[Report] Visiting the Construction Site of Korea's First SK AI Data Center, the "AI Heart" on a Site the Size of 11 Soccer Fields

Power Density and Cooling Capacity 10 Times Higher Than Standard Data Centers
Specialized Mechanical, Electrical, and Plumbing (MEP) Solutions as the Foundation
Synergy Expected from Using LNG Terminal Refrigerant for Heat Management

On the morning of October 29, foundation piling work was in full swing at the construction site of the "SK Artificial Intelligence (AI) Data Center (DC) Ulsan," where piles are driven deep below ground to support the building's load. This site is being developed by SK in partnership with Amazon Web Services (AWS), the world's leading cloud company, as a hyperscale AI data center that will house 60,000 graphics processing units (GPUs). The total site area is approximately 66,000 square meters (20,000 pyeong), equivalent to the size of 11 soccer fields. Construction began in August, and the foundation work is now in full progress. Lee Dongkyu, the site manager at SK Ecoplant, stated, "Our goal is to launch services by the end of the fourth quarter of 2027," adding, "From December onward, the construction site will change rapidly with each passing day."

On the 29th, the foundation work was underway at the SK AI Data Center Ulsan site, currently under construction by SK Ecoplant. SK

SK Group selected SK Ecoplant as the contractor for the AI DC and invested a total project cost of about 7 trillion won. The group aims to increase the power density at this site by up to ten times compared to standard data centers and to boost cooling capacity for heat dissipation by more than tenfold. Lee emphasized, "The construction is focused on ensuring that the AI DC, which consists of high-heat, high-power equipment, can deliver top performance stably." He added, "Specialized mechanical, electrical, and plumbing (MEP) solutions are the foundation. To ensure continuous and stable operation, we are implementing uninterrupted power supply as well as heat source and air conditioning equipment, and we have also secured backup routes for power and chilled water supply in case of emergencies."

One of the key challenges for the AI DC is managing server heat generation. AI servers produce significant heat, requiring an environment where a constant temperature can be maintained at all times. The SK AI DC plans to implement a "hybrid cooling system" that combines air and liquid cooling to efficiently cool the high-density racks where servers and IT equipment are concentrated. This method merges the advantages of air cooling, which uses cold air to dissipate heat, and liquid cooling, which directly supplies coolant to semiconductor chips or central processing units (CPUs) to remove heat. Kim Jaeseok, Head of AI DC Technology at SK Broadband, said, "Stable power supply and cooling are the most crucial functions of an AI DC," and added, "A major advantage is the ability to flexibly combine cooling methods to meet customer demand."

Korea Energy Terminal liquefied natural gas (LNG) tank currently in commercial operation. SK

About a 15-minute drive from the AI DC, three liquefied natural gas (LNG) storage tanks, each three times the size of Jangchung Gymnasium in Seoul (diameter 90.6 meters, height 54.7 meters), come into view. This is the Korea Energy Terminal (KET), Ulsan's first LNG terminal, jointly built by SK Gas and Korea National Oil Corporation. In the future, this facility will be responsible for supplying power to the SK AI DC Ulsan.

KET is considering utilizing the low-temperature energy of LNG as a cooling source for the data center, instead of releasing it into the sea, once the AI DC Ulsan is completed. Currently, 10,000 tons of seawater per hour are used to vaporize LNG. If it proves economically viable, a refrigerant will absorb LNG's cold energy instead of seawater, transfer it to the data center to cool the servers, and then return-now heated-to KET to assist in LNG vaporization. A KET official explained, "If refrigerant is used instead of seawater, it will reduce the environmental impact by using less seawater and also help the data center save on electricity costs."