Your Reading List & recommendations

O2 cools down data centres to save energy as 4G and 5G usage hots up

As lockdown eases and mobile data use sees 4G and 5G consumption reaching new records, we’re rolling out new smart cooling technology to better control the temperatures at our data centres and boost the efficiency of our networks. This will help deliver energy savings equivalent to one million kilograms of CO2 year-on-year.

We’ve carried record amounts of data over the last 12 months – up 89% from the pre-pandemic average in 2019 – and our appetite for mobile data will only keep growing. This soaring data demand also increases pressure on our data centres and creates carbon emissions from the hot equipment that needs cooling.

To help build a greener network, we’re radically overhauling these data centres and core network sites with brand new, energy-efficient cooling equipment. These new additions will regulate temperatures at the sites that keep our mobile network running. They use the natural cold air outside to help cool data equipment when it actually needs it, rather than relying solely on traditional electric-powered air conditioning. Using fresh air also reduces our reliance on polluting refrigerant gasses.

Our network upgrades are set to save the equivalent of 1m kilos of CO2 year-on-year.

We’re also the first major network to roll out new management software from EkkoSense across our whole estate. The software uses smart sensors fitted to data centre equipment to monitor exactly how much cooling each site needs at any one time and reports back on how to optimise cooling as demand changes. This not only helps make sure each site operates as efficiently as possible, it also helps identify any issues and prevents overcooling or overheating. The new EkkoSense software is expected to deliver energy savings equivalent to one million kilograms of CO2 year-on-year.

We’ve already upgraded around 70% of our core network sites with this equipment and EkkoSense’s data centre optimisation software, delivering an energy saving of between 15% and 20% per site. This is equivalent to 678,000 kilograms of CO2 in its first pro-rate year of use.

“Our number one priority is keeping customers connected, but that can’t be at the expense of the environment. Data centre cooling is a great example: the more data we use, the hotter the centres can become. Historically networks have relied on air con, but the UK has plenty of fresh, cold air that does the same job – so we’re getting rid of old kit and using energy in a smarter way. Investing in upgrading our network will help us hit our efficiency targets as we head towards net zero by 2025 – without compromising on the service we provide.”

Tracey Herald, Head of Corporate Responsibility & Sustainability at O2


“We’re delighted that O2 chose EkkoSense to help them cool their data centres more efficiently and deliver energy savings at a time when demands on their critical facilities have never been so intense. Our software’s ability to capture and analyse O2’s critical power, space and cooling information in real-time gives their data centre team access to much more powerful optimisation capabilities, as they progress towards net zero.”

Dean Boyle, CEO at EkkoSense

 Turning masts on snooze mode and running on renewables – a greener network

We’re investing more than ever in our network to improve coverage and experience for all of our customers across the UK. This is matching growing demand with our industry-leading green ambitions. The various energy-efficient enhancements we’ve introduced are one of the reasons our network is now around 82% more energy efficient than it was in 2015.

Our operations are powered by 100% renewable electricity wherever we directly control the bill. After starting our renewable energy procurement in 2008, we’ve since invested approximately £400m in renewable energy supply and are now going even further by working with landlords to encourage the switch to renewables on third-party sites, where we don’t own the energy bill. Currently, 70% of our total estate is powered on renewable energy sources.

Our commitment to a greener future

In 2020, we became the only mobile network operator to commit to net zero by 2025, while working with supply chain partners to reduce emissions by 30% in the next five years. We’ve already made significant progress against these goals, including:

  • Reducing carbon emissions in our operations by 29% since 2015
  • Achieving a 35% carbon reduction in emissions in our supply chain since 2016 – already exceeding the supply chain target

Want to find out more about our commitment to becoming net-zero? Click here.


All articles


Public sector

Safe & secure


Tech advice

Work smarter