Back in March, Tesla’s Elon Musk promised to have a proposed battery storage system at the Hornsdale Wind Farm in South Australia up and running within 100 days, or he’d foot the bill. The project clock started ticking in September and the deadline for the big switch on is December 1, and South Australia’s Premier Jay Weatherill has today confirmed that it’s built and ready to “be energized.”

Weatherill has confirmed that the Tesla Powerpacks have been fully installed on site and connected to the Hornsdale Wind Farm, and are now undergoing testing to make sure that the batteries meet standards set by the Australian Energy Market Operator and the South Australian Government. The Premier is set to join company reps to officially launch the battery storage facility next week.

“While others are just talking, we are delivering our energy plan, making South Australia more self-sufficient, and providing back up power and more affordable energy for South Australians this summer,” said Weatherill. “The world’s largest lithium ion battery will be an important part of our energy mix, and it sends the clearest message that South Australia will be a leader renewable energy with battery storage.”

When it goes live, the 129 MWh Powerpack system will be capable of meeting on-demand power delivery for more than 30,000 homes.