It may seem counterintuitive, but NVIDIA’s newest AI servers are cooled with liquid that reaches 45‑degree Celsius (113°F), hotter than a typical hot tub. By eliminating chillers and using outdoor dry coolers, the system rejects heat efficiently while keeping chips within safe limits.

Raising the chiller temperature by just one degree can cut cooling energy use by about 4 %. For a 50‑megawatt facility this translates to roughly $4 million in annual savings. Water consumption drops dramatically—from about 2.6 million gallons per megawatt per year in conventional towers to nearly zero with the closed‑loop design.

The Rubin generation of AI infrastructure uses a fully liquid‑cooled, closed‑loop loop with no fans, no cold aisles, and no evaporative towers. Coolant enters the processor at 45 °C, picks up heat and exits around 55 °C, allowing outdoor dry coolers to work most of the year. This also makes data centers quieter and more space‑efficient, shrinking a six‑rack‑unit server to just two units.

Geography still matters—desert sites need different considerations than mountain locations—but the approach reduces energy, water, noise and land‑use impacts, pointing toward a more sustainable future for data center design.