Engineering a Cool Revolution: Shumate’s HDAC Design Tackles AI-Era Density

As artificial intelligence surges across the digital infrastructure landscape, its impacts are increasingly physical. Higher densities, hotter chips, and exponentially rising energy demands are pressuring data center operators to rethink the fundamentals, and especially cooling.

That’s where Shumate Engineering steps in, with a patent-pending system called Hybrid Dry Adiabatic Cooling (HDAC) that reimagines how chilled water loops are deployed in high-density environments.

In this episode of The Data Center Frontier Show, Shumate founder Daren Shumate and Director of Mission Critical Services Stephen Spinazzola detailed the journey behind HDAC, from conceptual spark to real-world validation, and laid out why this system could become a cornerstone for sustainable AI infrastructure.

“Shumate Engineering is really my project to design the kind of firm I always wanted to work for: where engineers take responsibility early and are empowered to innovate,” said Shumate. “HDAC was born from that mindset.”

Two Temperatures, One Loop: Rethinking the Cooling Stack

The challenge HDAC aims to solve is deceptively simple: how do you cool legacy air-cooled equipment and next-gen liquid-cooled racks, simultaneously and efficiently?

Shumate’s answer is a closed-loop system with two distinct temperature taps:

• 68°F water for traditional air-cooled systems.
• 90°F water for direct-to-chip liquid cooling.

Both flows draw from a single loop fed by a hybrid adiabatic cooler, a dry cooler with “trim” evaporative functionality when conditions demand it. During cooler months or off-peak hours, the system economizes fully; during warmer conditions, it modulates to maintain optimal output.

“This isn’t magic; it’s just applying known products in a smarter sequence,” said Spinazzola. “One loop, two outputs, no waste.”

The system is fully modular, relies on conventional chillers and pumps, and is compatible with heat exchangers for immersion or CDU-style deployment. And according to Spinazzola, “we can make 90°F water just about anywhere” as long as the local wet bulb temperature stays below 83°F, a threshold met in most of North America.