The city of Ulsan is launching a full-scale effort to build a "carbon-zero underwater data center" that uses seawater as coolant, in partnership with the Korea Institute of Ocean Science and Technology (KIOST).
Ulsan announced Wednesday that it has been selected as the final site for the "Carbon-Zero Underwater Data Center Standard Model Development Project" led by the Ministry of Oceans and Fisheries, securing 40 billion won ($29 million) in central government funding over the next five years. A total of 51.1 billion won, including the government funds, will be invested through 2030 to address surging power consumption and heat generation at data centers driven by the expansion of artificial intelligence and big data industries.
The project centers on a seawater cooling system that leverages Ulsan's offshore waters, which maintain an annual average temperature of 13.3°C. To overcome the massive cooling power consumption and site acquisition challenges facing conventional onshore data centers, the project will combine pressure vessel design technology with ultra-high-efficiency hybrid cooling technology. The goal is to verify operational performance at a power usage effectiveness (PUE) level of 1.2 at a depth of 20 meters.
Servers and power distribution equipment will also be developed in modular, standardized configurations to ensure both cost-effectiveness and scalability for future large-scale complex construction. To drive the project forward, Ulsan signed cooperation agreements in January with 12 industry, academic and research organizations including KIOST, the Ulsan National Institute of Science and Technology (UNIST), POSCO, GS Engineering & Construction and SK Telecom.
Starting this year with optimal site analysis and basic design, Ulsan plans to complete performance testing facility installation and demonstration by 2030. From 2031, the city will begin constructing a large-scale commercial underwater data center complex.
"Through this joint public-private-academic-research project combining ocean science technology and information and communications technology, we will overcome the limitations of onshore data centers," an Ulsan city official said. "We will expand our maritime digital territory with the underwater data center as a base and elevate Ulsan into a sustainable AI capital."