This paper analyses wind power as one category of technology in order to contribute to the body of knowledge that is needed to ascertain the potential for decarbonising shipping. Specifically, it combines a numerical model of a Flettner rotor with wind data from the UK Met Office’s Unified Model to assess the potential wind power contribution along a route from Tubarao (Brazil) to Grimsby (UK). Applying the results to a typical bulk carrier equipped with three Flettner rotors making a round voyage on the route suggests possible fuel savings of 16%. More generally, the replicable results will allow for a deeper and, in turn, more realistic examination of the prospects for wind power.