Free cooling (also known as economizer cooling) is a data center cooling strategy that uses outdoor ambient conditions—cool air or water—to remove heat from the facility instead of relying solely on energy-intensive mechanical refrigeration. By taking advantage of naturally available low temperatures, free cooling significantly reduces compressor runtime and overall energy consumption.
Free Cooling Approaches
- Airside Economizer (Direct): Outdoor air is filtered and brought directly into the data hall when ambient conditions are suitable, then exhausted.
- Airside Economizer (Indirect): Outdoor air cools the indoor air through a heat exchanger without mixing the two airstreams, maintaining better air quality control.
- Waterside Economizer: Cool outdoor air or water is used to chill the cooling water loop, allowing chillers to be partially or fully bypassed.
ATTOM and Free Cooling
In modern data centers, free cooling is a key enabler of high energy efficiency and lower Power Usage Effectiveness (PUE). It is especially effective in cooler climates or during cooler seasons, and is frequently combined with liquid cooling systems and modular designs to maximize year-round savings.
Attom Technology incorporates free cooling principles into its prefab modular data centers and precision cooling solutions, helping customers achieve lower energy costs and more sustainable operations while supporting high-density AI and edge deployments. Solutions such as AgileCore and WiseAir are engineered to take full advantage of free cooling opportunities, delivering PUE values as low as 1.15–1.3 depending on climate and configuration.
