Robert Tustin, a naval architect at classification society Lloyd’s Register who works as a project manager for newbuilding projects, typically gets to spend no more than two years on an assignment.

But in 2018, Lloyd’s Register chief executive Nick Brown assigned Tustin a project that he is still working on today, more than four years later. He has been working with a coalition of companies including Malaysian shipowner MISC Berhad and shipbuilder Samsung Heavy Industries to develop what could become one of the world’s first tankers powered by ammonia.