Demand for data centres has exploded over the past five years due to increased adoption of AI and cloud computing, both of which require massive amounts of computing power.

But what is a data centre, and how does it work?

City AM was invited inside one of Virgin Media 02 (VM02)’s largest data centres in the UK, located in Slough, to find out.

As Thomas Finch, VM02’s technical site operations manager, explained, the facility is the operator’s largest mobile data centre in the UK.

“Everything you do on your mobile phone – voice calls, texts, whatsapp, social media – passes through this data centre”, he said.

Increased demand

With millions of people relying on their mobile and broadband services daily, data storage and processing demand has skyrocketed.

A recent report by TechUK estimated that the UK data centre sector could grow tenfold by 2035, boosting the economy by £44bn, creating 40,000 jobs in the process.

Currently, UK data centres contribute £4.7bn in gross value added (GVA) and generate £540m in tax revenue.

The UK government recently classified data centres as critical national infrastructure in response to this boom.

Network testing

The infrastructure supporting this data hub is vast, including a network of fibre-optic cables connecting users nationwide.

VM02’s site houses several ‘faraday cages’, which are shielded enclosures designed used for network testing.

These allow engineers to conduct controlled 3G, 4G and 5G tests without interference.

Due to their controlled environment, no cellular signals penetrate these spaces.

They, therefore, require landlines for communication inside.

Apple also operates its own Faraday cage within this VM02 centre to test its services securely.

Powering a city’s worth of data

A critical element of these data centres is resilience, which is built into the infrastructure from the beginning.

The site operates with multiple layers of redundancy to ensure its continuous service and reduce failures.

In the event of an external power failure, the site’s UPS (uninterruptible power supply) kicks in, supplying direct current power until generators take over.

Its generators are capable of powering two of three residential streets, with 2,000 litres of diesel on-site to sustain operations during an outage.

To put it into perspective, while a typical home uses 300KW of energy a year, VM02’s consumes the same amount in just an hour.

Regular maintenance is also essential.