Harnessing the Wind: The Rise of Wind-Assisted Ship Propulsion (WASP) in the Transformation of Maritime Transport

The global maritime sector, which transports over 80% of international trade, is under increasing pressure to reduce greenhouse gas (GHG) emissions, which have risen by 20% over the past decade. Among emerging decarbonisation strategies, Wind-Assisted Ship Propulsion (WASP) stands out as a promising solution that harnesses renewable wind energy, with the potential to reduce emissions by up to 100%. This paper explores the technical maturity, regulatory context, and market viability of key WASP technologies, including rotor sails, suction sails, hard wing sails, and kites. It outlines the evolving regulatory landscape, such as carbon pricing and fuel intensity standards coming into effect from 2025, which is driving increased interest in WASP. A comprehensive technical analysis of the three systems is provided, focusing on aerodynamic principles, installation requirements, and operational performance. The article concludes with an assessment of market trends, noting that as of early 2025, 52 vessels are already equipped with WASP and an additional 97 are on order. The study affirms WASP’s strategic role in enabling near-term emissions reductions and supporting the maritime industry's transition toward full decarbonisation.