Cooling the Debate: Data Centres in the UK

Data centres power our emails, streaming services, banking systems and the growing wave of AI innovation, forming the digital infrastructure that underpins almost every aspect of modern life. Often referred to as the unsung heroes of the modern economy, datacentres are now under fire as a purported enemy to the environment.  

Headlines about data centres “draining water supplies” have fuelled growing concern about the sustainability of our digital future – and the concern is fair, and understandable. 

Around the world, there are documented examples of data centres consuming significant quantities of water for cooling. However, much of the evidence driving this debate comes from regions facing very different climatic challenges to those found in the UK. While water-intensive ‘evaporative’ cooling systems are widely used in hotter parts of the world like Texas and Arizona in the USA, almost all UK data centres use closed-loop systems and barely use any water at all.  

When discussing the role of sustainable digital infrastructure in the UK, it’s important to focus on the realities of how UK data centres operate, rather than assumptions based on practices in very different climates and operating environments. 

Alongside these operational realities, the sector is also subject to an increasing number of sustainability commitments, efficiency standards and industry-led initiatives designed to improve transparency and environmental performance.

Do Data Centres Really Use Excessive Amounts of Water? 

Much of the understandable concern around data centre water consumption originates from practices used in hotter regions, particularly parts of the United States. In states such as Texas and Arizona, high temperatures mean that huge amounts of electricity are required to chill water to the low temperatures needed to cool a datacentre, and it is more cost effective to use evaporative cooling instead.  

However, the UK operates very differently – our climate is vastly cooler. Most UK facilities use closed-loop chiller systems, where the same water – combined with a chemical called glycol – circulates around the system. This is much like a central heating system in reverse. 

Many also don’t use chillers at all when the outside temperature is below 15 degrees and simply draw the cold air from outside into the building through layers of air filters – maximising energy efficiency and meaning that no chillers are required for much of the year.  

According to research from techUK and the Environment Agency, 64% of England’s data centres use less than 10,000m³ of water per year – much less than a typical leisure centre or golf course. The same research also found that only 5% of UK based facilities use water intensive evaporative cooling.  

Britain is well positioned to support highly efficient data centre operations that minimise both water and energy consumption, while maintaining the performance and resilience required to meet growing digital demand. 

The Sovereignty Debate 

There are a lot of stigmas around datacentre construction in the UK right now, driven by misinformation around water consumption and a more legitimate debate about their significant energy requirements. 

There are other factors that are equally important to consider. Demand for AI and digital services is growing across every sector, from legal and healthcare to manufacturing, financial services, and public administration. If the UK does not have the capacity to support these services domestically, they will inevitably be delivered elsewhere. That could mean losing investment, highly skilled jobs, and opportunities for economic growth, while also reducing the UK’s ability to influence and shape the technologies that will underpin its future competitiveness. In a global digital economy, the question is not whether these services will exist, but where they will be hosted and developed. Ensuring the UK has the infrastructure to support AI innovation is therefore an economic and strategic consideration as much as an environmental one. 

An increasingly uncertain geopolitical environment adds another dimension to the debate. As more critical services are delivered through digital infrastructure, dependence on technology hosted overseas can create resilience challenges. When essential services such as banking, healthcare, and public administration rely on infrastructure connected through international networks and undersea cables, disruptions beyond the UK’s control can have significant consequences. Building domestic capability is not simply about supporting growth, but also about strengthening national resilience and maintaining greater control over critical digital infrastructure. 

The risks are not purely theoretical. In October 2025, an outage affecting Amazon Web Services took out online services used by organisations including Lloyds Banking Group and HMRC, highlighting how issues within a relatively small number of globally concentrated cloud providers can have widespread impacts. The incident prompted questions from MPs about the UK’s reliance on infrastructure hosted overseas and reinforced the growing importance of digital sovereignty, resilience, and infrastructure diversity. 

Where Do We Go from Here? The Future of Sustainable Data Centres 

While much of the public conversation centres on water use, the biggest sustainability gains lie in energy efficiency. Modern UK data centres achieve industry-leading Power Usage Effectiveness (PUE) ratios as low as 1.14, significantly outperforming traditional on-premises solutions and dispelling the idea that cloud migration is inherently more resource-heavy. In reality, moving workloads from inefficient server rooms into optimised environments often results in lower overall energy consumption. 

The UK also benefits from a favourable climate, allowing operators to minimise water-intensive cooling methods used abroad and instead rely on advanced technologies such as air cooling, direct liquid cooling for high-density AI, and systems that only use water during rare heat events. Ongoing investments in renewable energy, heat reuse initiatives and AI-powered optimisation will further accelerate this progress – creating infrastructure that is both resilient and sustainable. 

Looking ahead, businesses have an important role to play in shaping this transition. Choosing the right data centre partners is no longer solely about performance or cost; it’s about understanding their commitments to sustainability, transparency and compliance with industry frameworks like the Climate Neutral Data Centre Pact, ISO 46001 and BS EN 50600. Organisations should also review their own IT strategy – many still operate ageing on-premises servers that consume far more power than consolidated, cloud-based or colocation alternatives. Reducing your digital carbon footprint isn’t only possible; done well, it often improves security, resilience and operational efficiency at the same time. 

Data centres are critical to economic growth, innovation and AI adoption, but they must evolve responsibly. With the UK’s climate advantages, industry leadership and focus on net-zero, the future of digital infrastructure doesn’t need to come at the environment’s expense – if we make the right decisions now. 

If you’d like to understand what this means for your organisation – from sustainable data centre options to cloud migration – we’re happy to talk. Get in touch with our team today.