A solar farm at Murray Bridge North has been completed and begun pumping power into the grid.
Terregra Renewables' five-megawatt Mobilong Solar Farm was switched on earlier this month.
Its 15,600 photovoltaic modules and two inverters are expected to last for 30 years.
The company already has an agreement in place to sell all the power they produce.
At the peak of construction, company director Graham Pearson said more than 50 people had been working at the site, including plenty of locals.
"From the start, we wanted to develop high-quality projects, be good neighbours and bring positive benefits to the local community," he said.
"It was pleasing to see so many high-quality local businesses involved in the project.
"This will continue during the operation phase, with local tradespeople already contracted to provide maintenance services for the next few years."
The Mobilong facility is part of a network of small solar farms Terregra has proposed across Australia.
The project is the second to reach completion in the Murraylands this year.
The first stage of Vena Energy's solar plant at Tailem Bend, with a capacity of 95MW, opened in May.