Thousands of ESB and Eircom workers have been working around the clock to reconnect customers who were cut off by last Wednesday's storm.
20,000 customers remain without power and 25,000 Eircom customers remain cut off from phone lines and broadband.
It said progress will be slow as it has many small outages to fix.
Additional ESB crews were redeployed to help in the areas worst affected, such as Tralee, Newcastle west, Fermoy, Dunmanway, Killarney, Bandon and Waterford.
They are being supported by staff from Northern Ireland's NIE.
ESB Networks has warned the public to be vigilant and not to go near fallen lines as they may still be live.