BT Group network chiefs forecast significant cost and energy savings from shutting down legacy network technology in the coming years, including the sunsetting of 3G, discontinuing use of old fixed systems and selling unused exchange sites.

In a media event outlining progress towards a range of network modernisation goals, the EE parent detailed benefits from slashing the use of outdated technology it deems power hungry and offering limited benefits to users.

This drive includes closing down 3G technology in 2024, a goal announced by the company in 2021.

It has already switched-off 3G femotocells and aims to get remaining former customers of Orange and T-Mobile UK, which merged to form the operator which became EE, off the technology this year.

BT CTIO Howard Watson (pictured) noted “it is quite a big programme for us over the next few years, but with significant benefits”.

He added it was in the process contacting customers on legacy 3G plans to “gently encourage them to move to 4G or 5G” with some of these “out of contract for nearly 20 years”.

Watson noted 3G infrastructure consumed between 30 per cent and 35 per cent of the power used across its mobile network, with only 2.2 per cent of downlink traffic currently carried on it. Once switched off, BT will also be able to free-up the spectrum.

BT estimates decommissioning legacy fixed and mobile networks will save 550GWh of energy consumption. This, together with its other modernisation efforts, are predicted to deliver £500 million in savings by the end of the decade.

During the event, BT also outlined progress in its 5G rollout, where the company claimed to have hit a target of covering half of the UK’s population a year earlier than its original 2023 target and started moving customers onto its new core. It aims to provide 5G “anywhere” in the country by 2028.

As part of efforts to deliver the latest network technology, BT noted it was assessing high altitude coverage delivery systems and LEO satellite systems. However, Watson cautioned he didn’t think the latter would likely ever deliver more than 2 per cent of the UK’s broadband needs.