Technology groups have warned of the possibility of mobile phone and broadband blackouts this winter, which could leave people unable to make emergency calls in the event of power cuts.

Phone masts and the broadband network are powered by National Grid. While some parts of the infrastructure have back-up power supplies, such as diesel generators, that is by no means universal.

The 90,000 “last-mile” street cabinets, which provide much of the UK’s broadband, tend to have 30 minutes to a few hours of battery life but are not designed to go for prolonged periods without power. The 40,000 British phone masts have different levels of resilience.

In a stark warning, techUK, the technology trade association, and Mobile UK, which represents the mobile network operators, said

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