A first ammonia-fuelled vessel carrying the gas as cargo could become a reality in the next 10 years, according to a team of Dutch naval architects.

C-Job Naval Architects lead naval architect Niels de Vries, who headed a research team, told TradeWinds that the company is now exploring options with potential shipowners on what using ammonia as bunkers might mean for their vessels and operations.

In the report titled “Safe and effective application of ammonia as a marine fuel” released today, the Dutch architects and their partners — chemical engineer Proton Ventures and venture backer Enviu — examine how ammonia can be used as bunkers to reduce greenhouse gas emissions.

Optimal solution

The report explains their concept design for a 54,000-dwt ammonia carrier fuelled by its own cargo and concludes that, at present, the optimal solution would be for this to be driven by an internal combustion engine that could burn ammonia or marine diesel.

De Vries believes power-cell technology will eventually be available as an alternative but says this is not yet accessible.

The team based its calculations on using green ammonia, which would be sourced from renewable hydrogen.

Ammonia is free from SOx and particulate matter and, if sourced from renewable hydrogen, would also be CO2-free in the whole supply-consumption chain. The application of ammonia in fuel cells is free from NOx.

Niels de Vries Photo: C-Job Naval Architects

De Vries said he has been conservative in his costings but prices green ammonia at about €850 ($963) per tonne, which he believes is slightly more than three times the cost of low-sulphur fuel oil — although he expects ammonia costs to reduce over time.

To justify the higher costs, a shipowner will either need a cargo owner who will pay more for clean transport, for alternative fossil fuels to become more expensive, or greener electricity to be more available.

Bottleneck

“Renewable energy production is the bottleneck at the moment,” he said.

On concerns regarding ammonia’s toxicity, De Vries said proper detection and adequate ventilation are needed to ensure this is handled correctly. Remotely operated shut-off valves would also be needed to handle leaks.

I don’t think there will be a single fuel. They should supplement each other rather than shoot each other. The only that should be shot is fossil fuels

Niels de Vries

Ammonia’s high flammability is another issue addressed in the concept vessel’s design.

“We see ammonia as one of the high potentials of the renewable fuels,” De Vries said. “We definitely do not exclude other options.”

The research chief said that, for the future, he sees a combination of hydrogen, ammonia and methanol working together in the same way gasoline and diesel do now.

Ship type, operational profile, local infrastructure and other factors will influence fuel preferences.

“I don’t think there will be a single fuel,” he said. "They should supplement each other rather than shoot each other. The only [one] that should be shot is fossil fuels.”