Data center cooling

Glossary cooling By Rickard Andersson

Definition

Data center cooling refers to the systems and strategies used to remove heat from servers, networking equipment, storage systems, power electronics, and other equipment within a data center environment.

Effective cooling maintains equipment within appropriate operating temperatures while managing airflow, temperature distribution, and energy consumption.

Cooling can range from conventional air-based systems to liquid cooling technologies designed for high-density computing environments. The appropriate approach depends on thermal load, equipment density, facility design, ambient conditions, and reliability requirements.

Context

IT equipment converts a significant portion of the electrical energy it consumes into heat. As computing capacity and equipment power density increase, more heat must be removed from the same physical space.

If this heat is not effectively managed, internal temperatures can rise and hotspots can develop around equipment. This can reduce equipment reliability, affect performance, and increase the risk of unplanned downtime.

The cooling challenge is particularly important in edge data centers and micro data centers. These installations often combine significant computing capacity with limited space and may operate outside the tightly controlled environments found in larger facilities.

Data center cooling must therefore be considered as part of the overall data center infrastructure, alongside power, equipment layout, environmental protection, and monitoring.

Technical insight

Data center cooling works by transferring heat from IT equipment to an environment where it can be safely dissipated.

The cooling process generally involves three stages:

Heat is generated by IT and supporting equipment.
Thermal energy is transferred away from heat-generating components.
The collected heat is rejected outside the equipment or data center environment.

How these stages are achieved depends on the cooling architecture.

Air cooling

Air cooling uses moving air to transport heat away from IT equipment.

Most conventional servers draw cooler air through the front of the equipment and discharge heated air through the rear. Cooling systems then remove heat from the surrounding air before it is recirculated or replaced.

Effective airflow management is essential because sufficient cooling capacity alone does not guarantee effective equipment cooling. Poor airflow distribution can cause heated exhaust air to recirculate and create localized hotspots.

Liquid cooling

Liquid cooling transfers heat using a circulating coolant rather than relying entirely on air.

Because liquids can transport significantly more heat within a smaller volume, liquid cooling is increasingly used for high-density computing, AI infrastructure, and other applications with concentrated thermal loads.

Approaches include direct-to-chip cooling, where cold plates remove heat directly from processors, and liquid cooling architectures that transfer collected heat to air or another liquid circuit.

Cooling capacity and thermal load

Cooling systems must be sized according to the amount of heat generated by the equipment.

The thermal load is influenced by:

IT equipment power consumption
Rack power density
Power conversion equipment
Equipment utilization
Ambient conditions
Enclosure or facility design

Insufficient cooling capacity can result in excessive temperatures, while significantly oversized cooling equipment can increase cost and reduce operating efficiency.

Temperature and airflow management

Maintaining an appropriate average room or enclosure temperature is only part of effective data center cooling.

Airflow paths and temperature distribution must also be controlled to prevent individual equipment areas from operating significantly hotter than others.

Rack layout, cable routing, equipment placement, containment, and cooling system positioning can all influence airflow and temperature gradients within the installation.

Energy efficiency

Cooling can represent a significant part of the energy required to operate data center infrastructure.

Improving cooling system efficiency can reduce electricity consumption and operating costs while maintaining the thermal conditions required by IT equipment.

Energy performance depends on several factors, including cooling technology, equipment load, ambient conditions, airflow design, control strategy, and the Energy Efficiency Ratio (EER) of mechanical cooling equipment.

Key advantages

Maintains appropriate IT equipment temperatures
Reduces the risk of localized hotspots
Supports reliable equipment operation
Enables higher equipment density
Supports continuous data center operation
Can improve overall infrastructure energy efficiency

Applications

Data center cooling is used across different types of digital infrastructure.

Data center and IT infrastructure

Modern data center and IT infrastructure relies on cooling to maintain reliable operating conditions for servers, networking equipment, storage systems, and supporting power equipment.

Edge data centers

Distributed IT infrastructure often places computing capacity closer to users and data sources. Cooling systems within edge data centers must provide reliable thermal control within compact installations and varying deployment environments.

Micro data centers

A micro data center integrates computing equipment and supporting infrastructure within a small footprint, making efficient thermal management particularly important where available cooling space is limited.

Telecom and connectivity

Modern telecom and connectivity infrastructure increasingly combines networking equipment with local computing resources, creating cooling requirements for distributed telecom and edge installations.

Industrial automation

Edge computing used within industrial automation can place servers and networking equipment in environments with elevated temperatures, dust, and other challenging operating conditions.

Defense and security

Distributed computing and communications systems used in defense and security applications can require cooling solutions designed for compact, remote, or environmentally demanding installations.

FAQ

Data center cooling is the process of removing heat generated by servers, networking equipment, storage systems, and supporting infrastructure to maintain appropriate operating temperatures.

Data centers can use air cooling, liquid cooling, or combinations of different cooling technologies. The appropriate method depends on equipment density, thermal load, facility design, ambient conditions, and performance requirements.

Edge data centers often combine significant computing capacity with limited physical space and may operate in less controlled environments. Effective cooling helps maintain reliable equipment temperatures despite these constraints.