Rendered image of the container-type pilot test facility and the pilot test site
Hitachi, Ltd., Mitsui O.S.K. Lines, Ltd., and Japan Airlines Co., Ltd. (JAL) have signed a Memorandum of Understanding (MOU) to conduct Japan’s first pilot test on Kume Island, Okinawa Prefecture, utilizing Direct Ocean Capture (DOC), a technology that directly separates and captures CO2 dissolved in seawater.
In a joint announcement, the three companies said the pilot test aims to confirm the applicability of DOC technology using seawater from around Kume Island, and obtain foundational data on operational challenges and environmental impacts for deployment along Japan’s coast. Specifically, the test will use containerized pilot equipment installed on land on Kume Island, taking in seawater to separate CO2.
In addition to this initiative, Kume Island hosts cutting-edge pilot projects that leverage its location, such as Ocean Thermal Energy Conversion (OTEC). With a concentration of expertise and talent in ocean research, the island offers an optimal environment for conducting Japan’s first DOC pilot test.
Based on the knowledge gained from this project, the three companies will explore potential applications and expansion of DOC technology—including local utilization of captured CO2, as well as promotional and environmental education initiatives centered on this pilot test—to contribute to the creation of new ocean-based value (the Blue Economy).
In “hard-to-abate” sectors such as shipping and aviation, where electrification alone is difficult and emissions are hard to reduce, offsetting emissions has become a key challenge alongside corporate reduction efforts.
As demand continues to grow, expectations are rising for CO2 removal technologies as a key means to address this, driving the need to establish technologies that directly remove CO2 through engineered approaches. Establishing a domestic ecosystem is also becoming increasingly important from the perspective of curbing the future cost of procuring carbon credits from overseas.
Rendered image of the container-type pilot test facility and the pilot test site
With that, the three companies have invested in Captura Corp., a U.S.-based DOC technology developer, through their respective investment subsidiaries and other channels, and have been jointly exploring a domestic pilot test toward the deployment of Captura’s technology in Japan by combining the expertise of each company.
The companies position this pilot test as a first step toward building an island-based, domestically self-sufficient carbon economy in which the recovered CO2 is ultimately utilized as a feedstock for synthetic fuels such as E-SAF.
DOC technology
DOC is a method for directly removing CO2 from seawater. Seawater naturally absorbs carbon until it reaches equilibrium with CO2 concentrations in the atmosphere. Artificially extracting and removing CO2 from seawater disrupts this balance, prompting the ocean to absorb more CO2 from the atmosphere to make up for the deficit. By repeating this cycle, atmospheric CO2 concentrations can be effectively lowered via the ocean. The concentration of CO2 in seawater is approximately 100 to 150 times higher than in the atmosphere. DOC is widely expected to be a promising climate change solution capable of capturing CO2 at lower costs and with lower energy consumption.
Under its management plan, “Inspire 2027,” the Hitachi Group has established its sustainability strategy, PLEDGES, and is leading this initiative. Utilizing advanced analytical instruments and characterization methods from Hitachi High-Tech Corporation, Hitachi will measure and record operating status and water quality/environmental data (e.g., Dissolved Inorganic Carbon (DIC) and pH in seawater). By analyzing this data and implementing Physical AI that directly feeds insights back into actual plant operations, Hitachi aims to identify and control operating conditions that deliver high energy efficiency. Furthermore, by recording and verifying data on the amount of CO2 captured and the electricity consumed, it will contribute to building an MRV(Note 7) data platform for generating highly trustworthy carbon credits. Hitachi Industrial Products, Ltd. will advance studies toward proposing and supplying the core equipment required for commercial plants. Through One Hitachi, the Hitachi Group aims to establish an intelligent DOC model originating in Japan.
Meanwhile, the MOL Group positions its environmental strategy as a key initiative under its group management plan “BLUE ACTION 2035,” advancing decarbonization initiatives as an ocean-based social infrastructure company. In this pilot test, MOL will leverage the local foundation established through a comprehensive partnership agreement(Note 8) with Kumejima Town, Okinawa Prefecture, to build cooperative relationships with local stakeholders and prepare the pilot environment. Based on the insights gained, MOL aims to contribute both to expanding the use of DOC technology and to creating new local businesses and regional initiatives on Kume Island.
As part of its Green Transformation (GX) strategy under the “JAL Group Management Vision 2035,” the JAL Group has identified carbon dioxide removal (CDR) technologies as a key initiative. In this pilot test, together with Japan Transocean Air Co., Ltd. and Ryukyu Air Commuter Co., Ltd., both of which operate flights to Kumejima, the JAL Group will leverage regional partnerships to lead promotional activities and raise awareness of DOC technology both within and outside the industry.
