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International News
Image by Nature by approximately 15 %, while water consumption could see an even greater drop of 30-50 % throughout the data centres ' entire lifespans. This water consumption figure encompasses not only water used directly for cooling but also water utilised in power generation and the manufacturing of the various components. It is important to note that these findings are sensitive to specific design choices and may vary based on the assumptions made during the analysis.
Recognising the rarity and complexity of obtaining such detailed data, Microsoft said it is committed to transparency and collaboration. The company is making its comprehensive methodology accessible to the wider industry through an open research repository. Furthermore, the researchers shared preliminary findings at the Open Compute Project( OCP) Global Summit, a platform where the industry collaborates on hardware designs and best practices to address the ever-increasing demand for compute infrastructure. This work builds upon Microsoft’ s ongoing efforts to establish unified lifecycle assessment methods and tools specifically tailored for cloud providers.
The Nature paper marks a significant milestone as the first detailed guide on constructing a comprehensive lifecycle assessment for cooling within cloud operations, encompassing software, chips, servers, buildings and the energy grid. It also introduces a novel methodology designed to facilitate meaningful, apples-to-apples comparisons of environmental impact across different cooling solutions. By making the open research repository available, Microsoft empowers any entity within the industry to input their own specific data and scenarios to conduct a customised lifecycle assessment of their unique operations.
According to Alissa, the goal is not to dictate a single‘ right’ cooling technology. " Our intention is not to say this is the right technology. They all could be. There are different circumstances that make you use a technology,” he emphasised.“ What we’ re trying to do here is tell the industry,‘ Here’ s how you build an end-to-end lifecycle assessment that takes cooling into account. And here is a tool for you that you can customise to your specific needs and then make a decision’.”
Microsoft quantifies environmental impacts of data centre cooling.
The published study focused on cooling general-purpose compute chips( CPUs) and did not include the specialised chips designed for artificial intelligence( AI) workloads. However, the research team is currently working on a follow-up study to examine the lifecycle impacts of AI chips and anticipates observing similar benefits with the adoption of advanced cooling methods.
The study also underscored the significant influence of external factors, particularly the local energy grid. The Nature paper quantified the potential savings in energy, water and greenhouse gas emissions that could be achieved by transitioning from a typical energy grid to 100 % renewable energy sources. The findings indicated that greenhouse gas emissions could be drastically reduced by 85-90 %, irrespective of the specific cooling technologies employed. Microsoft has set an ambitious goal to power its operations with 100 % renewable energy, and in regions where fully renewable energy is not directly available through the local grid, the company procures a comparable amount of renewable energy from elsewhere.
The research team studied four distinct cooling technologies for the assessment:
• Traditional air cooling
• Cold plates( direct-to-chip liquid cooling)
• One-phase immersion( servers submerged in a circulating cooling fluid)
• Two-phase immersion( servers submerged in a fluid that boils at low temperatures for cooling)
While air cooling has been a long-standing industry standard for data centre cooling, there has been increasing interest in liquid-based cooling technologies due to their superior heat dissipation capabilities. Cold plates involve pumping a coolant through a flat container directly attached to the chips within a server rack. Onephase immersion circulates a cooling fluid through a tank containing the servers, while two-phase immersion utilises a specialised fluid that boils at low temperatures within the server tank, with the vapour condensing to provide cooling and then returning to the tank.
The study ' s findings revealed that cold plates and the two immersion cooling technologies offer significant advantages over air cooling across their entire lifecycles. These advanced methods demonstrated reductions of 15-21 % in greenhouse gas emissions, 15-20 % in energy demand, and a substantial 31-52 % in water consumption within data centres.
While the team anticipated the superior performance of liquid cooling methods compared to air cooling in terms of carbon emissions, water usage and energy consumption, this study provided the first comprehensive quantification of these benefits across the entire lifecycle of these technologies.
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RACA Journal I July 2025 www. refrigerationandaircon. co. za