Maritime is certainly targeting green ammonia as a future fuel to meet decarbonisation goals, but regulators say many unknowns still linger.
Aside from being virtually carbon-free and abundant in supply, not much else is known about how it would work out as a safe bunker fuel for vessels at sea, said Ulrik Frorup, commercial director for marine and offshore at classification society Bureau Veritas.
“We have to remember that we are on a learning curve when it comes to ammonia,” he told TradeWinds. “We are not yet at the point where we are ready to navigate a vessel with ammonia. Let’s be frank.”
Bureau Veritas is studying the potential fuel source because, one day, it will have to consider it in its classifications as maritime strives to reduce greenhouse gas emissions by 40% by 2030 and 70% by 2050 — as mandated by the International Maritime Organization.
But Frorup said Bureau Veritas — one of the world’s largest classification societies — still needs prototype two-stroke engines just to test ammonia’s safety and efficacy as a viable marine fuel.
Bureau Veritas does not expect those engines, which will help reveal emission levels under various cargo weights and sizes, to come into being until 2024.
“Then we would start to look into all these issues that are a bit difficult to do on paper,” he said.
“After that, we will be more prepared to go even deeper into the [IMO] requirements.”
He said Bureau Veritas believes engine design can lower ammonia’s NOx emissions to below the IMO’s limits, but the vessels must be able to prevent ammonia from entering the sea.
“The key challenge is the toxicity,” he said. “Ammonia is already well known by the maritime business because we have vessels transporting it.”
He said any pipes carrying ammonia, which the IMO considers a marine pollutant, must be double-walled to prevent leakage, and holding tanks must have pressure valves to avoid spontaneous combustion.
Bureau Veritas also needs to factor in other aspects with ammonia as a future fuel for maritime, such as the need for a pilot fuel because, when not under great pressure, ammonia is actually non-flammable.
“The ammonia is not particularly easy to burn, so you will have to switch to some other means of fuel oil,” he said.
“It’s important that we keep that in mind, that we can have the time to do this correctly. We will get there.”
