AI 경쟁에 따라 늘어난 고전력 GPU 서버 냉방이 중요 이슈로 떠오른 가운데, SKT가 획기적인 냉각방식 검증에 성공해 업계에 관심을 모으고 있다.
Air cooling compared to cooling power 93%, server power 10% ↓
Verification from last June, applied to Incheon Data Center next year
As cooling of high-power GPU servers has emerged as a key issue due to the AI competition, SKT has successfully verified a groundbreaking cooling method, drawing attention from the industry.
SKT announced on the 14th that it had successfully verified 'liquid immersion cooling' technology, a next-generation thermal management method that cools various servers by immersing them in special non-conductive cooling oil.
GPU servers consume dozens of times more power than general servers (x86), and GPU server operation, cooling/humidification, and cooling consume close to 40% of data center electricity usage. Domestic and international data centers are actively working to reduce power consumption by introducing low-power, high-efficiency cooling technologies or by installing efficient cooling systems that use next-generation energy.
According to the International Energy Agency (IEA), the estimated global data center power consumption in 2022 is 240-340 TWh, which is a huge amount equivalent to 42-60% of the country's annual power consumption.
SKT has been building an immersion cooling system in its Incheon office building using equipment from GRC, a US immersion cooling specialist, test servers from various manufacturers, and SK Enmove’s special cooling oil (Thermal Fluids, ZIC-GC2), and has been testing it for four months since June. As a result, it announced that it has confirmed the effect of reducing total power by 37%, with cooling power reduced by 93% and server power reduced by more than 10% compared to existing air cooling.
The liquid immersion cooling system is an oil-cooling system that cools the server by directly immersing it in a special cooling oil that does not conduct electricity and has high thermal conductivity, unlike the existing air-cooling system that circulates cold air or cools through a fan.
By using a special cooling oil with much higher thermal conductivity than air, the heat from the server equipment is directly absorbed, and by eliminating the server fan required for air cooling, not only cooling but also power saving of the server is possible. SKT also explained that it is expected to extend the lifespan of servers as they are free from humidity, dust, and noise, which are the main causes of server failures, and that it can stably maintain the temperature of the entire system, including not only the CPU and GPU, which are heat-generating elements inside the server, but also the memory and storage devices, thereby reducing the cause of equipment failure due to high temperatures.
In fact, SKT conducted performance tests on each server and found that there was no difference in performance, and compared to the same performance test results, immersion cooling confirmed that server power was reduced, improving power-to-weight ratio.
SKT plans to build a dedicated data center for its AI services in its Incheon office building in November and plans to fully implement the liquid immersion cooling system next year.
SKT said, “As the heat generation of GPU server systems continues to increase, data center energy consumption is rapidly increasing, and big tech companies such as Google, MS, and Intel are also considering introducing liquid immersion cooling.”
For example, Equinix, Digital Reality (Hungary), etc. are pushing for the introduction of liquid immersion cooling systems as Intel's recent CPU design changes to connect multiple chiplets to create larger chips, which also increases power consumption.
SK Enmove invested $25 million in GRC last year and signed a business agreement with GRC and Dell Technologies to develop technology to expand demand for data center immersion cooling systems and establish an after-sales service (AS) market. He also participated in SKT's immersion cooling demonstration and review, contributing to the successful results.
SKT plans to combine this solution with SK Enmove's thermal management business to launch a full-scale immersion cooling business, and expects to lead the spread of immersion cooling technology in the future to contribute to achieving net-zero through power reduction in data centers.
SKT CIO (Chief Information Officer) and Vice President Cho Dong-hwan said, “As we accelerate our transition into an AI Company, the introduction of high-power consumption GPU servers is increasing. We expect to save significant energy costs through the introduction of this immersion cooling system, and we will contribute to achieving our carbon neutrality goal by expanding the use of this technology in the future.”