The skyline of Wallerawang, dominated by the chimneys of its former coal-fired power station, is about to look very different.

The generator has been defunct since 2014 but a new company has taken over the site near Lithgow in central-western NSW to decommission the plant and turn it into a multi-purpose industrial area and renewable energy battery. 

Greenspot was established in 2020 with the aim of rescuing stranded assets from the fossil fuel industry. 

Chief executive Brett Hawkins said it was the new company's flagship project.

"Our objective in undertaking this project is to retain as much infrastructure as possible and to repurpose that infrastructure," he said. 

The company plans to keep the old turbine hall and the cooling tower. 

Two of the three chimneys will be knocked down, but the shortest one will be retained because it was part of the original coal generator built in the 1950s.

"So a very strong legacy and we're looking to preserve that legacy wherever possible."

The power station itself covers 90 hectares, but the entire site is more than 450 hectares and includes pine plantations, a substation and Lake Wallace.

Greenspot hopes to develop the entire site into a multi-purpose area for industry, agriculture and recreation once the clean-up is finished.

From burning coal to renewable battery

Greenspot's first goal for the site is to build a large-scale battery to assist the state's transition to renewable energy. 

The Wallerawang 9 Battery Project would have a capacity of 500 megawatts and 1,000 megawatt hours of storage. 

That means it could discharge renewable energy at full capacity for two hours before it needed to be recharged.

The executive of business development, Sam Magee, said it was the perfect site to build a battery.

Mr Magee said the battery would cost less than $500 million and could be ready as soon as 2023.

French company Neoen, which operated the big battery in South Australia, is proposing to build a similar sized battery nearby. 

"There's projected huge demand for additional batteries in the system over the next few years to support the introduction of renewables and the exit of old coal- and gas-fired power stations," Mr Magee said.

'First-of-its-kind' project

Working on a site that's been burning coal for almost 70 years is not without its challenges. 

The contractors in charge, Liberty Industrial, have worked on several old power stations. 

Project director Simon Gill said this was a "first-of-its-kind" project because it was not a complete demolition.

"Often these big industrial sites can have limited uses because of what they were and it can put off a lot of prospective developers," he said.

"I think it's a great initiative, particularly for regional areas to have an opportunity to repurpose the site and bring some employment back to these areas."

The site is contaminated with oil, asbestos and coal dust from decades of use. 

Mr Gill said the clean-up and decommissioning would cost "tens of millions of dollars" and take around 18 months.

He said the asbestos would be stored in a special cell on site and would not be removed.