Executive Summary
- Extreme heat and wildfires halting London’s railway lines are a critical warning that traditional climates are vanishing and that changes the future of data centres.
- Free-air cooling will become a liability with the extreme heat and so developers will fully embrace closed-loop liquid cooling and environmental isolation.
- The days of data centres weathering summer spikes and storms are over and now infrastructure needs to be built and adapted to ignore them.
If the heatwave isn’t already enough of a reminder of our changing climate, the images from East London last night will be your stark reminder. Temperatures hit 35 degrees Celsius for the sixth day in a row and that has had an impact on infrastructure. A fallen tree caused an electrical fire, which broke out at a railway embankment in East London, with one house alight, another suffering damage to the extension, and around 30 gardens affected, as well as the embankment. Thankfully, no injuries have been reported so far, though the blaze was so serous 25 fire engines and 125 firefighters were called to the scene to tackle the fire.
For the public, aside from those whose homes were damaged and who were evacuated, this was a commuting headache, but this is a screeching alarm bell for the data centre industry. If a steel-and-stone rail network that transports millions of tons can be halted by ambient heat and fire risk, then what could it do to the fragile, power-dense digital infrastructure humming right next to it?
The safe zone myth and the demise of free cooling
A myth sat in the industry; the facilities built in Frankfruit, London, Amsterdam and Paris were safe in their zone because extreme environmental threats were anomalies, but that assumption has evaporated. Our climates are getting hotter, the wildfire risk is greater and the industry needs to address it pronto.
With these growing risks comes the downfall of the industry’s love affair with “free air” cooling; when external air carries extreme heat and microscopically fine ash, smoke and particulate matter from a nearby wildfire, drawing that into a data centre to cool down the equipment is infrastructure roulette. Sooner than we want, we are approaching a fork in the road where the ambient air outside is too hot, ditry and volatile to be trusted. The future of cooling realistically belongs to closed-loop cooling systems that isolate the IT environment from any potential hostile external atmosphere.
The grid is shared and starved
When rail operators cut power to lines so firefighters can tackle the fire, it highlights the one critical vulnerability we have: interdependency. Data centres don’t exist in a vacuum, as there are grids supplying power under stress during heatwaves – that stress accumulating from industrial cooling, infrastructure emergencies and domestic air conditioning. When emergencies such as a fire happen, the grid prioritises life safety over uptime, which means when it really boils down to it, relying solely on the grid for power, especially during a prolonged heatwave, is a huge risk and certainty that there will be downtime as our summers get hotter.
Data centres need to ignore the storm
Data centres are currently being designed to weather the storm but they need to be designed to ignore them and not be affected by them, no matter how extreme the weather gets (with room for error, of course). This would take place in the form of structural shifts, for example:
- Shifting towards mimicking the exterior of critical military infrastructure, which is resilient against ambient heat plumes and smoke infiltration.
- Utilise predictive modelling to shift workloads out of heat-stressed geographic regions before peaks, to prevent rather than having to react after the chiller failure.
- Fully embracing immersion and direct-to-chip liquid cooling as the firewall against a volatile external atmosphere.
London’s incident is a preview of what is to come as our climate gets hotter. The data centre industry does like to think of itself as the invisible, invincible backbone of the digital modern world, but as the weather becomes hotter and more extreme, the line between digital uptime and physical meltdown gets pretty thin. It’s time to build infrastructures that ignore the heat and engineer for summers that are already here.
