Anemoi Marine Technologies completed a joint development project to simplify integrating Rotor Sail wind propulsion on medium-range (MR) tankers, and classification society DNV granted Approval in Principle (AiP) for the design.
The work targets how owners can install wind-assisted propulsion on product tankers where deck space, cargo handling and safety constraints often complicate deployment.
DNV’s AiP covers an MR design with two folding, explosion-rated Rotor Sails
The project integrates two folding, explosion-rated Rotor Sails into an MR tanker design, using Anemoi’s 5 by 35-meter folding Rotor Sails.
DNV reviewed the design package and issued the AiP after considering how the Rotor Sails are treated under the International Maritime Organization’s Energy Efficiency Design Index (EEDI) and Energy Efficiency Existing Ship Index (EEXI) frameworks.
Guangzhou Shipyard International and Hafnia shaped the integration package
The development was carried out in collaboration with Guangzhou Shipyard International (GSI) and tanker operator Hafnia.
The project’s stated objective was to provide a verified design basis for shipowners who want to install wind-assisted propulsion systems on product tankers.
Deck-seat design aims to avoid underdeck strengthening and keep access for maintenance
Alongside the Rotor Sail installation, the project developed a lightweight deck seat intended to avoid the need for underdeck strengthening.
That same deck-seat approach is described as allowing inspection and maintenance access.
What Anemoi’s executives say the certification changes for owners
Nick Contopoulos, Chief Production and Partnerships Officer at Anemoi, said demonstrating that Anemoi’s EX-rated Rotor Sail can be integrated efficiently, safely, and with minimal structural impact gives owners a clear, verified pathway to adoption.
The project was presented as having demonstrated potential energy-efficiency benefits while providing a pathway for wind-assisted propulsion adoption in the MR tanker sector.