Elon Musk's Tesla built the Powerpack system, which can provide electricity for more than 30,000 homes, to ease South Australia's energy woes after the state was hit with a total blackout in 2016 following an "unprecedented" storm.
The maverick billionaire earlier this year offered on Twitter to build the battery farm, and completed it last week to narrowly beat his self-imposed deadline of having it ready in 100 days.
"South Australia is now leading the world in dispatchable renewable energy, delivered to homes and businesses 24/7," state Premier Jay Weatherill said Friday at the launch to coincide with the first day of the summer season.
The 100 MW/129 MWh battery -- in the rural town of Jamestown north of Adelaide and connected to a wind farm operated by French energy firm Neoen -- supplied 70MW of stored energy Thursday, the Australian Energy Market Operator (AEMO) said.
It is expected to help tackle power shortages, reduce intermittencies and address peak demands in summer, when most of the country experiences its highest energy usage.
Tesla said it was hopeful that the project would provide a model for future deployments around the world, adding in a statement Friday that its fast completion "shows that a sustainable, effective energy solution is possible".
Last summer, extreme hot weather as well as storms saw blackouts hit some regions of Australia.
The AEMO switched on closed gas-fired power stations to provide extra power to Australia's east coast this season.
Although Australia is one of the world's largest producers of coal and gas, the South Australian blackout raised questions about its energy security.
Several aging coal-fired power plants have been closed, while strong demand for gas exports and a rise in onshore gas drilling bans have fuelled concerns of a looming domestic energy shortage in the next few years.
