日经特写：商船三井双硬帆LNG船在韩国巨济岛亮相，日本三大船社推进硬帆/风筝翼风力助推减排——纯技术展示，无订单金额、收入或指引增量

GEOJE, South Korea/TOKYO -- Japanese shipping companies are developing vessels that use hard sails or kites to harness ocean winds, looking to reduce fuel consumption and carbon dioxide emissions.
Mitsui O.S.K. Lines unveiled Monday a liquefied natural gas carrier equipped with two rigid sails at Geoje Island in southern South Korea. The vessel was constructed at a shipyard of South Korean shipbuilding giant Hanwha Ocean for American oil major Chevron.
"A world-first technology that uses the power of wind like the sails of a yacht has been completed," a Mitsui O.S.K. representative said.
Two sails tower on either side of the LNG carrier's bow. Mounted on the deck, each of these sails is about 15 meters wide and can extend to a maximum height of roughly 49 meters. They can also rotate 180 degrees from side to side.
Mitsui O.S.K. developed this system, which it calls Wind Challenger, with universities starting in 2009. Sensors detect wind direction and speed, automatically adjusting sail angle and height. Made from lightweight yet durable glass-fiber-reinforced plastic, the sails are designed to maximize reductions in LNG fuel consumption.
A coal carrier equipped with a single Wind Challenger sail achieved average fuel savings of 5% to 8% per voyage, according to Mitsui O.S.K. The LNG carrier unveiled Monday is the first to carry two sails, which the company expects will boost fuel savings to as much as 12%.
A second twin-sail vessel is scheduled for completion in 2026. Mitsui O.S.K. is also working with major South Korean shipbuilders to develop a four-sail version. The company now operates three Wind Challenger-equipped vessels and aims to expand the fleet to 25 by 2030 and 80 by 2035.
The International Maritime Organization has set a goal of reducing greenhouse gas emissions from shipping to net zero by around 2050. In the near term, this is expected to lead to wider adoption of vessels powered by LNG, which emits less CO2 than conventional fuel oil. Over the longer term, ammonia- and hydrogen-powered ships, which do not emit CO2 during combustion, are expected to become more common.
But next-generation fuel vessels remain costlier to operate than those running on conventional fuel oil. They also require some continued use of fuel oil to ensure stable ignition and meet safety requirements.
To advance decarbonization smoothly, the shipping industry must improve fuel efficiency alongside the shift to alternative fuels, leading to a focus on harnessing ocean winds.
NYK Line, another Japanese shipping company, installed a suction sail -- a technology that draws in and amplifies wind, using the resulting pressure difference to generate propulsion -- on a bulk carrier in 2024.
Norwegian shipping group Wallenius Wilhelmsen has begun foldable-sail demonstration testing on a car carrier. Made from steel and glass fiber and measuring 46 meters high and 14 meters wide, the company expects the sail to cut fuel consumption on windy North Atlantic routes by 7% to 10%.
Kawasaki Kisen Kaisha is betting on kites. Its paraglider-shaped Seawing system captures stronger winds at higher altitudes and converts them into propulsion. Originally developed as a venture within European aircraft builder Airbus, the business was taken over by the Japanese shipping company in 2024.
Kites require less onboard installation space than sails, making them easier to fit on a wider range of vessels, according to the company. Demonstration tests are underway using a kite with an area of about 600 square meters, expected to reduce fuel consumption by more than 10%. Kawasaki Kisen plans to introduce the system on a bulk carrier as early as 2027 and aims to equip five vessels by around 2029.
Combining multiple wind-assist technologies could generate even greater benefits. Kawasaki Kisen is also developing rotor sails -- cylindrical rotating structures mounted on deck that catch and make use of the wind. "Rather than rely on a single approach, we want to move forward by combining a variety of measures," corporate officer Kei Onishi said.