Embracing alternative fuels would mean retrofitting engines – a process that might take 12-14 months, cost between $5m-$15m per ship, and is only appropriate for about 10% of vessels. This is without considering the uncertainties around the price and availability of green fuel, which is currently predicted to cost 4 to 9 times more than its fossil-based alternative. The wingsails automatically retract if the wind isn’t blowing sufficiently, to avoid creating windage, and also when conducting loading/dis