Quantifying voyage optimisation with wind propulsion for short-term CO2 mitigation in shipping

Abstract

The global shipping sector requires deep and rapid carbon reductions within a decade to align with Paris Agreement goals. Wind propulsion offers a retrofit option where sails provide renewable power to reduce emissions from a ship's engine. Combining wind propulsion with voyage optimisation shows synergistic potential, but the underlying technical mechanisms at play are poorly understood. Here, we model wind propulsion on globally distributed routes to show how voyage optimisation amplifies carbon saving to over 30% on ideal routes as ships exploit a critical dependency on wind speed and angle. Reduced shipping speeds further increase savings, and all technologies combine to reduce carbon by up to 60%, demonstrating the potential for substantial CO2 cuts from existing technologies. The findings challenge the sector to urgently broaden its narrow focus on alternative fuels by providing a steer on how to cut shipping's committed emissions and bring shipping closer to Paris Agreement goals.