in large volumes — which means terminals, vessels, handling standards and a trained workforce already exist.
How it is produced
Haber-Bosch with electrolytic hydrogen
Conventional synthesis fed by hydrogen from electrolysis and nitrogen from air separation. The process is mature; the new engineering problem is running it flexibly against a variable renewable supply.
Haber-Bosch with reformed hydrogen and capture
The incumbent route with CO2 capture added. Ammonia plants produce a relatively concentrated CO2 stream, which makes capture comparatively straightforward.
Conventional Haber-Bosch
The unabated incumbent, overwhelmingly fed by reformed natural gas and responsible for a significant share of global industrial emissions.
Direct electrochemical synthesis
Producing ammonia electrochemically without a separate hydrogen step. Research stage, with efficiency and selectivity the central problems.
Conversion
Ammonia can be cracked back into hydrogen and nitrogen, typically at around 400–600 °C over a catalyst, with purification afterwards to reach fuel-cell-grade hydrogen. Cracking consumes a meaningful fraction of the delivered energy, so the economics favour using ammonia directly as ammonia wherever the end use allows.
Storage
Refrigerated at around −33 °C in large atmospheric tanks, the established approach for bulk storage at production sites and import terminals, or pressurised at ambient temperature for smaller volumes. Both are long-standing industrial practice with mature standards.
Transport
Shipped in liquefied gas carriers, moved by pipeline, rail and road, and handled at existing ammonia terminals. Ammonia's established trade is the main reason it is the leading candidate for intercontinental hydrogen-equivalent transport — the infrastructure question is largely one of scale rather than of invention.
Infrastructure
Synthesis plant, air separation, refrigerated storage, jetty and loading systems, shipping and import terminals. Existing fertiliser trade infrastructure provides a genuine head start, though terminals designed for fertiliser import are not automatically suitable for bunkering or for large-scale energy import.
Economics
Cost is dominated by the hydrogen input, so ammonia economics largely follow hydrogen economics with synthesis capital and energy added. Its advantage is on the delivery side: lower transport and storage cost per unit of delivered energy than liquid hydrogen over long distances, against existing infrastructure. Where the end use can consume ammonia directly, avoiding cracking materially improves the case.
Applications
- Fertiliser — by far the largest existing market
- Marine fuel, as one of the leading candidates for deep-sea shipping decarbonisation
- Hydrogen carrier for intercontinental transport, cracked at the destination
- Co-firing in coal power plants, particularly in Japan and Korea
- Industrial feedstock for nitric acid, explosives and chemicals
Commercial challenges
- Toxicity requires careful handling, and public acceptance work for new uses such as bunkering
- Cracking losses undermine the case where hydrogen is the actual end product
- Engine and combustion technology for marine use is still maturing
- NOx and nitrous oxide emissions management in combustion applications
- Certification of low-carbon ammonia differs between importing markets
Questions
Why is ammonia considered the leading hydrogen carrier?
Because it is the only candidate with an existing global production and shipping industry. Vessels, terminals, storage, handling standards and skilled operators already exist at scale, which removes a large part of the infrastructure risk that liquid hydrogen and novel carriers still carry.
Is it better to use ammonia directly or crack it back to hydrogen?
Directly, wherever the end use permits — as fertiliser, as marine fuel or for co-firing. Cracking consumes a significant share of the delivered energy plus purification cost, so it only makes sense where the customer genuinely requires hydrogen.
What makes ammonia green or low-carbon?
The carbon intensity of the hydrogen feedstock, and increasingly the accounting rules of the certification scheme in the destination market. Electrolytic hydrogen from renewable power gives the lowest intensity; reformed hydrogen with capture gives an intermediate figure that depends on capture rate and upstream methane emissions.
Where ammonia matters
How we can help
Offtake & Buyer Discovery
Finding and qualifying the buyers a production project needs to be financeable.
Read more →Techno-Economic Analysis
Levelised cost modelling with the assumptions exposed and the sensitivities tested.
Read more →Market Analysis
Who is buying, who is selling, at what price, along which corridors — and where that leaves you.
Read more →Working with ammonia?
Whether you produce it, buy it, build for it or are deciding whether it fits your region, the starting point is the same conversation.