Chaos hit large parts of Northern Ireland on Thursday afternoon when 100,000 were left without power in a major blackout.
Homes and businesses were without power in Belfast and parts of Co Down from just before 2pm for almost an hour.
Traffic lights stopped working and shops were forced to stop sales as tills went down when the power went out.
NI Electricity said initially 100,000 people were affected by the problem but within half an hour more than half had their power restored.
A spokeswoman for NI Electricity said it had experienced a problem with its high voltage transmission network which affected the power supply in parts of Co Down and Belfast.
Tens of thousands of supplies were hit and some will have noticed a flickering in the system if the power did not go out completely.
Within half an hour of work by engineers, just 40,000 remained without power. But by 3pm on Thursday the fault had been fixed and power was restored to everyone affected.
The cause of the fault is being investigated by NI Electricity.
A spokeswoman apologised for the disruption caused by the power cut and said: "NIE engineers are currently investigating the cause of the fault in Co Down and Belfast area. If your supply is still off, check trips."