Mitsui and Hitachi Explore Feasibility of Large-Scale Floating Data Centers on Used Vessels

Mitsui and Hitachi Forge Alliance to Study Floating Data Center Venture

March 30, 2026

In a novel approach to addressing the global data center capacity crunch, Japanese industrial giants Mitsui & Co. and Hitachi, Ltd. have announced a joint study into deploying large-scale data centers on converted, second-hand ships. The memorandum of understanding, signed today, marks a significant step towards a potential operational launch as early as 2027, with initial focus on markets in Japan, Malaysia, and the United States.

The venture is positioned as a strategic response to the relentless demand for digital infrastructure, offering a pathway to faster deployment and potentially lower costs. The partners argue that utilizing existing vessels could drastically shorten construction timelines compared to traditional land-based builds. Furthermore, the inherent access to seawater or river water provides a readily available resource for cooling systems, a major operational expense, while avoiding the complexities and costs associated with terrestrial land acquisition.

Under the proposed framework, Mitsui's transport subsidiary, Mitsui O.S.K. Lines, would manage all maritime aspects, including vessel procurement and operations. Hitachi would be responsible for the design, integration, and service delivery of the data center facilities themselves. The companies have not specified if the "second-hand vessels" would be sourced from Mitsui's own fleet or from the broader market. This initiative builds on Mitsui O.S.K. Lines' prior experience, having previously partnered with Kinetics to explore developing a data center with a capacity between 20 to 73 megawatts on a 9,731-ton ship.

What distinguishes this proposal from earlier floating concepts is its envisioned scale. Mitsui highlights that a standard roll-on/roll-off (ro-ro) car carrier ship offers approximately 54,000 square meters of floor space. This vast area makes such a vessel nearly three times the size of the 1,858-square-meter barge used by U.S.-based Nautilus Data Technologies for its 6.5MW facility in California. Other projects, like Keppel's planned 19.2MW modular floating data center in Singapore or smaller demonstrations by companies like France's Denv-R, further illustrate the industry's growing interest in maritime solutions but on a comparatively smaller footprint.

The move by Mitsui and Hitachi underscores a broader industry trend of exploring unconventional locations for data centers, driven by land scarcity, power constraints, and cooling challenges. While concepts like Google's patented wave-powered ocean data centers or ambitions for space-based facilities remain largely theoretical, the Japanese partnership represents a pragmatic attempt to commercialize floating infrastructure at an industrial scale. If proven feasible, this model could offer a flexible, scalable alternative for rapid capacity expansion in coastal regions worldwide.

Source: datacenterdynamics