Direct-to-chip, Two-Phase Cooling Performance Metrics and PFAS Sustainability

Richard Bonner, CTO - Accelsius Accelsius has developed a direct-to-chip, two-phase cooling solution for data centers and edge computing applications. Accelsius is formally launching an in-rack coolant distribution platform in April 2024 capable of dissipating 80kW of heat in a single rack using R1233zd(E) as the refrigerant. In this presentation we will reveal the performance of a full rack filled with high-power dual processor servers, dissipating 80kW of heat in total. We will also show results from single high-power processors, operating at powers above 2kW. The two-phase cooling product performance and capabilities will be compared to other emerging liquid cooling technologies, including immersion and direct-to-chip water (or single-phase). The presentation will also cover key data center related sustainability issues, including energy, water, and an in-depth look at PFAS concerns. According to The Green Grid's TCO model, Accelsius’ direct-to-chip two-phase cooling technology will have energy savings of 49% compared to air. The improved thermal resistance will also result in substantial water savings especially in cases where free cooling or dry-cooling is enabled by the improvement in thermal performance. The R-1233zd(E) refrigerant used in Accelsius’ product has a GWP of 1 and degrades into naturally occurring substances in the matter of a few days. This will be our first public technical presentations of the full rack testing results of our direct-to-chip, two-phase cooling system, following our product launch at Data Center World (a week before the OCP regional summit), allowing the opportunity for highly technical audiences to delve deeper. This will also be the first time we present the information found in our PFAS article exploring the continuum of “forever” chemicals, that was published in Data Center Frontier in February 2024. It should be noted that the PFAS discussion is broadly related to all cooling solutions that may use PFAS based refrigerant and dielectrics, including immersion, vapor compression, etc.