TL;DR: Nautilus cooling systems aren’t limited to seawater, they’re water-source agnostic. Our EcoCore CDUs work with natural water, municipal or industrial supply, chillers, dry coolers, and even heat recovery systems, adapting to site-specific constraints like water availability, regulations, and climate. If it can move heat, we can work with it, delivering flexible, AI-ready cooling up to 4MW per unit in any environment.
One of the most common misconceptions we hear?
“Nautilus only works in ocean-based or natural water deployments.”
Spoiler alert: It doesn’t.
Nautilus EcoCore infrastructure and CDUs are designed to be water-source agnostic. That means we can support a wide variety of site conditions, water types, and cooling strategies – whether you’re pulling from a river, tapping a municipal supply, traditional cooling tower, or running a fully closed-loop system in a dense urban zone. Let’s get into looking at the different cooling configurations and heat-rejection options we support.
The Primary Cooling Configurations We Support
Our CDUs operate at the intersection of two water delivery systems:
– Technology Cooling System(TCS): Inside the data hall, removing heat from the IT load.
– Facility Water System (FWS): Connects the CDU to the facility’s heat-rejection source.
Nautilus CDUs support the broadest range of facility heat-rejection options, including:
1. Natural Water Sources (Seawater, River, Lake)
When available, gravity-fed or pass-through natural water sources set the gold standard for cooling efficiency. These open-loop systems draw in and filter water, use it briefly for heat exchange, and then safely return it to its source only slightly warmer. Nautilus has successfully deployed this approach in California while being fully compliant with the California Environmental Quality Act (CEQA). This approach has virtually zero water consumption and low energy consumption, particularly when using gravity fed water sources.
2. Municipal or Industrial Water Supply with Evaporative Cooling Towers
Another open-loop system used in urban or industrial settings where direct access to lakes, rivers, or oceans isn’t feasible, tapping into a municipal or industrial water supply offers a practical and flexible alternative. The water needs to be filtered and carefully controlled before use, ensuring consistent quality and predictable operation. While effective, this approach consumes water and may compete with community needs, so availability and sustainability must be considered in project planning.
3. Chiller Systems
Chillers provide precise temperature control by removing heat from the facility water loop and rejecting it either to the air (air-cooled chillers) or to a secondary water loop connected to a cooling tower or other heat-rejection source (water-cooled chillers). They are highly adaptable to a wide range of climates and building types, making them a popular choice for data centers without direct access to large natural or municipal water sources. While chillers offer predictable performance year-round, they consume more energy compared to direct water-to-water systems and have higher capital and maintenance costs.
4. Dry Coolers
Dry coolers reject heat directly to the ambient air without evaporating water, using fans to move air across finned coils carrying the process fluid. They operate as a closed-loop system, eliminating the need for continuous water consumption and minimizing water treatment requirements. While they offer excellent water savings and simpler maintenance, performance can be limited in hot climates, often requiring larger equipment footprints or hybridization with evaporative assist during peak conditions.
5. Heat Recovery
Heat recovery systems capture heat from the facility water loop and deliver it to nearby buildings, industrial processes, or district heating networks. This approach turns a byproduct into a resource, reducing environmental impact and potentially creating new revenue streams or ESG (Environmental, Social, and Governance) benefits. While highly sustainable and efficient, the feasibility of this method depends on having a consistent local demand for heat and compatible infrastructure, which may not be available in all locations.
Why This Matters
You may not always have access to clean, abundant water. The truth is every site is different. Whether you’re constrained by local water policy, energy targets, space limitations, or regulatory compliance, Nautilus gives you flexible options that adapt to your deployment – not the other way around.
This flexibility is made possible by our EcoCore CDUs, which:
– Work with saltwater, freshwater, glycol mixes, and graywater
– Support open and closed loop FWS designs
– Feature integrated degassers, leak prevention systems, and multiple filtration options
– Scale up to 4000kW per unit for AI-ready infrastructure
Bottom Line: “If it can move heat, we can work with it.”
Whether you’re planning a retrofit, a greenfield site, or something in between, our team can help you design a cooling approach that works with your local water conditions, not against them.
Let’s talk early. The right cooling strategy starts with understanding your water options.
