MOL's wind-assisted propulsion design for LNG carriers approved

MOL has received an AiP for its hard sail wind-assisted propulsion (WAP) system, Wind Challenger, to be installed on a membrane-type LNG carrier. The pioneering project, jointly developed by MOL and Hanwha Ocean with input from LNG membrane tank designer GTT, marks a milestone as the world’s first LNG carrier to receive such approval for a WAP system.

The Wind Challenger WAP consists of two fibre-glass reinforced plastic telescopic sails that can reach 49-m in height, which can be retracted to lower the centre of gravity and keep the ship stable when weather is rough.

Wind Challenger employs a control system that is fully automated with proprietary technology that uses sensors to detect the speed and direction of the wind, and automatically extends, reduces and rotates the sails.

The sails have a width of 15 m and have already been installed on 2022-built, 100,400-dwt coal carrier Shofu Maru.

On the maiden voyage with the Wind Challenger WAP, Shofu Maru recorded fuel consumption reductions of 5% on the Japan-Australia route and 8% on the Japan-North America West Coast route, with up to 17% per day fuel consumption reduction when the sails were operated in automatic control mode, according to data collected from the ship.

Green Winds, a 63,896-dwt Ultramax bulk carrier which is part of the MOL Drybulk Ltd fleet, was fitted with an electric hoisting version of the Wind Challenger WAP in July 2024.

Seven newbuilding bulk carriers and multi-purpose vessels operated by MOL Drybulk Ltd are to be fitted with Wind Challenger WAPS. MOL plans to launch 25 vessels equipped with the Wind Challenger by 2030 and 80 vessels by 2035.

The issuance of the AiP underscores the vessel’s compliance with rigorous safety and design standards and the review process, based on existing regulations and ship classification rules, ensures the Wind Challenger WAP meets all necessary requirements.

This approval confirms the project vessel adheres to international conventions, providing a technical basis for the design status and preventing a rework of regulatory aspects in later stages.

ClassNK, the classification society that issued the AiP, has published comprehensive guidelines to address the risks associated with wind-assisted propulsion systems.