With a number of fires still burning and extreme conditions forecast over coming days, Essential Energy has warned more customers could be affected in areas where the blazes are threatening power supplies.

Brendon Neyland, Essential Energy's acting general manager customer & network services, said the scale of what is ahead is significant.

"We are anticipating emergency response will continue for some days under challenging conditions. We are hoping conditions ease today to allow safe access to inspect network damage before the anticipated worsening today and Tuesday," he said.

"Tuesday's fire conditions are forecast to be extreme so the situation could deteriorate, resulting in further network damage and limiting our ability to gain safe access to impacted areas and restore power."

As of 12pm on Sunday, November 10, there were 7,025 customers without power.

"We will be mobilising up to 300 staff from across our network to assist in restoration efforts. We've established Essential Energy response hubs in Taree, Kempsey, Port Macquarie, Grafton and Nambucca with support from teams across our organisation to safely restore the power to impacted communities," he said.

Customers in the local government areas of Mid Coast, Port Macquarie-Hastings, Kempsey, Armidale, Nambucca, Bellingen, Clarence Valley and Ballina are all impacted by outages as the fires damaged parts of Essential Energy's electricity distribution network.

Initial indications are that in excess of 400 poles have been destroyed by the fires, and this number is likely to increase as crews can safely assess impacted areas.

Essential Energy crews have restored electricity to a number of homes and businesses over the last 48 hours but is emphasising that customers should be prepared for their power to go out before the fire hits their property.