In recent months, headlines have painted an alarming picture of data centres draining precious water resources, particularly in the UK and Europe. But the real story is far more nuanced than the headlines suggest…
This blog aims to set the record straight. Following the recent article by the BBC ‘Concern UK’s AI ambitions could lead to water shortages’, Mark Acton, Head of Technical Due-Diligence at Future-tech breaks down how much water data centres actually use – especially in Europe, where the systems in place are vastly different from those often in the US.
From closed-loop chilled water systems to the limited, seasonal use of adiabatic cooling, we explore the facts versus the fiction. And, perhaps more importantly, we’ll highlight the crucial role data centres play in powering the digital services we all rely on every day.
Data Centre Chilled Water Cooling Systems: Do Data Centres Actually Use Much Water?
Despite the poorly researched and inaccurate reporting from the BBC and others, it is not correct to simply assume that all data centres, particularly those in the UK and Europe, are evaporating water and therefore ‘consuming’ it.
There are plenty of data centre cooling systems, traditional chilled water systems in data centres and many other types of buildings, which are closed loop systems and use very little water. Many appear to assume that chilled water cooling involves the use of significant quantities of water, it does not. Once the system is filled, the water remains in circulation, just as it does in a typical vehicle internal combustion engine cooling system or home heating system.
Data Centre Water Usage in Europe vs US
A lot of this concern about data centre water usage in the UK and Europe is a concern from the USA, and far less a European issue. A cynic might suggest that concerns raised by water companies in the UK that have failed to invest in their infrastructure are looking for somebody else to blame. Their arguments are typically based on invalid figures from operations in the USA and dependence on a general lack of understanding about how data centres reject heat.
Even if water usage were a real issue in Europe, golf courses consume more water than data centres and yet provide a far less valuable resource. If made to choose, would the majority of the population decide to close down golf courses, or the data centres that provide all of the digital services that they consume and have become largely dependent upon for social media, Gaming, Online Shopping, Entertainment, Banking etc.? It would be interesting to ask the general public, which they would prefer, a golf course or the loss of the online services including social media that they use from their phones and digital devices?
Can Data Centres be Cooled Without Water?
It is also worth noting that we typically use very different data centre cooling systems in Europe to those in the USA (where evaporative cooling towers are often employed), which do use a great deal of water and do create a genuine problem, especially in areas of water scarcity. These sites may even use water from aquifers below hot dry desert areas, which potentially take 1000’s of years to recover.
In most cases data centres do not ‘consume’ significant amounts of water in Europe. As highlighted above European and UK sites generally use ‘closed loop’ cooling circuits and get ‘free cooling’ in low ambient temperature conditions using what are effectively giant radiators, or DX refrigeration systems which use no water and rely on refrigerant gasses in a similar way to a domestic refrigerator.
If water is used for adiabatic cooling in Europe, it is generally only for used for supplemental cooling, particularly at times of peak seasonal heat for a few days per year, and low levels of water use. It is worth noting that Direct Liquid Cooling (DLC) systems, either Direct to Chip or Immersion, can also potentially employ evaporative cooling for heat rejection so do not automatically solve the water usage issue as some suggest.
According to a recent report by techUK, 64% of England’s data centres use less than 10,000 m³ of water per year – less than a typical leisure centre, and 89% of sites either measure water use or deploy systems that do not require water for cooling.
The Demand for Digital Services and Artificial Intelligence (AI)
Even if data centres in the UK did use water for evaporative cooling, remember that it is not the data centre itself that drives demand for water or power, it is us, the public. We consume digital services and are becoming increasingly dependent upon them. Our phones are merely windows into data centres and these digital services we all use are all based in data centres. It is the digital platforms we use and rely upon that drives data centre demand. It is naïve in the extreme to criticise data centres for water and power consumption while utilising the services that their customers provide. A little like blaming hotels for creating tourism demand – surely it is the other way round?
Data Centres that use water from totally renewable sources such as rivers and seawater etc. should be excluded from this area of concern. They are not dependent on water companies supplies and are not using water that has been processed into potable water, which obviously has a higher energy overhead and environmental impact. There is a strong argument for using non-potable water for evaporative cooling from sustainable supplies, as this can reduce power consumption and therefore reduce overall environmental impact. We have plenty of water in Northern Europe from renewable and sustainable sources should we choose to use them and despite some of the uninformed arguments being promoted, we do not truly ‘consume’ water, we merely move it around.
Finally, had an artificial intelligence (AI) tool been used to create this article (it was not), this piece would probably would have utilised a data centre in the USA consuming significant amounts of water from sources that are not sustainable. However, had that AI data centre been based in the UK (something the BBC seem to have a problem with), it would have been a different story with far less, if any, water usage involved.
Get Sustainable Data Centre Water Cooling with Future-tech
The narrative around data centre water usage has become clouded by misinformation, much of it rooted in outdated or overseas practices. In reality, most data centres in Europe use efficient closed-loop systems or refrigerant-based cooling with little to no water consumption.
If you’re planning, upgrading, or simply re-evaluating your data centre’s cooling strategy, make sure it’s based on facts – not fear. Before drawing conclusions based on headline figures or transatlantic comparisons, it’s vital to understand the actual technologies in use and the context in which they operate.
To better understand your data centre’s cooling systems – or if you’re planning a new facility and want to explore water-efficient or non-water-based cooling options, we’re here to help. We work with clients across the UK and Europe to design, assess, and optimise cooling solutions that are sustainable, cost-effective, and future-ready.
Get in touch with our team of expert engineers today to find out more.