Japan’s Mitsui OSK Lines (MOL) has received approval in principle (AiP) from classification society ClassNK for an LNG carrier featuring two hard sails.

The telescoping hard sail Wind Challenger has been developed by MOL in partnership with the University of Tokyo and Oshima Shipbuilding.

According to MOL, this is the world’s first approval for an LNG carrier with a wind-assisted propulsion system.

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The AiP was issued for the 174,000 cu metre LNG carrier equipped with two Wind Challenger sails and can enter LNG terminals worldwide.

Following the approval, the detailed design work is underway for a new LNG carrier ordered by MOL at Hanwha Ocean shipyard, aiming for the actual installation.

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MOL, Hanwha Ocean, and ClassNK evaluated the placement of the sails, their impact on visibility, emergency operation procedures, and other safety measures before awarding the AiP.

The assessment of the impact on the cargo tank due to the sail installation, conducted by French company GTT, the designer of the vessel’s cargo tank, contributed to obtaining this AiP. GTT has confirmed that the structural safety of the tank is sufficiently ensured, even when considering the stresses imposed by sails, MOL said.

The Japanese shipping company plans to launch 25 vessels equipped with the Wind Challenger by 2030 and 80 vessels by 2035 to meet its net zero GHG emissions by 2050.