The global shipping industry is currently experiencing a tough time due to the sluggish market situation and the oversupply of tonnage. Also, more stringent regulations on exhaust emissions have generated a significant impact on the already delicate market. Leadership in costs is one of the classic strategies to succeed in a competitive environment. Fuel is one of the most important items in the budget to consider when moving cargo across the oceans. However, up to now, there are just a few ships equipped with wind-assisted technologies to reduce fuel expenditures. Positioned in an interdisciplinary framework, this study aims to increase knowledge and understanding about the utilisation of Flettner rotors and parafoil as alternative sources of power to propel merchant vessels. To achieve this purpose, this research draws on data, information, techniques and theories from a variety of sources in both public domain and private databases. The TERA simulation of a parafoil system and Flettner rotors system assisting a 60,000 DWT bulker carrier under different wind patterns was presented. Based on the existing knowledge and scholarship, and the primary data gathered by interviews and questionnaire survey, this paper intends to critically examine the economic benefits derived from the use of two alternative propulsion systems.