ESB Crews from Co Donegal have spent the night in the North trying to help restore broken power lines as 40,000 homes were plunged into darkness.
Northern Ireland Electricity has launched an investigation after a blackout left around 200,000 homes and businesses temporarily without power in the Belfast area on Friday night.
It is the first time in decades that a a power cut on such a huge scale had happened in Belfast.
The power cut, which lasted between 10-20 minutes in parts of the city, was caused by a major fault on the transmission network.
Electricity was later restored to all customers affected by that fault.
Last night there were reports of 10ft snow drifts in Mallusk, around six miles outside Belfast.
Around 44,000 homes and businesses remained without electricity across Northern Ireland after storm-force winds of up to 55mph and heavy snow damaged the electricity network.
At one point 100,000 homes were without power across the six counties.