Data Centers Use 560 Billion Litres of Water a Year — Five Ways to Cut Consumption

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It’s no secret that the data centers that form the hidden engine of today’s AI boom can consume huge amounts of water, mostly for cooling purposes, and dealing with this issue is critical for any organisation in the technology sector.

Worldwide, the International Energy Agency (IEA) estimates that the data center sector consumes 560 billion liters of water per year today, and projections suggest this figure could soar over the coming years, reaching as much as 1,2 trillion liters per year by 2030, according to a recent government report on data center water use.

Taking measures today can help to mitigate this.

It’s very possible for data centers to reduce the drain on local freshwater resources, while also curbing their energy use, and all without reducing performance.

Here are five key issues which are driving water consumption in data centers today, and steps that data center operators can take to mitigate them.

1 Open-loop evaporative cooling is a problem

Today, many data centers still rely on ‘open-loop’ evaporative cooling systems, where hot water is sprayed onto pads to be cooled. This older form of cooling architecture means that data centers consume significant volumes of water, which has to be continuously replenished as it evaporates.

But more modern sealed liquid cooling systems offer a way to mitigate this source of water loss, by ensuring water is reused efficiently, while not impacting performance.

Today’s closed-loop systems reuse the same water over and over again, using liquid-to-air heat exchangers for cooling, rather than evaporating water. These warm-water cooling systems are sealed, so that after the system is filled in the first place, water loss is extremely low under normal operating conditions.

Instead, the systems recirculate the same water inside a sealed environment, so no water is consumed at all during normal operations. Water is not discharged from the system, and it never evaporates: instead, it absorbs heat directly from high-performance components and transfers it out of the system.

Closed-loop systems are designed not to be consumption-driven infrastructure but instead are recirculating, self-contained systems. This technology will be vital to reducing the water demands of data centers worldwide.

2 Data centers still attempt to cool the room

In too many data centers, cooling is highly inefficient, meaning that up to a third of the data center's total energy use can be 'spent' on keeping components cool, with fans working to keep the data center's temperature low as well as cooling individual machines. Modern technologies such as direct-to-node and direct-to-chip cooling are offering a new way to curb this inefficient energy and water use.

In direct-to-chip cooling, cold plates are attached to heat-generating components such as GPUS, with coolant liquid flowing through the plates to absorb heat and transfer it out to a heat exchanger. Liquid cooling techniques such as direct-to-node cooling can remove up to 98% of heat from servers , operating on a closed-loop system which means water is not wasted.

By capturing heat directly at the source, at the processor level, rather than attempting to cool entire rooms full of hot air, data center operators can reduce energy demand and also place less strain on local water systems. This also produces higher-temperature outputs which are easier to reuse.

3 Generative AI is driving an increase in compute density

One key reason for the increasing water use of data centers is simply that the AI boom is driving more demand for cooling. Generative AI is powered by Graphics Processing Units (GPUs), which can consume between five and 10 times more energy than Central Processing Units (CPUs). But we are also seeing an increase in compute density, as more and more of these components are packed into smaller areas, using techniques such as 3D silicon stacking.

The demands of AI workloads mean that warm water closed-loop cooling is coming into its own as a low-energy solution. Even at high rack densities, warm water systems (which can use inputs at much higher temperatures) enable high performance while also curbing water use and removing evaporative cooling.

To take one example, DreamWorks Animation adopted warm-water cooling systems for high performance computing (HPC) and recorded a 20% performance increase alongside reduced cooling requirements.

4 Projects to reuse data center heat are still too rare

In data centers, almost all of the electricity used is ultimately converted into heat, and today that is a resource that is underused. In fact, the heat has been traditionally treated as an unwelcome byproduct to be removed and then discarded. But this can be transformed into a usable resource, which can deliver heat for residential communities, commercial buildings and even district heating.

This reuse is still too rare, but pioneering projects across Europe are already showing the potential of the idea for reducing reliance on fossil fuels, cutting energy costs, and boosting resilience. Projects in Ireland and Scandinavia are already reusing heat to warm homes and businesses.

Older evaporative cooling systems are wasteful, and shifting towards closed-loop systems where water is reused, heat harvested and given to the wider community are a prime example of how waste can be turned into wealth.

5 Data centers are still in the wrong locations

At present, too little thought is given to the location of data centers, meaning that the facilities can be located in areas where there is already strain on local freshwater supplies.

Going forward, organizations will take this factor into account in order to deliver more sustainable data centers which ‘fit in’ to their local environment: research found that 45% of IT professionals believe current data center design does not support sustainability goals.

In the future, data centers will be put in carefully chosen locations to optimize renewable energy use, and also to ensure their water demands are not at odds with their local environment. This could include data centers built into urban areas with a goal to reusing waste heat to warm local homes - or even to offer spa-like experiences to local people.

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