London blackout leaves businesses facing ‘domino effect’ of disruption as thousands left without power

Businesses caught up in a major power cut across central London face a “domino effect” of disruption stretching far beyond a few hours of lost trading, a data analyst has warned.

Offices across the City of London were plunged into darkness earlier today as a major power cut swept across the capital.

UK Power Networks said a fault on an underground electricity cable affected 32 postcodes, disrupting pharmacies, traffic signals and train departure boards.

Power was restored by the late morning, but businesses were left without electricity for over an hour — potentially disrupting everything from card payments and refrigerated stock to telecommunications and safety systems.

Rebalance Earth, a nature investment company, has mapped the concentration of essential services whose electricity supplies are at risk from flooding.

Gabriella Edghill, a geospatial analyst at the company, warned that widespread power loss could have “cascading impacts” across London’s businesses and infrastructure.

“Retail, hospitality, service businesses, even grocery stores... can end up just losing revenue from lost trading days or even lost stock,” Ms Edghill said. “In terms of supply chain disruption, that can also be a thing... all of this can kind of trigger a cascading effect downstream of the supply chain.”

And the consequences, she warned, can extend beyond lost revenue.

The area affected by Monday's power outage

UK Power Networks

“Emergency lighting, fire alarms, ventilation systems, things like that can get disrupted and cause hazards.”

Rebalance Earth estimates more than 2,500 businesses across London are at risk from flooding affecting the power grid, with the potential financial cost reaching £14.6m a day.

While its research focuses on flooding rather than power cuts caused by cable faults, its analysis highlights the potential economic exposure when electricity infrastructure fails.

Business group BusinessLDN said the outage should serve as a warning over the importance of the capital’s energy resilience.

Muniya Barua, deputy chief executive at BusinessLDN, said: “While it’s good to see that power was restored so quickly after this morning’s outage, the disruption it caused to firms and transport networks underlines the importance of reliable energy supplies to growth across the capital.

“It’s vital that lessons are learned from this incident to mitigate the risks of future power cuts.

“Ensuring London’s electricity network is resilient is key to giving firms peace of mind and bolstering the capital’s reputation as the best place in the world to do business.”

The 32 different postcodes affected by the power outage this morning were: E1 5, E1 6, E1 7, E2 0, E2 8, E2 9, E5 0, E8 1, E8 2, E8 3, E8 4, E9 5, E9 6, E9 7, EC2A 2, EC2A 3, EC2A 4, EC2M 3, EC2M 4, EC3A 7, IG3 8, N1 0, N1 1, N1 2, N1 3, N1 4, N1 5, N1 7, N1 8, N5 2, NW8 7, W2 3.

Cynthia, who works at Apex Pharmacy on Essex Road, told The Standard that the outage would leave many of their patients without their prescriptions.

The pharmacy usually orders the following day’s medication every morning - but today’s power cut meant that the staff were unable to use the pharmacy computer.

As such, Cynthia said that many customers will no longer be able to collect their prescriptions tomorrow. Cynthia, who lives in the area, said that the outage also affected her home.

Transport for London confirmed that the power failure had impacted some CCTV and traffic signals in the area.

Rail and bus services were operating as usual, though they were said to be taking extra care.

The Great Northern line was affected, with trains unable to stop at Essex Road as the platform lighting cut off, while the departure board at Liverpool Street Station was cast in darkness.

A UKPN spokesperson said: “We apologise for the inconvenience after a fault developed on our underground network in the Shoreditch area at 10.30am today.

“Power supplies were interrupted to several thousand properties and our engineers worked as quickly as is safely possible to reroute electricity to those affected, in stages, until 11.08am when all were back on supply.”