Japan Airlines announced on August 4, 2026, that it has signed an agreement with Hitachi and Mitsui O.S.K. Lines to conduct Japan's first pilot test of Direct Ocean Capture technology on Kume Island in Okinawa Prefecture. The joint project aims to extract carbon dioxide directly dissolved in seawater to support atmospheric decarbonization efforts.
Under the trial plan, the companies will install land-based containerized equipment on Kume Island to draw in local seawater, strip out dissolved carbon dioxide, and release the processed water back into the ocean. The pilot is designed to evaluate the technology's performance under real-world ocean conditions while gathering practical operational and environmental data to guide potential future deployments along Japan's coastline.
All three companies have previously invested in Captura Corp., a United States-based ocean carbon capture technology developer, and have spent time exploring options to deploy the technology in Japan. Within the project framework, Hitachi will oversee technical monitoring using analytical tools to track water quality and operational metrics, while developing a data platform to verify captured carbon for potential carbon credit trading.
Mitsui O.S.K. Lines will leverage its existing relationship with the local government on Kume Island to coordinate with residents and construct the pilot site. Meanwhile, Japan Airlines, working alongside regional partner carriers Japan Transocean Air and Ryukyu Air Commuter that currently operate flights to Kumejima, will lead community outreach and public awareness efforts for the project.
Kume Island was selected as the pilot location in part because it already hosts ocean-based energy research infrastructure, including a system that generates electricity from ocean temperature differences. Because seawater holds roughly 100 to 150 times more concentrated carbon dioxide than atmospheric air, ocean capture is viewed as a potentially less energy-intensive and lower-cost approach to emissions offset. Over the long term, Japan Airlines plans to explore utilizing the captured carbon dioxide as a raw material to produce sustainable aviation fuel.
