More than 800 contractors have descended on Bayswater power station near Muswellbrook as part of an 85-day maintenance outage designed to ensure the coal generator is in peak condition over the summer months.
The $114 million Unit Two overhaul will see maintenance conducted on everything from turbines through to the electrical switchboards and the boiler.
Unit Two is one of four 685 megawatt hour generators at the plant that are overhauled every four years.
"Extensive planning and preparation have gone into ensuring that this outage will be completed safely and that it will set Bayswater up to continue to deliver power when our state needs it most," Bayswater general manager Len McLachlan said.
"It's a significant investment that will also provide a platform for AGL to deliver our pipeline of renewable energy projects as quickly as possible."
"Importantly, it will also provide a major boost to our local businesses as they service the needs of the 800 contract workers involved in the outage."
The plant, which supplies about 20 per cent of the state's energy requirements, is scheduled to continue operating until as late as 2033.
Work is also proceeding on the decommissioning of the adjacent Liddell site.
Decommissioning works are complete and early demolition works underway.
The works have included repurposing more than 45 kilometres of conveyor belt, 800,000 litres of transformer oil and more than 150,000 litres of turbine oil.
The former power station contains about 70,000 tonnes of metal, including 3000 tonnes of highly valuable non-ferrous metals such as copper and chromium. By comparison, the Sydney Harbour Bridge contains only 50,000 tonnes of steel.
There's also about 120,000 tonnes of concrete that will be crushed and recycled.
The money made from recycling materials will help offset the $225 million that AGL has budgeted for decommissioning and demolition works.
A timeline for demolition of major infrastructure, 168 metre tall stacks, will be finalised once regulatory approval is received.
Early construction works are also underway on the 500 megawatt two-hour Liddell grid-scale battery.
Battery cubes have been delivered and installation is scheduled for January 2025.
Fluence has been selected as the preferred engineering, procurement and construction provider for the battery, which has an expected life of 20 years.
It is scheduled to start operations in mid-2026.
The battery is part of a clean energy hub that will host an estimated $1 billion-plus portfolio of industries including agriculture, clean energy and firming technologies, composting, coal ash recycling, green metals and advanced manufacturing.
It is expected that the hub could eventually employ more than 1000 people and serve as a major catalyst for future economic growth in the region.
"This is not just about the transition of a single site, it is the transition of the entire region from a very coal intensive region into a renewable space," AGL chief operating officer Markus Brokhof said previously.
"It will require a huge effort, not just from AGL but from all of the players. Where you have examples of successful transition overseas it is always the result of a collective effort."
