Power Cut Statement - 10 August, 8.30am

A National Grid Electricity System Operator spokesperson said: “We appreciate the disruption caused by yesterday’s power outage and investigations have continued overnight to better understand the situation.

“As the Electricity System Operator we do not generate power directly, but use the power made available by the industry to manage the system and balance supply and demand. The root cause of yesterday’s issue was not with our system but was a rare and unusual event, the almost simultaneous loss of two large generators, one gas and one offshore wind, at 16.54pm. We are still working with the generators to understand what caused the generation to be lost. 

“Following the event, the other generators on the network responded to the loss by increasing their output as expected. However due to the scale of the generation losses this was not sufficient, and to protect the network and ensure restoration to normal operation could be completed as quickly as possible, a backup protection system was triggered which disconnects selected demand across GB. 

“Following the incident, the system was secured, and the Electricity System Operator gave the all clear to the Distribution Network Operators (NDOs), power companies who are responsible for supply at a local level, within 15mins, so that they could start to restore demand. All demand was reconnected by the DNOS by 17.40pm. We appreciate the disruption cause and will continue to investigate, with the generators involved and wider stakeholders, to understand the lessons learned.”