Thousands of solar panels will be installed on top of the old Holden car assembly plant in Adelaide to supply power to the site's new tenants.
Renewable energy company Carnegie also plans to link the panels to battery storage to help provide cheaper and more reliable electricity.
Carnegie managing director Michael Ottaviano said the $8.3 million micro-grid to be installed on the former car plant was one of the biggest of its type in the country.
"What it will do is give energy to the current and future tenants that is cleaner, more secure and cheaper than what they can currently access from the grid," he told reporters on Wednesday.
Mr Ottaviano said the company would cover about 20 per cent of the plant's roof space to produce about three megawatts of power panels and would also install about two megawatts of battery storage.
But he said there was no reason the plant couldn't be expanded to cover the entire roof space.
"It's a way of looking at what formerly would have been just a roof and turning it into an energy production asset," he said.
South Australian Energy Minister Tom Koutsantonis said the project was symbolic of the broader transition of the state economy to high-tech industries.
"Jobs are our number one priority and this solar battery project by Carnegie is part of a wave of new investment," he said.
The micro-grid is expected to be operating by December this year and is being supported by a $3 million SA government grant.
