Nvidia's Vera Rubin is in production, and it's reshaping how we think about data center cooling. The headline spec that matters for mechanical engineers and facility designers: 45°C inlet water temperature, 100% liquid cooled, no chillers required.

Jensen Huang said it plainly at CES: "With 45 degrees C, no water chillers are necessary. We are cooling this supercomputer with hot water."

That's a real inflection point. Chillers have been the dominant cost and energy burden in data center thermal management for decades. Eliminating them is a massive win. But what replaces them?

“Only fans” is not a cooling strategy

The industry's knee-jerk reaction has been predictable: if you don't need chillers, just use dry coolers. Fans pushing ambient air across a heat exchanger. Simple. Cheap. Done.

We think that's a dangerous oversimplification, and the most ambitious data center programs will figure that out quickly.

Here's the problem. Dry coolers need a temperature gap between the process fluid and the ambient air to work. The industry calls this the "approach" or delta T. Most facilities spec their dry coolers for about a 5°C approach. That means if your process fluid returns at 45°C, your dry coolers stop being effective when the ambient hits 40°C.

And 40°C ambient days are not rare. Phoenix, Dallas, Saudi Arabia, India — these are exactly the markets where AI infrastructure is scaling fastest. On those days, your dry coolers are stranded assets. Your Vera Rubin racks are throttling or shutting down. You've built a facility that can't run at full capacity on the hottest days of the year.

When things get hot, get SkyCool

SkyCool panels reject heat by convection, AND by radiating it directly to the cold sink of outer space. The panels incorporate a special ultra reflective, ultra radiative film that remains colder than the air at any ambient temperature.

This isn't marginal. On a 42°C day, dry coolers are fighting thermodynamics. SkyCool is still radiating to a 3-kelvin sky. 

The economics follow the physics. At high process fluid temperatures — exactly where Vera Rubin operates — SkyCool's cost per kW of rejected heat drops. The hotter the fluid, the more aggressively our panels radiate. 

At 45°C process temps, SkyCool panel arrays are cheaper than dry coolers per ton of cooling. And that’s before you account for the massive energy savings.

Energy, Noise, and Resilience

Dry coolers spin big fans. Fans consume power, and they consume more of it as ambient temperatures rise — exactly when your facility is already strained. SkyCool uses a fraction of that energy at any temperature. There are almost no moving parts. The energy profile is flat and predictable.

Then there's noise. Data center operators increasingly face noise ordinances and community pushback. Dry cooler farms are loud. SkyCool panels are silent.

And there's a subtle but important difference in how these systems interact with their environment. Dry coolers blow hot air out of the building and into the surrounding area. They make the local microclimate hotter, which in dense deployments can create feedback loops that degrade the performance of neighboring equipment. SkyCool radiates heat to space. The air around the facility stays cooler. On a campus with multiple buildings, that distinction compounds.

Finally, resilience. SkyCool panels are solid-state infrastructure. No fans to fail. No compressors to maintain. Designed to operate for decades with minimal servicing. For facilities planning 20- to 30-year operational lifetimes, that maintenance profile matters.

The Real Question for Facility Designers

The question isn't whether you can cool Vera Rubin without chillers. You can. Nvidia solved that.

The question is whether you're going to build a facility that works only when the weather cooperates — or one that delivers full capacity every hour of every day, quietly, efficiently, and for decades.

Fans are fine for mild climates and moderate ambitions. If you're building the most capable, most resilient AI infrastructure in the world, SkyCool is how you close the gap.