Part 4 of 9

Liquid Cooling Strategy

ASHRAE Zone 6B climate, 98% free cooling hours, and water-side economization.

Target PUE

1.10-1.15

Free Cooling

98%

Technology Stack & Feasibility

Cooling Technology Comparison

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Air Cooled (Chillers)

Feasibility: Low
PUE
1.4-1.6
Max Density
15-20 kW/rack
🟡

Water Cooled (Evaporative)

Feasibility: Medium
PUE
1.2-1.3
Max Density
30-50 kW/rack
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Liquid Cooling (Direct-to-Chip/DLC)

RECOMMENDED
Feasibility: High
PUE
<1.15
Max Density
100+ kW/rack (AI Standard for NVIDIA H100/Blackwell)

Rack Density Requirements

Power per Rack (kW) - AI workloads demand 4-6x higher rack density than legacy infrastructure

CapEx Premium Analysis

Construction Cost per MW ($M)

$1.5MM/MW Premium (15-20%) for AI-Ready Infrastructure

Climate Profile: ASHRAE Zone 6B

Kalispell sits in ASHRAE Zone 6B (Cool/Dry), a dramatic contrast to San Antonio's Zone 2A. Annual Cooling Degree Days (CDD): ~147 (Base 65°F). Compare to San Antonio's ~3,187 CDD—a 95% reduction in cooling load.

Free Cooling Analysis

With water-side economizers or dry coolers, you can run compressor-free for 8,500+ hours/year—approximately 98% of annual operating hours. This eliminates mechanical cooling requirements for the vast majority of the year.

Efficiency Impact

Target PUE: 1.10-1.15, among the best achievable in North America. Using adiabatic cooling in this climate consumes significantly less water than evaporative towers in Texas due to lower wet-bulb temperatures.

Water-Side Economization

The cool/dry climate enables highly efficient water-side economizers. Heat rejection potential includes district heating integration—selling waste heat is viable in Kalispell's cold winters, unlike San Antonio.

Density Support

Direct Liquid Cooling (DLC) supports 100+ kW per rack, mandatory for modern AI architectures. DLC captures 70-80% of heat generated, with the remaining load easily handled by ambient air in this climate.

Zero-Water Option

For sites where water permitting proves difficult, air-cooled chillers paired with DLC remain highly efficient in this climate. Unlike Texas where this would push PUE to 1.35+, Montana's cool ambient temperatures keep PUE near 1.20 even without evaporative cooling.