How to Cut Data Center Cooling Costs with Efficient Strategies

Cooling: A Major Cost Driver

It’s often said that energy costs are the lifeblood of a data center’s operational budget, and cooling is one of the largest consumers of that energy. 

You’re typically spending about 25% to 40% of your total energy budget exclusively on cooling infrastructure, making it the second-largest operational expense behind powering the actual IT servers. It also depends on the size of the infrastructure and the intensity of the data being processed (such as standard cloud storage versus AI workloads and so on). 

As servers and IT equipment draw more power and generate more heat, the expense to keep them within safe temperatures grows. 

And so reducing data center cooling costs has become a strategic priority, both to improve profit margins and to meet sustainability goals. 

Fortunately, there’s now a wide range of efficiency strategies that can cut cooling expenses without compromising performance or reliability. These range from simple fixes to comprehensive architectural changes.

1. Optimize Airflow and Containment

The lowest-hanging fruit in cooling cost reduction is often boosting the efficiency of existing air cooling systems. 

Begin by scrutinizing airflow management in the facility: Are hot and cold aisles properly separated with containment (doors, panels, or curtains) to prevent hot and cold air from mixing? 

Improper air circulation makes cooling units work overtime, directly inflating costs. Cold aisle/hot aisle containment ensures that cold supply air reaches the server intakes without being diluted by hot exhaust, and that hot air returns directly to cooling units. By implementing robust containment and sealing gaps (such as using blanking panels in empty rack slots), many data centers have immediately seen better temperature control and often raise their thermostat setpoints a few degrees, saving significant energy on CRAC/CRAH operations.

Additionally, removing airflow blockages is vital. Regularly organize cabling and clear obstructions under raised floors or in rack enclosures to allow unobstructed air movement. When airflow is unimpeded and well-directed, cooling equipment can do the same job with less power. These adjustments often cost relatively little but yield measurable reductions in cooling energy consumption.

2. Raise Inlet Temperatures and Use Economization

Modern servers are designed to tolerate higher inlet air temperatures than many legacy data center operators might expect. If your data center is currently running overly chilly, you may be paying for more cooling than needed. 

After ensuring good containment and monitoring, consider gradually raising the supply air temperature setpoint within ASHRAE-recommended ranges. Even modest increases in inlet temperature setpoints can reduce cooling energy consumption when implemented within ASHRAE-recommended ranges. The key is to do this strategically: monitor server inlet temperatures and establish a comfortable margin that avoids any equipment hitting thermal thresholds.

Another proven way to reduce cooling costs is through free cooling or economization. Air-side economizers bring in cool outside air when conditions allow, bypassing mechanical cooling. Water-side economizers use cooling towers or dry coolers to reject heat when outdoor temperatures are low enough, skipping or reducing chiller operation. In the right climate, economization can deliver huge savings by tapping into cool seasonal or nighttime air. Even if full “free cooling” isn’t possible year-round, partial economization for a portion of the time still cuts down the hours that energy-intensive chillers or AC compressors must run.

3. Deploy Variable Speed and Demand-Driven Cooling

Legacy cooling infrastructure often runs at a constant output, even when the IT load is light, which wastes energy. Upgrading to variable frequency drives (VFDs) on CRAC/CRAH fans and chilled water pumps enables the system to match output to real-time demand. When server loads are lower (e.g., nights or weekends in an enterprise data center), cooling capacity can automatically throttle down, saving power. 

Additionally, modern cooling control systems offer intelligent automation that adjusts cooling in response to sensor inputs. For example, if one zone of the data center is running cooler than needed, the controls can reduce fan speeds or water flow in that area to avoid overcooling and waste. Retrofitting older equipment with VFDs and smarter controls may involve some investment, but it can often pay back quickly through energy savings.

4. Target Hot Spots with Close-Coupled Cooling

One reason cooling systems become inefficient is that one small area of high heat density forces an entire room’s cooling to run harder than necessary. By addressing those critical hot spots separately, you can ease the burden on the overall cooling system. 

In-row or in-rack cooling units are excellent tools for this. They provide close-coupled cooling right at the source of the heat, supporting high-density racks without having to overcool the whole room. 

For example, a row of racks with new GPU-intensive servers may overwhelm a room’s general cooling. Adding an in-row cooler or rear-door heat exchangers for that specific deployment can remove most of the heat locally, allowing the rest of the room’s cooling to operate normally, saving energy. 

Strategically deploying these supplemental cooling solutions for particularly dense zones can postpone or eliminate the need to drop the temperature across the board or to invest immediately in a larger facility-wide system.

5. Transition to Liquid Cooling for Greater Savings

As server densities continue to climb, even the best-optimized air cooling will eventually hit a wall of diminishing returns. That’s when shifting to direct liquid cooling can unlock a new level of efficiency and cost reduction. 

Liquid cooling – whether through direct-to-chip cold plates or other methods – carries heat much more efficiently than air, enabling “warm water cooling” that can drastically shrink or eliminate mechanical cooling needs like chillers. For facilities running at the top of their capacity, a move to liquid cooling can reduce cooling energy use by 20-30% or more, directly impacting the bottom line. This transition does require capital investment in new systems (liquid-cooled servers, CDUs, piping), but over the long term it can pay off through both energy savings and increased computing capability per watt.

A Phased Approach to Cost Efficiency

Reducing data center cooling costs typically isn’t one silver bullet, but rather a series of improvements that collectively make a big difference. 

A phased approach works well: first optimize what you have (airflow, containment, control systems), then implement targeted enhancements like economization and close-coupled cooling for hot spots, and finally consider larger architectural shifts like direct liquid cooling for the highest density environments. Each step builds on the previous, continually improving the cooling efficiency and trimming the power bill. 

Over time, these efforts not only reduce operating expenses but also create a more sustainable and scalable data center that can handle future workloads without runaway energy costs.

See how CoolIT’s direct liquid cooling products (passive coldplates, rack manifolds, Coolant Distribution Units, and rear-door heat exchangers) deliver measurable OpEx reductions, whether you’re targeting a few high-density racks or a facility-wide transition.

Talk to a CoolIT specialist about your cooling costs and build a phased plan that pays back fast.