Data center water, cooling and power

• Water quality, not source, decides if alternative cooling water works
• AWS already uses reclaimed water at 26 data centers
• Dry cooled liquid cooling brings on-site WUE near zero
• Granada’s SP01 campus reports a design WUE of 0.0013 L/kWh
• A Karnataka micro data center runs air cooled with a PUE below 1.3
• Lugano’s ALPS supercomputer runs on local hydroelectricity and trains Apertus
• OCP sessions now treat coolant chemistry as part of the system
• Singapore now requires a PUE of 1.25 or better for new capacity
• Poland expects installed data center capacity to triple within four years
• Dassault Systèmes and Vertiv validate an AI factory in a virtual twin

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AI footprint measurement

• The Sustainable AI Group released CLEER, with Etsy as first adopter
• Agentic sessions use about 27 times the energy of a chat
• The least efficient models use over 30 times the most efficient
• Etsy targets flat cloud emissions intensity through 2027
• Wiley’s ARI uses about 88% less generative AI energy than an LLM-only build
• Three planned AI data centers could add 14 billion gallons of off-site water use
• A WRI roundtable agreed to form a working group on AI procurement transparency
• Association Green IT projects AI at seven times the European sustainable budget by 2030
• QuickSort uses less energy than MergeSort on large datasets with many duplicates

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Policy, community and accountability

• The EU’s proposed labelling framework would make facility performance data public
• A West Virginia fund directed $4.5 million to workforce, preparedness and weatherization
• Massachusetts and Pennsylvania now require local approval for data centers
• California mandated water use disclosure for data centers
• AWS’s Australian Senate submission contains no absolute energy use figure
• One analysis puts NVIDIA scope 3 use emissions at up to 21 MtCO2e
• France, UNEP and ITU launched the Coalition for Sustainable AI
• Lenders weigh tenant credit, power dependency and obsolescence in European data center financing
• Khazna issued its first ESG report

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Green software and GreenOps

• HOLMES search software is one of 25 nominations for the German Ecodesign Award
• One organisation cut AI costs by 60% and emissions by 80% with a smaller default model
• Greenpixie’s Data Explorer calculates carbon data for any cloud region on AWS, Azure and GCP
• The open source SPRUCE project drew commitments to use and contribute
• GreenOps is shifting from reducing waste to preventing it at architecture stage
• AI batch tasks can be scheduled for lower demand and grid emissions
• The Green Software Foundation Policy Working Group pushes for accurate carbon, energy and water data

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Events

• Green IO London opened with a keynote on offshore wind powering the AI boom
• Green IO Paris runs 2 and 3 December 2026 under the theme “Bring AI and Tech Home”
• SF Tech Week hosted Green Software Foundation sessions on emissions estimation
• Data Center Nation Warsaw examined Poland’s grid readiness for high density AI
• Brussels Sustainable IT Days hosted the Sustainable IT Charter signing
• Green AI Day Stuttgart drew 300 participants
• A 4 November webinar covers applying the CLEER methodology

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Thanks to Nithish Bharat, Avnish Patankar, Sam Brundrett, Andrew Winston, Akshat Jain, Joe Speicher, Paul Churnock, Bridget Miles, James Rix, Vivek Mishra, José Segadães, Sanjaya Mariwala, Richard Tarboton, Ravi Jokhun, P M Bharadwaj, Anna Lerner Nesbitt, Beth Simone Noveck, Otmane NKAIRA, Zak Moore, Nick Pawson, Gísli Kr., Srinivas Varadarajan, Ryan Sholin, Nina Benoit, Chelsea M., Cristiane Passos P. Moura, Heather Clancy, Jogesh Ajay, Maike Conrads, Anita Schüttler, Manuel Alomar, Robert Keus, Vrushali Gaud, Ketan Joshi, Wendy Turner-Williams, Mark Butcher, Dr. Necip Gözüaçık, Nolwenn Godard, Alistair Alexander, James Martin, Apoorva S., Shaolei Ren, Boris Gamazaychikov, Wilco Burggraaf, Collins Wafula, Mani Bharath Bhadragiri, Arianna Kiarash, Géraldine Gandveau, Surabhi Tewari Jiwarajka, Gaël DUEZ, Mark Buss, Greg Stover, Claire Dorville, Dirk Mattys, Georgina M., Matthieu Poulard, Nissrine Rachdi, Oliver Penketh, Natallia Kachura, Mathieu KEIGNAERT, Edward Chinn, Navveen Balani, George Dritsanos, Kevin Leslie, Pascal Joly, Julien Nioche, Matt Hatley, Anthony Papargyris, Aydin Mir Mohammadi, Dr. Sasha Luccioni and everyone else who contributed insights to this edition. Find the full list of posts and voices on LinkedIn: