Retrofitting WASP to a RoPax vessel - design, performance and uncertainties
Journal article, 2023

Wind-assisted propulsion (WASP) is one of the most promising ship propulsion alternatives that radically reduce greenhouse gas emissions and are available today. Using the example of a RoPax ferry, this study presents the performance potential of WASP systems under realistic weather conditions. Different design alternatives and system layouts are discussed. Further, uncertainties in the performance prediction ofWASP systems are analyzed. Included in the analysis are the sail forces as well as the aero- and hydrodynamic interaction effects, i.e., the sail–sail and sail–deck interaction as well as the drift and yaw of the ship. As a result, this study provides guidelines on the most important parameters when designing and modeling aWASP ship. Finally, the study presents an analysis of the expected accuracy of the employed empirical/analytical performance prediction model ShipCLEAN.

Flettner rotor

windassisted propulsion

ship design

energy systems model

performance prediction


Fabian Thies

Chalmers, Mechanics and Maritime Sciences (M2), Marine Technology

Jonas Ringsberg

Chalmers, Mechanics and Maritime Sciences (M2), Marine Technology


1996-1073 (ISSN)

Vol. 16 2 673

Strategic research project on Chalmers on hydro- and aerodynamics

The Chalmers University Foundation, 2019-01-01 -- 2023-12-31.

WASP - Wind assisted ship propulsion

Interreg, 2019-08-15 -- 2023-01-15.

Chalmers, 2019-08-15 -- 2023-01-15.

Driving Forces

Sustainable development

Innovation and entrepreneurship

Areas of Advance



Subject Categories

Energy Engineering

Vehicle Engineering

Energy Systems

Fluid Mechanics and Acoustics


Basic sciences



More information

Latest update