AWS Embraces Liquid Cooling to Power Next-Gen AI in Data Centers

Published Date : 12/06/2025 

AWS is transitioning from air-based to liquid-based cooling systems in its data centers to support advanced AI innovations and improve energy efficiency. 

At its simplest, a data center requires three things to function properly. The first is a building, designed to protect the servers from the elements. The second is power, the electricity that keeps the servers running. The third is cooling, which is essential to prevent servers from overheating and shutting down. Amazon Web Services (AWS) is currently transitioning from air-based to liquid-based cooling systems, a shift that is crucial for supporting the next generation of artificial intelligence (AI) and meeting evolving customer needs.

The shift matters because data centers need to evolve to stay relevant. Last year, AWS announced it would be rolling out new data center components designed to support advanced AI innovations and improve energy efficiency. The transition to liquid cooling is a key part of this adaptation.

While the term 'cooling' might evoke images of air conditioning, data center cooling is quite different. According to Dave Klusas, AWS’s senior manager of data center cooling systems, the goal isn't to maintain a comfortable temperature but to move just enough air through the servers to prevent overheating while using the least amount of energy and water. In the summer, data halls can be quite warm.

Until now, air-based systems have been sufficient for cooling AWS's data centers. These systems work by pulling air inside and circulating it through the server racks. The air absorbs heat from the electronics and is then expelled outside, allowing cool air to come in and repeat the process. However, with the advent of AI chips, air alone is no longer enough.

AI chips perform trillions of calculations per second, consuming more power and generating more heat than other types of chips. This requires more airflow to remove the heat, making air-based cooling impractical and costly. As Klusas explains, 

Frequently Asked Questions (FAQS): 

Q: What is the main advantage of liquid cooling over air cooling in data centers?

A: Liquid cooling is more efficient because liquid is over 900 times denser than air, allowing it to absorb significantly more heat. This makes it more economical and practical for cooling high-performance AI chips.

Q: Why is AWS transitioning to liquid cooling?

A: AWS is transitioning to liquid cooling to support advanced AI innovations and improve energy efficiency, as air cooling is no longer sufficient for the high heat generated by AI chips.

Q: How does AWS's liquid cooling system work?

A: AWS uses a direct-to-chip approach with a 'cold plate' placed directly on top of the chip. Liquid runs through sealed tubes in the cold plate, absorbing heat and carrying it out of the server rack to a heat rejection system.

Q: What was the development timeline for AWS's liquid cooling system?

A: It took four months to go from a whiteboard design to a prototype and 11 months to deliver the first production unit, including time for design, supply chain building, control software writing, testing, and manufacturing.

Q: How will the liquid cooling system scale up in AWS data centers?

A: The system will be ramped up this summer to handle more cooling workloads and will start moving into other data centers, with flexibility built in to adapt to changing needs. 

More Related Topics :