AGL Chief Operating Officer, Markus Brokhof said the summer months are fast approaching, and these works are critical to ensure we maintain safe operations while providing reliable power to our customers.

"With four separate generating units, we are able to take a single unit offline for maintenance without any impact on the operation or output from the rest of the station," Mr Brokhof said.

"These current works along with the $22 million we recently spent on maintenance works at Bayswater are not just important to our site operations, but also in supporting our local community and economy.

"We know regional communities, like the Upper Hunter have been heavily impacted by severe drought, bushfires and more recently COVID-19 and as such local businesses are keen to see people return to this beautiful region.

"The works will be finished in early December and throughout this outage, we expect to have around 400 contractors on site which will play an important role in helping drive our local economy and businesses."

AGL is continuing its closure and transition plans for Liddell and this will be the last major outage at the site before it is retired in April 2023.

The scope of work will include process safety works, boiler tube inspection repair and replacement, feed water heater maintenance, air heater and condenser repairs, a low-pressure turbine cover lift and inspections of electrical controls and protection systems.

During the COVID-19 pandemic, AGL has implemented important management controls across the site including social distancing, hygiene controls, and temperature screening at security gates. AGL site teams and contractors will be focussed on personal safety and the safety of their workmates during the outage period.