AWS Ulsan (SK Group) data center, Nam-gu, Ulsan

SK Group and Amazon Web Services are building an AI data center in the Mipo National Industrial Complex in Ulsan, on South Korea's southeastern coast north of Busan, on a site formerly operated by SK Chemicals. SK Telecom and SK Ecoplant broke ground on August 29, 2025, and the facility is to reach 103MW at completion, with 41MW available by November 2027 and the whole facility by February 2029. The project is set to house 60,000 GPUs, and Korea's Ministry of Science said it would bring 7 trillion won ($5.11bn) of investment to the region.

SK Gas will supply liquefied natural gas to SK Multi Utility, whose combined heat and power plant will provide the electricity, and SK Ecoplant is leading the design and construction. The GPU racks are designed to draw 20 to 40 kilowatts each, cooled by a hybrid air and water system. SK Telecom and SK Broadband bought the roughly 36,000 square meters of land from SK Chemicals for 28.3 billion won, according to Construction Review Online.

"This project is not just about putting up a building, but about laying the foundation of Korea's digital economy and building its future," SK Supex Council Chair Chey Chang-won said at the groundbreaking. Ulsan's city government expects the project to create jobs and spread AI uses such as digital twins and smart factories in local manufacturing, and Ulsan Mayor Kim Doo-gyeom attended the ceremony.

The plan has since grown: SK Telecom has said it will expand the Ulsan site to gigawatt scale as part of a push for up to 15 gigawatts of AI data centers, with 5 gigawatts to come online in stages from 2029. In September 2026, SK Group Chairman Chey Tae-won said at the Ulsan Forum that the site was nearing 900 megawatts of planned capacity and that talks with global technology companies were moving quickly. "I am worried if we make huge investments, but there is not much return," Chey said at the same forum. In August 2026, SK Telecom moved its data center assets, including the Ulsan project, into a new company, SK Horizon, in which KKR and an IMM-led consortium agreed to invest 3.08 trillion won.

The next milestone is the first 41MW phase, due in November 2027.