STT GDC opens South Korea's first 30MW data centre

STT Seoul 1 pips Empyrion Digital's 29.4MW from last June.

STT GDC has just opened the first data centre in South Korea to offer up to 30MW. A rival came within a whisker of that a year ago.

The new facility is developed and operated through a joint venture between STT GDC, which holds 60%, and Hyosung Heavy Industries, which holds the remaining 40%.

STT Seoul 1

STT Seoul 1 comprises approximately 40,000 sqm of gross floor area and supports up to 30MW of IT load. The facility began full commercial operations in June 2026.

Here's what we know about it. It is designed to support hyperscale and enterprise workloads, with room for evolving high-density workloads as they emerge. It has achieved LEED Gold certification, and carries a design PUE of below 1.3.

Built for resilience

One thing that caught my eye about this data centre was its focus on resilience, which starts with dual 22.9kV power feeds. That on its own is not unusual.

What stands out is that STT GDC also says the data centre has achieved Uptime Tier III Data Center Tier Certification (TCDD), which certifies actual operational performance and availability through audits rather than design intent alone. In other words, it is performance-based.

STT Seoul 1 comes with a distributed redundant UPS system and backup generators capable of running for up to 24 hours without refuelling. This is a power architecture where multiple UPS units are spread across separate power paths, so that no single UPS becomes a single point of failure. It is often described as N+N.

Finally, there is thermal energy storage (TES) for stable and continuous cooling. This gives the facility an additional buffer should the cooling systems go down.

Why South Korea

South Korea is a large and fast-growing data centre market. That said, it faces real constraints in terms of power availability, grid pressure, and high build costs.

According to STT GDC, the new data centre reflects its broader strategy of expanding into markets where digital demand, infrastructure readiness, and customer requirements are converging.

Interestingly, Empyrion Digital opened a data centre in June last year that comes in at 29.4MW of IT power, a whisker short of 30MW. Of course, we all know it is unlikely that either STT GDC or Empyrion Digital will use up its full allocation of power. But I imagine it is a talking point for STT GDC all the same.