by
Accelsius Marketing
The rapid expansion of global data center infrastructure—driven by AI, cloud computing, and high-performance workloads—has exposed a critical constraint: climate. Recent analysis from Rest of World reveals exactly how narrow the territory of “acceptable climates” has become for our industry—and how many data centers are built beyond this territory’s boundaries.
The optimal operating temperature range for most data centers lies between 18°C and 27°C (64.4°F to 80.6°F). And yet, of the 8,808 facilities currently in operation, approx. 7,000 (or ≈80%) are in regions where ambient conditions regularly fall outside that range. Even more notably, around 600 data centers (≈10% of the global total) are in climates that frequently exceed 27°C.
For data centers in hotter regions (such as Singapore, the UAE, and parts of India), a systemic mismatch exists between their external climate and their cooling demands. To compensate, many facilities currently rely on inefficient legacy cooling systems to fill this “climate vs. cooling” gap, worsening energy consumption and cranking up OpEx.
And while others have somewhat eased their energy strain by making the switch to liquid cooling, they’ve quickly learned a valuable lesson: not all liquid cooling is created equal. In fact, only one liquid cooling solution has proven it can widen the climate map for data centers—redefining where the industry can comfortably build next.
Liquid moves forward. Single-phase holds it back.
In the early days of liquid cooling adoption, approaches like immersion and direct-to-chip (D2C) were praised for their ability to leverage liquids’ superior heat transfer capabilities to dramatically improve efficiency. In particular, D2C cooling was highlighted for targeting the most heat-intensive components—CPUs, GPUs, and accelerators—by delivering coolant directly to the source, reducing dependence on ambient air conditions and enabling higher rack densities.
However, it’s become clear that water-based single-phase (1P) D2C systems still face limitations. Their thermal performance is constrained by relatively strict temperature operating windows, often demanding supplemental mechanical cooling to maintain efficiency—especially in warmer climates.
This “supplemental mechanical cooling” for single-phase can take the form of higher pumping power requirements to satisfy AI. Higher flow rates introduces higher risk of erosion, driving up maintenance costs for your system’s most critical components. It also surges energy costs, consuming greater fractions of annual OpEx as AI workloads demand greater cooling.
To truly break free from climate constraints, a more advanced approach is needed.
Two-phase direct-to-chip: The true path forward
Unlike single-phase systems, two-phase D2C cooling utilizes the latent heat of vaporization. As the coolant absorbs heat from the chip, it changes phase from liquid to vapor, enabling far greater heat removal at stable temperatures. This mechanism allows 2P D2C systems not only to operate at lower flow rates (4x-9x lower vs. 1P D2C), but also to operate efficiently at higher coolant temperatures.
The result is an additional 6–8°C of thermal headroom vs. single-phase, which has far-reaching implications. It means reduced energy dependence for your data center, enabling 35-44% savings in annual OpEx and 5-year TCO savings of 8-17% (according to Jacobs Engineering).
Furthermore, by raising the allowable facility water temperature, two-phase D2C effectively broadens the range of climates in which data centers can operate efficiently. Regions that were once considered too hot can now support high-density compute without incurring excessive cooling penalties.
Unlocking free cooling at scale
One of the most significant benefits of this increased thermal headroom is its impact on free cooling—the ability to reject heat using ambient conditions without energy-intensive refrigeration.
In a country like Singapore, the idea of accessing free cooling for most of the year previously sounded like science fiction. Rest of World reports that “all of Singapore’s 72 data centers are located in a climate that is too hot for optimal operation.” Therefore, any cooling system that does enable optimal operation in this hot, humid territory without recklessly straining local energy sources could—and should—be seen as a veritable gamechanger.
2P D2C can accomplish exactly that.
According to available data from ASHRAE:
- Single-phase D2C systems enable free cooling only about 24% of the year
- Meanwhile, two-phase D2C systems, with a 6–8°C higher facility water temperature, can enable free cooling up to 97% of the year.
This massive difference in free cooling frequency becomes a huge victory for cost savings and sustainability initiatives alike—all while ensuring mission critical data centers are prepared for future eras of AI.
Expanding the Data Center Frontier
Historically, data center site selection has prioritized cooler climates to minimize cooling costs. This has led to geographic concentration in regions with naturally favorable conditions. The rise of AI and latency-sensitive applications, however, has shifted this approach. Now, infrastructure is increasingly deployed closer to population centers, many of which are in climates too warm for true optimization.
NeuCool® two-phase direct-to-chip cooling is a compelling solution to overcome this climate hurdle. Its superior performance lays the foundation for a more scalable, sustainable, and geographically flexible future for data center infrastructure.