Are UK data centres ready for climate change?

A lot of AI infrastructure coverage focuses on money and power. There is a lot less attention on a simpler risk: whether the physical buildings can withstand the UK climate they are currently operating in. Dave Kimberley, CEO of Krystal, speaks below in his thought leadership piece on why this risk is going largely unmanaged. 

Right now, every conversation about UK data centres seems to start and end with power; whether the grid can supply enough of it to keep pace with AI. The UK has set a target of 6 GW of AI capable data centre capacity by 2030, and the connection queue for new projects has ballooned past 125 GW.

But there is an additional question lurking underneath the first one, and it is receiving almost no attention: can these facilities survive our changing weather while they are doing it?

In July 2026, an extended period of unusually high temperatures caused the Dawn supercomputer at the University of Cambridge to be knocked off line for nine days. But it wasn’t the first time something like this has happened. 

In 2022, record breaking 40°C temperatures forced both Google and Oracle to shut down parts of their data centres in London after cooling systems were unable to maintain safe operating temperatures. And that very same summer, failures in the cooling system at Guy’s and St Thomas’ NHS Foundation Trust resulted in staff being locked out of patient records, costing the NHS an estimated £1.4 million.

But what if these weren’t one off accidents, but previews of what was to come?

Data centres are now recognised as part of the UK's Critical National Infrastructure (CNI), reflecting their essential role in supporting public services, healthcare, finance and the wider economy. Which places them in the same bracket as power stations and water treatment works. Yet, climate adaptation policy hasn’t caught up with that designation. The Climate Change Committee’s recent ‘Well Adapted UK’ report names hospitals, schools and care homes as priorities for heat resilience. Data centres, despite sitting in the same CNI bracket as power stations, are barely mentioned. The next National Adaptation Programme, due in 2028, is a clear moment for that gap to be addressed, but it means the sector is currently expected to self-regulate its own standards of resilience. 

The systems built to keep the country’s websites, hospitals, public services and banks up and running were designed and built for a climate that we don’t live in anymore. As the extreme temperatures become more routine than remarkable, UK based, carbon neutral hosting provider Krystal, considers a question that needs asking sooner rather than later: is the UK’s infrastructure ready for the weather to come?

Data centres run hot by their very design. With racks of servers working round the clock, it is no surprise that constant heat is generated, and cooling systems are required around the clock to stop that build up of heat becoming a problem. Toeing that line has always assumed a predictable British climate, but that assumption is becoming vastly outdated.

techUK’s ‘Futureproofing Digital Infrastructure’ report now identifies heatwaves, temperature variability, and water scarcity are the most likely climate risks that will disrupt data centres in the UK, as well as flooding and power grid strain. But the hot and dry weather doesn’t just force cooling systems to work harder, it also pushes them to the limits they were built to withstand. Many existing facilities were designed around historical UK climate assumptions. As ambient temperatures rise, cooling systems spend less time operating in their most efficient modes and increasingly rely on mechanical cooling, reducing resilience and leaving less headroom during prolonged heatwaves.

Data from the Met Office shows how quickly this is accelerating: the number of days in the UK exceeding 28°C has doubled in recent years, while days reaching 30°C or higher has trebled. Thresholds that data centre cooling systems were calibrated against a decade ago are now being breached as the routine, rather than the exception. 

There is also the risks associated with power. Extreme temperatures reduce the amount of power overhead transmission lines can safely carry, just as electricity demand for cooling rises, right at the moment demand for cooling – and electricity in general – can experience a spike. Losing cooling systems and grid power at the same time, and a facility can go offline in an instant. 

And last, but certainly not least, there is the risk of flooding – a very different, but equally serious threat. A growing number of UK data centres sit in zones that are at risk of flooding, or are serviced by old draining systems. Water and moisture penetration can knock power, cooling and physical hardware off line in one fell swoop, as opposed to the gradual degradation caused by heat.

So, is UK infrastructure built for a hotter future?

The short answer is, yes, and partially. New facilities built in the UK are being designed with higher temperature tolerances in mind, with free cooling and renewable power considered from day one. However, that doesn’t account for the large proportion of the country’s data centres that predate the record breaking summers we seem to experience every year. Retrofitting an existing facility for a climate that is hotter, wetter and more volatile is possible, but it takes a lot of investment, and requires operators to be honest about where gaps are – rather than waiting for the next heatwave to find them.

Thankfully, the industry is moving forward rather than standing still. The response to the increased climate risk is being felt in a few key areas:

• Redundant, over specified cooling: rather than sizing cooling capacity for ‘standard’ conditions, operators with resilience in mind are designing in headroom for sustained extreme heat. This means that a single failed unit won’t snowball into a complete outage.

• Environmental monitoring in real time: having alert thresholds calibrated for temperatures of years gone by is becoming redundant as the climate gets hotter. Facilities need monitoring done in real time that flags problems early enough to act, as opposed to after servers have already started to shut down.

• Power that is renewable and resilient: having providers matched to renewable energy with robust backup facilities will be much better placed to keep cooling systems running, even if there is strain on the grid.

• Regular stress testing: this must be done against worst case scenarios, not historical averages. As the last few years have shown us, record breaking is fast becoming the average.

Questions to ask your host

If you are a business owner that doesn’t operate your own infrastructure, the resilience of your storage against an extreme climate will come down almost entirely to your provider. Here are a few questions worth asking, whether you are starting looking from scratch or thinking of changing:

Where is my data actually located? And what is the flood and heat risk? If they can’t (or won’t) answer, then be wary.

What is the uptime guarantee, and how is it backed up? A headline worthy SLA isn’t worth much if it is supported by a single cooling system. 

What are your energy sources? Can they scale under strain? 

Have they experienced past incidents, and if so, are they open about them? It is almost a given that every provider will deal with the extreme weather at some point. But what separates the resilient providers is those who are upfront about incidents and what they did afterwards.

Is your infrastructure built for UK climate and conditions? Or has it been adapted from models in milder and more predictable climates?

Dave Kimberley, CEO at Krystal, shares what he thinks for the future of data centres in current climates:

‘The majority – if not everybody – in this industry can quote you an uptime percentage to at least two decimal places. But if you ask what temperature range that number caters to, then some won’t be as vocal. And that is where the real gap is – resilience is so often reported as an average, but when it comes to a drastically changing climate, averages lose their meaning.

‘'A data centre doesn’t fail on a bad month – it fails on a single extreme day. Until ‘built for extremes’ is ‘the’ standard to which data centres are actually created for, businesses are inheriting climate risk without even knowing they have taken it on.

‘We spend a lot of time talking about whether the grid can power the AI boom. Nobody’s asking the equally urgent question of will the buildings themselves still be standing, thermally, by the time that power arrives. Retrofitting for climate isn’t optional anymore, but way overdue.’