Liquid cooling

Definition

Liquid cooling is a cooling technology that transfers heat away from equipment using a liquid coolant rather than air. The coolant absorbs heat from the source and transports it to a heat exchanger, radiator, or external cooling system where the heat is dissipated.

Liquid cooling is commonly used in high-density applications where traditional air cooling may be insufficient to maintain safe operating temperatures.

Context

As power densities continue to increase across industries such as data centers, battery energy storage systems (BESS), industrial automation, and telecommunications, thermal management requirements have become more demanding.

While air-based cooling solutions remain suitable for many applications, some environments generate more heat than can be efficiently removed through airflow alone, increasing the overall thermal load placed on the cooling system. In these cases, liquid cooling offers a more effective method of transporting thermal energy away from critical equipment.

The technology is increasingly used in applications where reliability, energy efficiency, and precise temperature control are essential.

Technical insight

The primary advantage of liquid cooling lies in the thermal properties of liquids. Compared to air, liquids can absorb and transport significantly larger amounts of heat within a smaller volume.

A typical liquid cooling system consists of:

• Coolant circulation loop
• Pumping system
• Cold plates or liquid-cooled components
• Heat exchanger or radiator
• Monitoring and control systems

The cooling process generally follows four steps:

1. Heat is generated by the equipment.
2. The coolant absorbs the heat through direct or indirect contact.
3. The heated coolant is transported away from the source.
4. The heat is released through a heat exchanger before the coolant recirculates.

Because liquid cooling transfers heat more efficiently than air, it can improve overall cooling system efficiency and support higher equipment densities while maintaining stable operating temperatures.

Liquid cooling systems may be implemented as:

Direct-to-chip cooling

Coolant is circulated through cold plates mounted directly on heat-generating components.

Common applications include:

• High-performance computing
• Data centers
• AI infrastructure

Liquid-to-air cooling

The coolant removes heat from equipment before transferring it to ambient air through a heat exchanger.

Common applications include:

• Outdoor electronics
• Telecom infrastructure
• Industrial control systems

Liquid-to-liquid cooling

Heat is transferred from one liquid circuit to another, allowing integration with facility cooling infrastructure or centralized cooling systems.

Common applications include:

• Large-scale energy storage
• Industrial facilities
• High-density computing environments

Key advantages

• High cooling capacity for heat-dense equipment
• Improved temperature stability
• Reduced dependence on high airflow volumes
• Support for higher equipment density
• Potentially lower energy consumption compared to some air-based systems
• Reduced risk of localized hotspots

Applications

Liquid cooling is commonly used in:

Battery energy storage systems (BESS)

Battery systems generate significant heat during charging and discharging cycles. Liquid cooling helps maintain safe operating temperatures and improve battery performance.

Data centers and AI infrastructure

High-performance servers and AI workloads often require cooling solutions beyond the capabilities of conventional air cooling.

Telecom infrastructure

Remote and high-density telecom installations may use liquid cooling where thermal loads exceed practical air-cooling limits.

Industrial automation

Industrial systems operating in harsh environments can benefit from precise temperature control and improved cooling efficiency.

Power electronics

Converters, rectifiers, inverters, and other power equipment frequently use liquid cooling to manage high thermal loads.

FAQ