ClassNK approval for “hard sail” propulsion technology

Image of Wind Challenger, single-sail type. Credit: VPO

Classification society ClassNK has granted an approval in principle to the design of a hard sail system being developed by Japan’s Mitsui OSK Lines (MOL) and Oshima Shipbuilding Co. The so-called Wind Challenger Project converts wind energy into propulsive force using a telescopic hard sail.

In obtaining the classification society’s approval, the two companies officially completed the initial design phase of the sail’s structure and controls. They will now continue into the more advanced steps of design and implementation – ultimately aiming to launch a newbuild vessel outfitted with a hard sail.

According to a statement from MOL, the hard sail could reduce a vessel’s greenhouse gas emissions by 5% on a Japan-Australia voyage, and about 8% on Japan-North America west coast voyage. Eventually, Oshima and MOL expect to equip vessels with multiple sails for maximum emissions reduction.

The Wind Challenger Project received approval based on ClassNK’s ‘Guidelines for Wind-Assisted Propulsion Systems for Ships’, which were issued in September to enhance the safety of vessels using auxiliary wind propulsion.

The project was started in 2009 with the Wind Challenger Plan, an industry-academia joint research project led by the University of Tokyo. In 2013, the team was chosen to receive a “subsidy for next-generation marine environment-related technology research” by Japan’s Ministry of Land, Infrastructure, Transport, and Tourism.

Oshima Shipbuilding and MOL took control of the project’s plan in January 2018.