Data centre

A data centre is a building or room that houses a company's entire computing infrastructure. Depending on the size of the company, data centres are spread across different buildings, countries and continents. In smaller installations, it can simply be a server room or a server rack.

A data centre bundles IT resources and processes large volumes of data – for banks, universities, cloud providers, search engines or for hosting online shops, for example. To keep data processing reliable and avoid outages, all important components are usually duplicated (redundancy). If a device fails, a backup system takes over immediately.

Special requirements for a data centre

Building a data centre requires a lot of planning, because the sensitive server technology has to be protected – after all, countless processes depend on a smoothly running IT infrastructure. Besides the rooms for the IT systems, technology is needed for air conditioning, power supply, emergency power and fire protection. Cooling in particular is a key issue: the high power density generates a lot of heat, which can lead to outages or, in the worst case, fires. The hot aisle/cold aisle principle is often used: the servers draw in cooled air at the front and release warm air at the back, which is then extracted in a controlled way. For very powerful systems, for example for AI applications, liquid cooling is increasingly used.

Because operations are threatened not only by heat or short circuits, but also by power failures, natural events, cyberattacks and unauthorised access, security plays a central role. Access is strictly controlled, and systems are monitored around the clock. In the event of fire, special extinguishing systems are used that smother fires with inert gases, for example, without damaging the hardware – conventional extinguishing water would cause more damage than the fire itself. Halons, which used to be common, have long been banned in the EU because of their ozone-depleting effect.

Power consumption and energy efficiency: costly to run

Data centres consume a lot of electricity: in Germany, demand was most recently estimated by the Borderstep Institute at around 18 terawatt hours per year – and rising, not least because of AI applications. A large part of this goes not into computing power but into cooling and infrastructure. How efficiently a data centre works is described by the PUE (Power Usage Effectiveness) metric. In Germany, the Energy Efficiency Act has prescribed minimum standards for energy efficiency and waste heat use since 2023. Large providers such as Google also invest in renewable energy and more efficient cooling.

Cloud or your own data centre?

The cloud has become increasingly important as an alternative to running your own data centre. Companies rent computing power and storage from providers such as AWS, Microsoft Azure or Google Cloud, which in turn operate large data centres. The cloud is flexibly scalable, accessible from anywhere and avoids high investment. Your own data centre, on the other hand, offers maximum control over data and hardware, but is expensive and difficult to scale. Many companies therefore opt for hybrid solutions or colocation, where their own servers are housed in someone else's data centre. For online shops, location, loading time and data protection are particularly important: where the servers are located affects both performance and which data protection law applies. In any case, IT security is key.