France-based classification society Bureau Veritas (BV) has delivered an Approval in Principle (AiP) to Zéphyr & Borée for its first open-top 1,800 TEU containership, demonstrating the feasibility of using wind-propelled wing-sails on this type of vessel.
The 185m container vessel is designed with five cargo holds, mostly open-top. Propulsion is compliant with IMO’s Tier III requirements, and the vessel is equipped with shaft generators and a heat recovery system that minimises fuel consumption. The vessel’s propulsion system will be assisted by eight sails provided by CWS (Computed Wing Sails). The design is a thick, asymmetrical wing-sail that can be steered to catch port and starboard winds and adjusts itself automatically depending on the wind conditions to ensure optimal savings.
BV was involved from the very early stage of the design. The main design principles were reviewed in order to ensure the feasibility of the concept and identify any obstacles. The AiP confirms the design’s compliance with the most recent BV notations, including NR 206 on Wind Propulsion systems.
Nils Joyeux, CEO at Zéphyr & Borée said, “We are convinced that the wind energy will play an important role in the years to come to decarbonise ships’ propulsion. The integration of sails on container ships is an important technical challenge on which we are working hard at Zéphyr & Borée. We are delighted to collaborate with BV on this project, which represents a key milestone by demonstrating the viability of wing-sails as a wind propulsion solution for container ships. We intend to continue our work with maritime stakeholders to offer wind propulsion solutions that are economically viable and make a tangible difference for the sector.”
Laurent Leblanc, Senior Vice President Technical & Operations at Bureau Veritas Marine & Offshore, commented, “Wind, even if it is not always available, is a serious option to help decarbonise the shipping industry. Wind propulsion systems can play a significant role by providing substantial propulsive energy. With this AiP, we are pleased to demonstrate the technology can be applied to containerships, which represent 17.5% of the global fleet (in tonnage). Bureau Veritas continues to lead the way in developing guidelines and frameworks for the safe and efficient use of this promising technology.”
To help clients move forward with wind-assisted propulsion, Bureau Veritas has released classification rules that provide a framework for wind propulsion systems (WPS). These rules address safety and reliability from the design review stage through installation and operations, including survey regimes and maintenance requirements. To comply with WPS rules, ships must undergo a risk analysis, determine local and general ship strength, and define load cases, automation and release systems.