Will liquid cooling be the only choice in the AI era
With the popularity of ChatGPT, a wave of AIGC has been sparked, and many domestic and foreign manufacturers have announced the launch of the Big Prophecy model. The popularity of the AIGC industry has greatly driven the demand for computing power. According to predictions, the demand for computing power will grow rapidly in the future, and global intelligent computing power is expected to reach 105ZFLOPS (1021 floating-point calculations per second) by 2030, an increase of 500 times compared to 2020.
With the continuous improvement of computing power, it is necessary to greatly improve chip performance to support it, which brings another major challenge, which is the thermal design power (TDP) of chips. At present, the power consumption of the CPU has reached 350-500W, and the power of high-end GPUs and switch ASIC chips has reached over 700W. When the chip power is further increased to over 700W in the future, the cooling design of the chip will become a serious problem.
At present, the most widely used method for chip thermal solution is air cooling, which means that a heat sink with good thermal conductivity is attached to a chip with higher heat generation, and a small fan is fixed above the heat sink. The heat on the heat sink is carried away by the airflow generated by the high-speed rotation of the fan. With the continuous increase of chip power, the effect of using traditional heat sinks for heat dissipation is no longer significant after exceeding 300W. Liquid cooling technology is considered an ideal cooling solution in the AI era.
Liquid cooling technology can be divided into three types based on its different heat dissipation methods: cold plate liquid cooling, immersion liquid cooling, and spray liquid cooling. Cold plate liquid cooling is an indirect contact type of liquid cooling that fixes the cold plate on the heat dissipation object, and the liquid flows inside the cold plate to transfer heat away from the equipment, achieving heat dissipation. Spray liquid cooling is a liquid cooling technology that sprays coolant onto the surface of IT equipment for heat dissipation, but its heat dissipation efficiency is relatively low. Immersion liquid cooling is a direct contact type of liquid cooling that completely immerses IT equipment such as servers that require heat dissipation in the coolant, and cools them through liquid circulation or phase change.
Immersion liquid cooling is considered the most mainstream and capable liquid cooling technology for large-scale deployment in liquid cooling data centers. It has the following advantages: firstly, high heat dissipation efficiency, because immersion liquid cooling directly immerses IT equipment in the coolant, which can fully contact the heat source and greatly improve heat dissipation efficiency; Secondly, the noise reduction effect is good, as IT equipment is completely immersed in coolant, which can reduce the noise emitted by IT equipment; The third is energy conservation and environmental protection. Immersion liquid cooling does not require the use of a large number of fans, which can reduce electricity consumption and carbon dioxide emissions. According to relevant data estimates, liquid cooling can save 20% -30% of the electricity required for the entire server operation compared to air cooling.
Immersion liquid cooling technology will inevitably become the mainstream cooling technology in the AI era in the future. However, the current liquid cooling technology and products are still in the initial application stage, but with the development of applications such as AI and data centers, the application and popularization of liquid cooling technology will be accelerated. According to research institutions, the market size of liquid cooled IDC in China is expected to exceed 120 billion yuan by 2025, with a growth rate of over 30%, and the proportion of submerged liquid cooling technology is expected to exceed 40%. With the further development of immersion liquid cooling technology, it may become the only choice for data center cooling in the future.
