Anemoi secures approval for rotor sail-ready MR tanker design

Anemoi Marine Technologies and its partners have completed a joint development project that integrates folding wind-assisted propulsion into a medium-range (MR) tanker design, providing shipowners with a verified pathway for deploying rotor sails on this vessel type.
Developed with Guangzhou Shipyard International (GSI) and tanker operator Hafnia, the concept incorporates two folding, explosion-rated rotor sails designed for installation on product tankers operating in hazardous deck environments. Classification society DNV reviewed the design and issued an Approval in Principle (AiP), covering the technical, structural, operational and regulatory aspects of the integration.
The project addressed key challenges associated with fitting wind-assisted propulsion systems on MR tankers, including limited deck space, cargo handling requirements and safety considerations. Anemoi and GSI also developed a lightweight deck foundation that avoids the need for underdeck strengthening while maintaining accessibility for inspection and maintenance.
DNV's assessment included the treatment of the rotor sails under the IMO's EEDI and EEXI efficiency frameworks, including the impact of sail interactions on vessel performance calculations. The resulting approval provides owners with a validated design basis for future installations.
Nick Contopoulos, chief Production and Partnerships officer at Anemoi, said: "Completing this project is a significant step for wind-assisted propulsion in the tanker sector. Demonstrating that our EX-rated rotor sail can be integrated efficiently, safely and with minimal structural impact on MR tankers gives owners a clear, verified pathway to adoption."
"Identifying practical, scalable efficiency measures for the MR tanker segment is a priority for Hafnia as we navigate increasing energy efficiency and emissions reduction demands from both charterers and regulators,” said Hafnia general manager technical Jesper Kristiansen. “The work undertaken with Anemoi, GSI and DNV gives us a credible technical foundation from which to assess deployment of wind-assisted propulsion across this fleet.”