Hitachi, Mitsui O.S.K. Lines (MOL), and Japan Airlines (JAL) have launched a landmark collaboration to conduct Japan’s first pilot test of Direct Ocean Capture (DOC) technology — an emerging solution that directly extracts and captures carbon dioxide dissolved in seawater.
The pilot project will take place on Kume Island, Okinawa Prefecture, where the three companies will test the feasibility of DOC using local seawater and collect critical data on operational performance, environmental impacts and future deployment along Japan’s coastline.
The trial will use containerized pilot equipment installed on land, drawing in seawater and separating dissolved CO2. Kume Island was selected as the testing site due to its growing reputation as a hub for ocean innovation, including advanced initiatives such as Ocean Thermal Energy Conversion (OTEC). With established expertise, research capabilities and talent focused on ocean technologies, the island provides an ideal environment for Japan’s first DOC demonstration.
The companies aim to use the knowledge gained from the pilot to explore broader applications of DOC technology, including local utilization of captured CO2, environmental education programs and initiatives designed to create new value from the ocean economy — known as the Blue Economy.
Industries such as shipping and aviation face significant challenges in reducing emissions because full electrification remains difficult. As companies pursue emissions reductions, carbon removal technologies are emerging as a critical tool for addressing unavoidable emissions.
Growing demand for carbon removal has accelerated efforts to develop technologies capable of directly extracting CO2 from the environment. Building a domestic carbon removal ecosystem is also becoming increasingly important as companies seek to reduce reliance on overseas carbon credits and manage future costs.
Hitachi, MOL and JAL have each invested in Captura Corp., a U.S.-based developer of DOC technology, through their respective investment arms and other channels. By combining their expertise, the three companies have been working toward bringing Captura’s technology to Japan.
The Kume Island pilot project marks a first step toward creating an island-based, self-sufficient carbon economy where captured CO2 could eventually be used as a raw material for synthetic fuels, including E-SAF.
DOC removes CO2 directly from seawater. Oceans naturally absorb carbon until they reach equilibrium with atmospheric CO2 levels. By artificially extracting dissolved CO2 from seawater, DOC disrupts that balance, encouraging the ocean to absorb additional CO2 from the atmosphere.
Because seawater contains CO2 concentrations approximately 100 to 150 times higher than the atmosphere, DOC is viewed as a promising carbon removal technology with potential advantages in cost and energy efficiency.
Hitachi will lead the project by applying advanced measurement, analysis and artificial intelligence technologies to improve DOC efficiency. Using analytical instruments and characterization methods from Hitachi High-Tech Corporation, the company will monitor operational conditions and seawater quality data, including Dissolved Inorganic Carbon (DIC) and pH levels.
By analyzing captured data and applying Physical AI to optimize plant operations, Hitachi aims to identify conditions that maximize energy efficiency. The company will also verify CO2 capture volumes and electricity consumption data to support the development of reliable Measurement, Reporting and Verification (MRV) systems for carbon credits.
Hitachi Industrial Products, Ltd. will study the development and supply of key equipment needed for future commercial-scale facilities, with the wider Hitachi Group aiming to establish a Japan-originated intelligent DOC model.
MOL will leverage its role as an ocean-based social infrastructure company and its environmental strategy under the group management plan “BLUE ACTION 2035.”
Through its comprehensive partnership with Kumejima Town, Okinawa Prefecture, MOL will work with local stakeholders to prepare the pilot environment and explore opportunities to expand DOC adoption while creating new businesses and regional initiatives on Kume Island.
JAL will advance DOC awareness and explore future applications through its Green Transformation (GX) strategy under the “JAL Group Management Vision 2035.” The airline will also evaluate the potential use of captured CO2 as a feedstock for future production of E-SAF, supporting aviation’s transition toward lower-carbon fuels.
The three companies say the initiative represents a major step toward combining ocean technology, carbon removal and regional innovation to build a sustainable carbon cycle in Japan.
