Immersion cooling

Immersion cooling submerges entire servers in a non-conductive dielectric fluid that absorbs heat directly from all components. In single-phase immersion, the fluid stays liquid and is pumped through heat exchangers; in two-phase immersion, an engineered fluid boils on hot components and condenses on coils above the bath. Immersion eliminates server fans entirely, achieves partial PUE below 1.05, tolerates extreme densities (100-250+ kW per tank), and shields hardware from dust and humidity. Adoption remains niche compared with direct-to-chip: challenges include fluid cost and weight, hardware warranty considerations, serviceability of fluid-coated equipment, and — for two-phase — regulatory pressure on PFAS-based fluids. It is most common in cryptocurrency mining, HPC, and edge deployments in harsh climates, with tank-based systems from vendors like GRC, Submer, and LiquidStack.