Essential Energy's David Crough said crews responded immediately when the power shut down in Gunnedah at 7.20am, leaving 3257 homes and businesses without power, and the town's traffic lights out of action during peak traffic time.

Mr Crough said the power network switched itself off after sensing a problem at the Gunnedah zone substation.

“Our Gunnedah-based crews responded immediately and quickly ascertained that a bird had caused the unplanned power interruption,” Mr Crough said.

The power was back on at 8.57am after local Essential Energy crews consulted with specialised zone substation technicians.

“We thank the Gunnedah community for their understanding as we worked as quickly and safely as possible to restore power,” Mr Crough said.

Zone substations convert high voltage power to a level which can be distributed throughout the community for use in homes and businesses.