On the morning of the 5th, the Digital Realty Data Center 'ICN10' located in Sangam-dong, Mapo-gu, Seoul. ICN10 is a place that lends data center infrastructure to clients who wish to implement artificial intelligence (AI) and cloud services. Inside, dozens of IT devices, standing over 2 meters high, were in operation. These devices, called 'racks', gather servers (large computers) needed for AI and cloud services and supply them with power. About 1,500 racks are in operation within ICN10.
Digital Realty, based in the United States, is the world's largest data center specialist company providing customized data center services. Digital Realty currently operates over 300 data centers in 25 countries worldwide. Currently, 5,000 corporations around the world are utilizing Digital Realty's data centers. Customers who have entered Digital Realty's data centers can request custom rack production or simply use existing racks for lending, among various other services.
The total area of data center-related facilities from the first to sixth floors of Digital Realty ICN10, completed in 2022, is 4,500 pyeong (15,109 square meters). This is about twice the size of the nearby Seoul World Cup Stadium. The power capacity of ICN is 12 megawatts (MW), and the industry typically considers facilities ranging from 5 to 100 MW as medium-sized data centers capable of conducting AI model training.
ICN10 has dozens of global major corporations as clients, including AWS Korea and KakaoBank, as well as major domestic and international telecommunications companies. On this day, employees were busily bringing in racks for newly entered clients into the building. So Hyun-jae, a manager at Digital Realty, noted, "Having a data center in the metropolitan area makes it easier for personnel to manage, which is preferred by clients," and explained, "Sangam-dong in Mapo-gu is a representative area of data center concentration, and due to government tax benefits, we decided to make it the first data center location in the country."
Digital Realty is focusing on attracting clients by emphasizing the power efficiency of ICN10. Digital Realty supplies power to the internal servers of the racks through four independent pathways. Compared to operating the racks with a single source, this method allows for efficient power distribution according to need, reducing expenses. Digital Realty's Power Usage Effectiveness (PUE) is 1.2, meaning the closer the number is to 1, the more efficient the power usage. Typically, data centers multiply the PUE by power consumption to charge clients, with the industry average known to be around 1.5 to 2.0.
Digital Realty chose to dualize the cooling system for the stability of ICN10. It employs both air-cooling (cooling with air) and water-cooling (cooling with water) methods, which are predominantly used by most data centers. By utilizing both methods, they can cool the heat generated by the racks according to the situation. Kim Yong-ji, an engineer at Digital Realty, said, "In the case of next-generation GPUs used for AI implementation, the temperature can soar to 40 degrees as soon as they are activated," and emphasized, "Having a cooling system suited to the conditions is essential for improving data center stability."
A separate auxiliary power source has also been established to enhance system stability. On the second floor of ICN10, an 'ATS switch' that transitions to an emergency generator when there are disruptions in power supply and a 'UPS system' that prevents server damage are in place. When switching to an emergency generator, diesel fuel powers the operating engine. These systems are isolated from the area where the racks are located to ensure safety even in the event of a fire. Security has been strengthened by installing CCTV that operates 24 hours a day at the building entrance, allowing only individuals with an access card to enter.
Digital Realty aims to open the second data center in Gimpo City, Korea. The Gimpo data center is planned to be built five times larger than ICN10. Manager So Hyun-jae said, "The Gimpo data center is planned to be built larger than before to provide services specialized for AI training to clients," adding, "As Korea is a market where AI transformation is rapidly taking place, we hope to respond proactively."