The data center industry is juggling the exploding compute demands from AI/ML and HPC workloads with a sustainability crisis. As racks climb beyond 30kW and regulators in the EU, U.S., and APAC demand usage of renewable energy, promote net-zero operations, and demand better and better PUE, traditional cooling has become the single point of failure. Air-cooled systems (CRACs) waste facility energy battling physics alone—a staggering 40% of total energy in air-cooled facilities is consumed solely to cool electronics while struggling to cool racks beyond 15-20kW.
It isn’t just inefficient, it’s a crisis in the making.
The good news is that Cooling Distribution Units (CDUs) have evolved from niche solutions to the backbone of sustainable high-density computing. Unlike air cooling methods, or costly piecemeal infrastructure hardware, modern CDUs solve the dual challenge of scaling AI while slashing environmental impact.
Benefits of CDUs vs. traditional data center infrastructure
Cooling Distribution Units (CDUs) help to solve the data center sustainability crisis through three fundamental breakthroughs:
- Liquid efficiency
Liquid-powered CDUs bypass air’s limitations by delivering water cooling or coolant directly to the heat source via rear-door heat exchangers, direct-to-chip systems, or otherwise. Rack-scale precision means data centers can deploy custom water distribution to eliminate oversubscribed cooling—AKA every GPU gets exact thermal management. This enables 3,000x greater heat transfer efficiency than air cooling, easily managing AI-enabled 100kW+ racks, something unobtainable for CRAC units. Critically, this precision eliminates “overcooling” waste—where traditional systems chill entire rooms to protect a few hotspots.
- Prefabricated velocity
Legacy cooling retrofits and new builds gamble with 18-24 month timelines due to custom configuration needs and infrastructural overhauls. In comparison CDUs arrive as factory-tested “data center products” that deploy in <12 weeks (vs. 12-24 months for traditional builds) while slashing capital risk. For example, Nautilus EcoCore COOL’s standardized skids integrate pumps, controls, and heat exchangers in a single footprint. Some CDU providers even offer customization options for specific space restrictions while still meeting faster timelines.
The modularity also allows for phased scaling, so a data center only needs to start with the number of CDUs they need to meet current requirements with the ability to expand when growth is hot. This “pay-as-you-grow” approach prevents costly overprovisioning and aligns with hyperscaler procurement strategies.
On top of phased scaling, prefabricated CDUs also impact upfront CapEx—Nautilus EcoCore COOL CDUs eliminate the need for CRAHs and CRACs, reducing material, spatial, and operational costs to enhance overall efficiency and accelerate deployment.
- Retrofit-ready
Unlike immersion cooling requiring rip-and-replace, CDUs can integrate diverse cooling methods (liquid, rear-door, direct-to-chip, immersion) within the same hall. They are ideal for replacing legacy hardware so CDUs like Nautilus EcoCore COOL allow organizations to update to high-density racks without as much risk or CapEx.
For example, CDUs can quickly adapt without the same level of drastic overhauls to power, plumbing, floor weight capacity and more. Their compact, standardized form factor avoids structural reinforcements—critical when retrofitting older facilities not designed for 6,000-lb racks and simplifies permitting in constrained markets like Singapore or Tokyo. Dual-pump N+1 redundancy ensures uptime during critical transitions
Nautilus EcoCore COOL powers sustainable AI data centers
While CDUs as a whole solve part of the equation, Nautilus EcoCore COOL redefines data hall-scale efficiency. The Start Campus in Portugal is just one example of how it delivers where others compromise—they deployed 12 EcoCore COOL CDUs in just 12 weeks. The results rewrote the playbook:
- 12MW cooling capacity across dual 3.4MW loops
- Liquid-to-air cooling via rear-door heat exchangers
- Zero wasted energy with targeted cooling flow to >50kW racks
- Zero water risk with a closed-loop system immune to drought restrictions
This wasn’t a lab experiment—it was a live deployment proving CDUs can outpace AI’s growth while beating sustainability targets. The system’s dual-loop design allows simultaneous cooling of high-density AI racks and traditional servers—futureproofing for hybrid environments
Depending on the choice of cooling system, Nautilus EcoCore Infrastructure can support up to 30% lower OpEx by eliminating air-handling energy waste and cutting water usage to near-zero levels—saving ~380M gallons annually in a 100MW facility.
Are CDUs necessary for long-term data center sustainability?
The short answer? Absolutely.
CDUs are the only long-term solution to the data center sustainability crisis. If facilities need to:
- Slash PUE to ≤1.1 to meet EU EED/CSRD mandates requiring public reporting by 2025
- Support 100kW+ racks demanded by next-gen Blackwell/Hopper GPUs without thermal throttling
- Prevent grid strain by reducing cooling-related power draw by 40-50% in stressed markets like Virginia
- Power tomorrow’s AI without drowning in water restrictions or facing carbon taxes
…then CDUs are the proven path forward. As AI density doubles every 2 years, traditional cooling becomes a dead end. CDUs turn sustainability compliance into competitive advantage—delivering scalable precision cooling that converts waste heat into community energy under EU heat-reuse mandates.
