With one or two exceptions, the majority of shipowners were sceptical about autonomous vessels three years ago, says Rolls-Royce marine director of engineering and technology Kevin Daffey.

But he says opinion has been shifting, with “most companies with a forward-looking view” now curious about their benefits.

And, he adds, while investment remains a hurdle for the nascent sector, some companies are willing to explore the designs and demonstrate whether the technology works in practice, among them Svitzer of Denmark.