Tesla has struck a deal with the state government of South Australia to install 50,000 solar-power systems on homes, at no cost to residents.

This will the world’s largest virtual power plant, slashing household power bills in the process.

South Australia is already home to world’s biggest battery in an Elon Musk-driven project to provide electricity for more than 30,000 homes.

“My government has already delivered the world’s biggest battery, now we will deliver the world’s largest virtual power plant,” state Premier Jay Weatherill said in a statement.

“At key moments, the virtual power plant could provide as much capacity as a large gas turbine or coal power plant,” the company added.