On Friday, Elon Musk – the Chief Executive Officer of Tesla – announced at a Jamestown, South Australia event that the U.S.-based electric car making company was halfway done in installing a 100MW/129MWh utility-grade battery bank. The battery installation was done near the site of the 100MW Hornsdale Wind Farm.

Why was the 100-days countdown of Tesla taking so much time to start?

When the mentioned battery bank is fully build, it will become the largest grid-tied system worldwide. The largest grid-tied system in the world currently is a 30MW/120MWh facility that was built in Southern California by AES Energy Storage. The project was born from an online (social networking site ‘Twitter’– to be exact) bet between SpaceX and Tesla CEO Elon Musk and Australian software billionaire Mike Cannon-Brookes.

Cannon-Brookes was doubting the time and speed that Tesla claimed it would take to install grid tied batteries, and in response, the Tesla CEO had promised to deliver a system to South Australia in 100 days or the work would all be for free. Australia is a state that has suffered tiring blackouts in recent summers. However, this “100 days or it’s free” promise of the Tesla CEO did not include any time negotiating contracts and the automaker went through a competitive bidding process with the state of South Australia after the bet.

This bidding process was for the access to an Aus$150 million ($115 million) renewable energy fund to cover the expense of the batteries. On Twitter earlier this year, the SpaceX CEO gave estimates which suggested that a 129MWh system would cost $32.35 million before labor and taxes.

Tesla starts its 100-days countdown for battery installation

The U.S.-based automaker has won the bidding round and has partnered with Neoen, a France-based company that is the owner of the Hornsdale Wind Farm in the mid-north region of South Australia. Later, the Tesla CEO commented that if the EV maker missed its 100-day deadline, it could lose around $50 million or more.

The automaker announced this Friday the start of its 100-days countdown, which was initiated after the project was approved by the Australian Energy Market Operator (AEMO). On Friday, Tesla CEO said that the automaker was already halfway done with building the battery bank and installing the batteries, according to the Australian Broadcasting Corporation (ABC). The batteries are being made in Sparks, Nevada at the Tesla Gigafactory.

The report by ABC noted that Jay Weatherill, the South Australian Premier, was also in attendance at the Friday night party of Tesla and he had told the audience, “There were lots of people that were making jokes about South Australia and making fun of our leadership in renewable energy. Well today they’re laughing out of the other side of their face.”