The UK government is urging citizens to prepare for potential emergencies by stockpiling essential supplies to be self-sufficient for at least 72 hours. This advice aligns with a “Black Sky” event plan, which refers to a widespread disruption, such as a power outage or cyber attack, that could knock out services and shops for several days.
UK Government Urges 72-Hour ‘Black Sky’ Preparations
According to officials, the campaign is not based on any specific intelligence of an imminent crisis, but rather on building national resilience so that public services are not overwhelmed.
The advice for a 72-hour preparation period is driven by the assessment from the National Energy System Operator (Neso) that power is likely to be restored within two to three days following a major blackout. This timeframe is based on recent events, such as a mass blackout that affected Spain, Portugal, and south-western France in April 2025.
A “Black Sky” event is considered to be more than just a loss of electricity. Lord Harris, chair of the UK’s National Preparedness Commission, explained that such an event would likely stop the water supply, as pumping stations require electricity. He added that sewage systems would also be at risk of solidifying and causing blockages and backups, posing a significant public health hazard.
As part of the national preparedness, the BBC has its own Black Sky plan. In the event of a severe disruption, approximately 100 staff members would run a dedicated emergency radio studio. This studio would be equipped with secure communication lines, independent of the internet, and have its own fuel, water, and food to operate without resupply for at least three days, broadcasting pre-arranged government messaging.
