Elon Musk has finished building the world's biggest battery in less than 100 days (South Australia)

Elon Musk looks to have delivered on his promise to build the biggest lithium ion battery in the world in an effort to help South Australia with its crippling energy problems. “100 days from contract signature or it’s free,” Musk tweeted at the time, in a deal initially negotiated over Twitter. Musk is well ahead of schedule (a rarity for Tesla!), with the 100MW battery set to be energised and tested in the coming days, according to a press release from the local state government.

Tesla Powerpacks have been installed and connected at Neoen's Hornsdale windfarm, north of Adelaide, and battery tests will be run to ensure local regulatory requirements are met before it begins operating on December 1st. South Australia suffered a state wide blackout last September, which sparked a highly politicized national debate about energy security. The Australian Government blamed the failure of renewable energy to cover usage. Musk's battery farm stores huge amounts of energy from renewable sources like wind and solar, and funnels it out to the grid when usage is high.

Tesla will get the system installed and working 100 days from contract signature or it is free. That serious enough for you?

— Elon Musk (@elonmusk) March 10, 2017


Musk made his promise in March on Twitter and the 100-day countdown started at the end of September after the company inked a deal with the South Australian government. Musk essentially delivered his promise in about two months, well short of the self-imposed 100-day deadline. The battery is estimated to cost at least $50 million.

"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 [sic] renewable energy with battery storage," South Australian Premier Jay Weatherill said in a statement. "An enormous amount of work has gone in to delivering this project in such a short time."

Elon Musk will get paid for building the world's largest lithium-ion battery in South Australia, as the 100-megawatt project is about to begin testing ahead of a December 1 deadline to complete building it or make it free.

State premier Jay Weatherill announced on Thursday that regulatory testing at the site — which is paired with the French energy business Neoen's Hornsdale wind farm, 230 kilometres north of Australia's capital, Adelaide — would begin within days.

When fully charged, the battery, Tesla's Powerpack, is expected to hold enough power for 8,000 homes for 24 hours, or more than 30,000 houses for an hour during a blackout.

The project is part of a $550 million plan by the state to guarantee energy supply following a statewide blackout last year that turned into a national political debate over energy security and costs. A 250-megawatt gas-fired generator, expected to cost $360 million, is also due to come online this summer to provide extra power.

The battery is the result of a Twitter bet between the Tesla founder and Atlassian's Mike Cannon-Brookes in March that he would supply the battery within 100 days or it was free. The clock began ticking when Musk visited Adelaide in September to sign off on the deal — though work was already underway on the plant after the government gave the contract to Musk in July.


Musk had said that if he failed to meet the deadline, it would have cost him "probably $50 million or more."

The Tesla plant will be called upon during periods of "load shedding," when excess demand would otherwise result in blackouts.

Weatherill said that the battery was now complete and that the testing would ensure it is optimised and meets energy market regulatory requirements.

"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 into 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."

Tesla has completed construction of a massive 100 megawatt, 129 MWh battery installation in South Australia. The new facility boasts the largest megawatt rating for any grid-connected battery installation in the world.

The project was completed less than two months after the contract was signed on September 29, putting it ahead of schedule. Musk had promised Australian authorities that he would complete the project in 100 days or the project would be free. Musk has said it would cost Tesla "$50 million or more" if the company failed to meet the deadline.

"Congratulations to the Tesla crew and South Australian authorities who worked so hard to get this manufactured and installed in record time!" Musk tweeted late on Wednesday night (Thursday in Australia).

The state of South Australia saw a need to beef up its electricity infrastructure after a September 2016 storm caused a state-wide blackout. State officials wanted to ensure that didn't happen again, and they wanted to find a solution that made use of renewable energy.

The Hornsdale Wind Farm near Jamestown, South Australia, produces 315 megawatts of power, but like any wind farm it's not a steady source of power. So Tesla's batteries will charge up during periods when the wind farm is producing excess energy, then supply extra power to the grid during periods of peak demand.

Tesla's involvement in the project originated from a March Twitter conversation between Musk and Australian billionaire software entrepreneur Mike Cannon-Brookes. Musk said that if he got the contract, "Tesla will get the system installed and working 100 days from contract signature or it is free."

Tesla won a competitive bidding process in July and signed the contract in September. The system needs to undergo a few days of testing and is expected to be put into operation in early December.

Tesla is normally thought of as a car company, but this announcement underscores the fact that Tesla is really a battery company. Tesla has built a massive battery factory in Nevada and needs to make sure it can sell the massive number of batteries that factory will be producing in the coming years.

Of course most of those batteries are supposed to go into Tesla's cars. But developing a side business in battery packs for use by residential customers and electric utilities helps to diversify Tesla's business. If the car business hits unexpected snags—as it has with the Model 3 launch in recent months—Tesla can sell the extra batteries for non-car uses.

And it's going to take a lot more installations like the one in South Australia if the world is going to ultimately wean itself off of fossil fuels. Wind and solar energy are becoming increasingly affordable, but both types of power produce energy intermittently. Huge battery installations ensuring that utilities can supply households with electricity around the clock—even at times when the sun isn't shining and there isn't much wind.