Corporate sustainability initiatives increasingly are finding their way into the data center. But many CIOs who invest in and deploy leading-edge carbon-cutting technology aren\u2019t even aware they\u2019re taking climate action. They\u2019re just trying to improve the bottom line.\n\nThat puts CIOs in an enviable position. In most corners of the enterprise, ESG decision-making necessitates squaring potential climate benefits with the added expense, uncertainty and disruption of next-generation fuels, materials and processes.\n\nBut IT decision-makers have opportunities to skirt that problem in the data center, which is responsible for about two percent of US greenhouse gas emissions. Emerging innovations are helping to convert their massive resource-intensive server complexes into a rare tradeoff-free front in the sustainability war, where reductions in carbon emissions often go hand in hand with lower costs.\n\nIncreasingly, it\u2019s a front worthy of investment. Supply-side concerns like elevated fuel prices and geopolitical instabilities are only part of the motivation. Power is already the data center\u2019s largest expense. And the seemingly insatiable desire to glean more insights from more data is driving denser deployments of racks stuffed with evermore power-hungry CPUs and GPUs.\n\nTo make matters worse, data centers are reaching the point that the energy required to cool racks packed with those brawny servers is rising faster than what\u2019s needed to run them.\n\nBy some estimates, as much as 40 percent of a data center\u2019s power budget is now devoted to cooling. To try and reverse the trend, many facilities managers have adopted evaporative cooling. That can help trim electricity demands from HVAC units and on-board fans. But it requires huge amounts of water \u2013 collectively, about 174 million gallons per year in the US.\n\nThat\u2019s, like, unsustainable. Which is why cost- and sustainability-minded CIOs are looking beyond evaporative cooling.\n\n\u201cThe way we\u2019ve been cooling data centers is going to have to change,\u201d said Scott Tease, Vice President and General Manager of HPC and AI at Lenovo. \u201cTraditional air cooling just can\u2019t keep up. And we don\u2019t have the water anymore to supply the massive amounts that evaporative cooling requires. It\u2019s a big, big problem.\u201d\n\nMore enterprises recognize that reducing water usage in the data center is becoming as urgent as slashing fossil fuel consumption. AWS, for one, is already getting a jump on both. At its re:Invent event late last month, the world\u2019s largest cloud provider pledged to be water-positive by 2030. As well, the company reiterated its commitment to power 100 percent of operations with renewable energy by 2030. During his keynote, attendees cheered when CEO Adam Selipsky told them that the company was already more than 85 percent of the way there.\n\n\u201cPlease everyone, get involved,\u201d Selipsky implored the crowd. \u201cIt\u2019s a problem for all of us.\u201d\n\nAI to minimize the cost of AI\n\nAs with most any data center upgrade, energy-efficient options are far more varied and plentiful if you\u2019re starting from scratch with a new facility, whether it\u2019s on-premise, collocated or in the cloud. That said, CIOs have compelling options for cutting carbon emissions \u2013 and lowering energy costs \u2013 that are effective regardless of whether they\u2019re deployed in new sites or on individual server upgrades in existing racks.\n\nIronically, one increasingly popular way to reverse the impact of mushrooming AI and machine learning on data center power demand is with more AI and ML: that is, software and services to help IT optimize storage and workloads across existing assets to ensure the most climate-friendly, cost-effective distributions.\n\nAnthony Behan, Managing Director of Cloudera\u2019s Telecommunications, Media and Entertainment efforts, said the transition to high-powered 5G has made his customers laser-focused on minimizing data transfers to drive power savings \u2013 and, as a consequence, cost \u2013 by pushing data workloads closer to where the data is collected and stored.\n\n\u201cIn telecommunications, every single C-level executive has cost as a line item on their performance review,\u201d Behan said. \u201cIt\u2019s something that they\u2019re constantly thinking about. So this tends to be what lights their eyes up.\u201d\n\nLiquid cooling\n\nIT decision-makers can make a big dent in power demands with liquid cooling, which is quickly rising as a leading alternative. It\u2019s far more efficient than air cooling and even evaporative cooling. Suppliers say they can save as much as 40 percent on the energy bill for cooling and enable much higher-density server and rack deployments.\n\nAnd because liquid cooling systems are closed-looped, there\u2019s no water bill.\n\nThe technology has been used to cool supercomputers for years. Only recently, it\u2019s begun waterfalling into everyday data centers. Suppliers now offer liquid cooling implementations for racks, servers and even individual components. Nvidia, for example, announced plans to begin offering liquid-cooled GPUs this winter.\n\nIntel, the provider of literally the other hottest server component, has been working for several years to help ensure viable liquid cooling options for the data center. In 2019, it partnered with pioneer Lenovo to pair Lenovo\u2019s Neptune liquid cooling technology and TruScale infrastructure platform with Intel\u2019s Xeon Scalable server hardware for HPC and AI applications.\n\nMore recently, Intel has announced efforts with other suppliers, including Submer and Green Revolution Cooling, as well as a $700 million investment in a liquid cooling R&D facility in Oregon. \n\nStarting from scratch\n\nCIOs who are looking to deploy a new site, whether that be on-premise, with a colocation provider or cloud vendor, can find opportunities to reuse the heat that liquid cooling implementations diffuse.\n\nCloud&Heat, for example, offers self-contained data centers that can warm nearby office buildings in the winter. If you\u2019re looking for other diffused heat applications, you can see what others are doing on this map of projects. The German provider of sustainable cloud and on-premise technologies coordinates the mapping effort under the auspices of the Open Compute Project.\n\nOne of the sites on the reuse map, in fact, is a Montreal colocation facility being developed by QScale, a startup offering high-density data center facilities. The first phase, which is expected to come online in early 2023, checks most of the sustainability boxes. For example, it is:\n\n\u201cWe\u2019re all used to sustainable things being more expensive,\u201d said Martin Bouchard, Co-founder and CEO of QScale. \u201cBut we\u2019re not more expensive than a plain vanilla, dirty data center. So you can have sustainable, clean carbon output and be super-efficient all at the same time.\u201d\n\nThat should be music to CIOs\u2019 ears \u2013 regardless of whether they\u2019re working to make their data centers more sustainable. Or just cutting costs.