The world's biggest lithium ion battery, built by Tesla, has been switched on to help solve South Australia's chronic power problems.
Tesla Inc switched on the world's biggest lithium ion battery in time to feed South Australia's shaky power grid for the first day of summer.
The move fufills a promise by the firm's founder Elon Musk to build it in 100 days or give it away for free.
Tesla won a bid in July to build the 129-megawatt hour battery for the state of South Australia, which has expanded in wind power far quicker than the rest of the country and suffered a string of blackouts over the past 18 months.
Supporters of the project say it will help stabilise the grid and provide "dispatchable renewable energy" in a region that now gets more than 40 percent of its electricity from wind energy.
But critics have described it as a "Hollywood solution" in a country that still relies on fossil fuels, mainly coal, for two-thirds of its electricity.