It’s a rare day when Tesla CEO Elon Musk actually finishes a job before the deadline, but that’s what happened with the massive 100-megawatt battery bank that his company built in South Australia.

The world’s largest lithium-ion battery bank has now been fully installed at Neoen’s Hornsdale Wind Farm and is set to be energized for the first time in a matter of days, South Australia’s state government announced today.

In response to a plea from Australian billionaire Mike Cannon-Brookes, Musk promised in July to get the array of Powerpacks installed within 100 days of signing a grid connection agreement, or else the job would be done for free.

Musk had some wiggle room: By the time the agreement was actually signed on Sept. 29, Tesla had already completed half the project. Nevertheless, he was taking a risk on a project that’s thought to cost tens of millions of dollars.

Tonight Musk tweeted his congratulations to the team:

Congratulations to the Tesla crew and South Australian authorities who worked so hard to get this manufactured and installed in record time! https://t.co/M2zKXlIVn3 — Elon Musk (@elonmusk) November 23, 2017

The battery bank will undergo a round of testing to ensure the system is fully optimized and meets the requirement for connection to South Australia’s power grid, according to a statement from the office of Premier Jay Weatherill. Throughout the testing period, the Powerpack system will be providing system security services to South Australia.

State authorities selected Tesla system in a competitive bidding process to beef up electrical storage capacity for the transition from coal-fired plants to wind and solar power. Last year, storm damage to South Australia’s electrical grid caused a cascade of failures, leading to a massive blackout that left 1.7 million residents without power for as long as two weeks.

Weatherill and representatives from the French energy company Neoen, Tesla and Consolidated Power Projects are due to officially launch the battery system next week.

“While others are just talking, we are delivering our energy plan, making South Australia more self-sufficient, and providing backup power and more affordable energy for South Australians this summer,” Weatherill said in today’s statement.

“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 [in] renewable energy with battery storage,” he said. “An enormous amount of work has gone in to delivering this project in such a short time, and I look forward to visiting Jamestown next week to personally thank those who have worked on this project.”

Musk typically stretches the deadlines for his projects, ranging from the production ramp-up for the Tesla Model 3 electric vehicle to the maiden launch for SpaceX’s Falcon Heavy Rocket. But even if Musk misses a deadline, he persists nevertheless.

“People should take a look at my track record and realize that I always come through in the end,” Musk told me back in 2010. “It may take more time than I expected, but I’ll always come through.”