Entrepreneur Elon Musk has finalised a network agreement to connect his 100-megawatt lithium-ion battery to South Australia's energy grid, starting the clock ticking on his promise to build it within 100 days or it's free.
Mr Musk visited Jamestown, in SA's mid-north, on Friday where construction of what will become the world's largest battery storage facility is already about 50 per cent complete.
The Tesla boss said the South Australian project was an example of how to replace fossil fuels with renewables.
"This is a great example to the rest of the world of what can be done," he said.
"When this is done in just few months, it will be the largest battery installation by a factor of three."
The SA battery will be paired to a neighbouring Neoen Hornsdale Wind Farm to bring added reliability and stability to the state's power supplies.
The agreement has been approved by the Australian Energy Market Operator and signed by transmission company Electranet.
"Tesla and Neoen now have 100 days to complete the largest lithium-ion battery storage project in the world," Mr Musk's company said in a statement.
"It will help solve power outages, reduce intermittencies and manage summertime peak load to support the reliability of South Australia's electrical infrastructure."
The Tesla powerpacks which make up the facility were manufactured at the company's Gigafactory in Sparks, Nevada and were used to power the event at Jamestown.
The South Australian government received more than 90 competitive bids for the battery project which forms part of its $550 million energy plan.
It's thought to be costing taxpayers about $50 million.
Other elements of the energy plan include installing emergency generators at two sites in Adelaide, a push for more gas-fired power generation and a solar-thermal power plant near Port Augusta.
It was prompted by a series of power issues, including a statewide blackout when a freak storm brought down transmission lines a year ago and another event last summer when heavy demand and a lack of electricity flowing through the interconnector with Victoria forced AEMO to cut services to thousands of properties.
The deal to build the battery was signed about two months ago and Mr Musk said the remarkable progress was a credit to the Tesla team who had worked "night and day".
"It's not done yet, it's roughly at the 50-megawatt level. But to have that done in two months is really incredible," he said.
"You can't remodel your kitchen typically in that period."
South Australian Premier Jay Weatherill said the project reaffirmed South Australia's standing as the renewable capital of Australia.
