IN-24-034 - Green Refrigerant-Based Compact Hybrid System for Ultra-Efficient and Sustainable HPCs Cooling PDF

Data centers, constituting approximately 2% of total U.S. electricity consumption and experiencing rapid growth, urgently require energy-efficient strategies. The cooling infrastructure, responsible for up to 40% of a data center's energy consumption, emerges as a critical area for improvement. Addressing this need, our paper introduces a pioneering cooling approach—the Hybrid Direct-to-Chip (D2C) Pumped Two-Phase and Single-Phase Immersion System. This system is meticulously designed to harness the strengths of two distinct cooling technologies. The innovative system seamlessly integrates the superior thermal performance of D2C pumped two-phase technology, specifically tailored for high-power components like CPUs and GPUs. Simultaneously, single-phase immersion cooling systems, while facing thermal constraints, prove optimal for discrete, low-power sources. The hybrid system targets the elimination of energy-intensive air cooling, yielding substantial energy savings, potentially achieving PUE < 1.05. Additionally, it aims to maximize operational efficiency by allowing operation in extreme climatic conditions without the need for chillers—an essential feature in reducing overall energy consumption. To ensure sustainability, our system replaces R134a with a green refrigerant replacement boasting a GWP < 1. In summary, the proposed Hybrid D2C Pumped Two-Phase and Single-Phase Immersion Cooling System not only presents a comprehensive solution to the challenges of individual cooling technologies but also serves as an innovative approach that improves thermal performance, enhances energy efficiency, and contributes to the sustainability and effectiveness of server cooling system