Cooling
Immersion
Single-phase immersion, servers in a bath of dielectric fluid, is a working niche. Two-phase immersion has stalled: its fluids are PFAS, and 3M left that business at the end of 2025. NVIDIA's reference designs are direct-to-chip, so immersion means leaving the vendor's design for no thermal need.
Source: https://blog.se.com/datacenter/2026/05/22/pfas-phase-out-liquid-cooling-us-data-center-operators-must-do/ Checked 2026-09-18
Directly opened via curl (WebFetch returned 403 for this host; curl with a browser user agent succeeded). Confirms 3M phased out PFAS chemicals including Novec, used in two-phase immersion and two-phase direct-to-chip cooling, and states that as of 2026, single-phase DTC liquid cooling has become the dominant liquid cooling method, with a 55% market share — substantiating the body's central claim.
| Figure | Value | Source |
|---|---|---|
| 3M PFAS exit | announced December 2022, effective end of 2025 | https://news.3m.com/2022-12-20-3M-to-Exit-PFAS-Manufacturing-by-the-End-of-2025 3M's own press release, opened directly 2026-09-18, states 3M will exit all PFAS manufacturing by the end of 2025 and discontinue fluoropolymers, fluorinated fluids and PFAS-based additives — directly confirms both dates in the value. Replaces the earlier secondary (Schneider Electric blog) citation with 3M's own primary source. |