Twenty-three thousand properties in north Lancashire will have their power supplies switched back to the National Grid today.
More than 70 generators have been used to provide power while engineers fixed the main Lancaster substation that was damaged by flooding in the aftermath of Storm Desmond.
Electricity North West says properties will lose power for up to 30 minutes when they are reconnected to the National Grid between 5pm and midnight.
In Cumbria around 1,000 properties remain without power due to flooding. Engineers will carry out door-to-door safety checks on equipment before being able to safely restore power.