China Liquid Cooling Server Penetration Rises from Under 3% in 2021 to 20% in 2025

Liquid cooling data centers have become a focal point for the AI industry. The evolution of data center cooling from air cooling to cold plate liquid cooling and then to full liquid cooling architecture is becoming increasingly clear, driven by the surge in computing density under the AI wave.

China's liquid cooling server penetration rose from under 3% in 2021 to 20% in 2025. Global AI data center liquid cooling penetration increased from 14% in 2024 to 33% in 2025. Cold plate liquid cooling dominates, while immersion liquid cooling currently holds a small share and is only suitable for specific scenarios such as supercomputing and high-density AI training. At the 2026 World AI Conference, supernode systems from leading server vendors including Huawei, ZTE, H3C, and Inspur have been fully upgraded to liquid cooling. The Ascend 950 supernode, designed for trillion-parameter large model training, emphasizes liquid cooling configuration, while the ZTE OEX supernode achieves full cold plate liquid cooling coverage.

Coolant is a key medium in liquid cooling systems. Industry standards such as the "Technical Requirements for Cold Plate Liquid Cooling Data Centers" have been released, but much standardization work remains for coolants. Coolants including PG 25, EG 25, and deionized water have not yet been unified. The standard composition of PG 25 is 25% propylene glycol and 75% deionized water, with each vendor adding small amounts of proprietary additives, and the formulas are not publicly disclosed. Both PG 25 and EG 25 have antifreeze properties; pure water freezes at 0°C, posing a risk of freezing for outdoor pipes in winter, which PG 25 can effectively avoid. Deionized water has limited application scenarios, while PG 25 is more suitable for long-chain large data center deployments. There is no unified industry standard for the coolant replacement cycle.

The operational complexity and construction cost of liquid cooling are real challenges. Newly built data centers generally adopt an air-liquid hybrid architecture, with the share of air cooling continuing to decline. From the IT equipment side, liquid cooling penetration continues to rise.