Microsoft – cooling data centers without water?

As a leader in computer software, operating systems, cloud computing, and AI applications, Microsoft introduces groundbreaking technology aimed at reducing water usage in the ICT sector. This innovative solution seeks to decrease the environmental burden of data centers while protecting diminishing water resources in various regions. What does this innovation entail?

The problem with data centers

The rapid development of artificial intelligence and cloud platforms has increased the demand for data centers—physical “warehouses” of servers with immense capabilities. These facilities consume not only massive amounts of electricity but also significant quantities of water. The latter is primarily used to cool servers and comes from local sources, adding pressure to specific watersheds.

Until now, Microsoft’s data centers have used evaporative cooling technology, which transforms heat in the air into latent energy in the form of humidity. Simply put, water supplied to the centers evaporates, cooling the air and preventing the electronic equipment from overheating. While effective, this solution has become increasingly controversial, considering global droughts and challenges in ensuring water supply for populations.

The new cooling method – implementation plan

In August 2024, Microsoft began rolling out new data center cooling technology utilizing a closed-loop water system. The system is filled with H₂O during construction, and its operation requires no additional water resources. Cooling occurs at the chip level, allowing precise temperature control of servers. According to Microsoft, this solution will save 125 million liters of water annually per data center.

Existing data centers currently operate with both the old and new technologies simultaneously. However, the tech giant promises that starting in 2026, new centers planned in Phoenix, Arizona, and Wisconsin will be equipped exclusively with mechanical cooling systems. Water will then only be used for building administration purposes, such as kitchens and restrooms.

Microsoft’s environmental commitment

Microsoft’s new initiative is a continuation of its goals outlined in a June 2024 declaration, aimed at minimizing reliance on local natural resources and reducing the operational footprint of data centers for the benefit of local communities. These investments are already delivering measurable benefits in water management, tracked using the Water Usage Efficiency (WUE) metric. This metric represents the annual amount of water used for humidification and cooling in data centers relative to their energy demand.

In 2021, Microsoft’s global average WUE was 0.49 liters/kWh, which decreased to 0.30 liters/kWh in 2024—a 39% improvement in water efficiency. Initiatives like expanding the operational temperature range and using recycled water in Texas, Washington, California, and Singapore have contributed to this success. The new server cooling technology is expected to bring the WUE metric close to zero, according to company representatives.

Microsoft acknowledges that implementing mechanical cooling systems will increase nominal energy consumption in data centers. However, efforts are underway to develop technological enhancements to mitigate this effect. Furthermore, recognizing its role and responsibility as a leader in AI systems, Microsoft aims to further transform its data centers to achieve net negative carbon emissions and zero waste by 2030. By 2025, the company also plans to power its data centers entirely with renewable energy, expanding and decarbonizing local electrical grids.