The data centres of the future will be liquid cooled. Here's why
The simple explanation why we need liquid cooling.
Why is everyone suddenly talking about liquid cooling? Because it's the future of data centres and AI.
If you've paid attention to recent data centre announcements, or comments by data centre leaders, you would have noticed growing support for liquid cooling.
Liquid cooling
Here are some examples:
- ST Engineering's Data Centre @ Boon Lay will support liquid and immersion cooling.
- The upcoming data centre in Johor being built by TM and Singtel Nxera will support liquid cooling.
- PDG's Varoon Raghavan talked about liquid cooling changing how colocation providers operate.
At the limits of air-cooling
The reason why liquid cooling is seeing increasing traction is simple: We are at the limits of air cooling.
- Server fans already blasting at 10,000rpm or faster.
- Scores of fans crammed into every chassis.
- GPU chips reaching 1,000W and higher.
Modern data centres are generating much more heat, but gains from more fans are tapering off.
Guess what - liquid has 4x the heat capacity of air for the same mass. And liquid mass a lot more.
The AI data centre
To be clear, practically every data centre uses liquid at some level, usually by piping chilled water from centralised chillers to "air handling units" to cool the air in data halls.
Liquid cooling goes further, and can be divided into 3 main categories:
- Rear door coolers - Chiller water to each rack.
- Direct to chip (DTC) - Chilled water to CPUs and/or GPUs.
- Immersion cooling - Immersion in a liquid (not water).
There are plenty of challenges of course.
- Can be difficult to scale.
- More costly to implement in general.
- Older data centres might require retrofitting*.
* Why older data centres are often quiet about liquid cooling.
The future is liquid
But things are changing.
- OEMs such as Supermicro are selling ready-made DTC and rear door cooler solutions. Elon Musk's xAI is deploying a lot of them for instance.
- Nvidia uses an Asus-designed DTC technology with integrated liquid channels for its pricey new GB200 NVL72 supercomputer (Hint: It's US$3M per rack).
- Singapore-based SMC offers a GPU cloud service that uses its custom immersion cooling tech to halve energy consumption.
Where do you see liquid cooling going in the data centre?
