Tesla actually built the world’s biggest battery. Here’s how it works.

Elon Musk and Tesla have made good on an ambitious commitment, and the state of South Australia is now home to the world’s biggest battery. The battery installation is connected to a wind farm (that's what gives it its juice) and the larger grid, and serves as an electricity reservoir for times when power demand peaks or the wind isn't blowing. Musk, a P.T. Barnum-like showman who recently unveiled a new electric truck and next-gen Roadster even while the company's Model 3 deliveries have been slow, had promised that the bold project would be free if they couldn't complete it in time. Now, they have.

It’s fun to imagine an enormous Duracell battery sticking out of the ground, but in reality, the massive installation—it's comparable to a football field's footprint, according to The New York Times— is a network of batteries housed in Tesla-made units called Powerpacks. Tesla isn’t saying precisely how many Powerpacks make up the giant battery, only that they're counted in the hundreds; it packs 100 megawatts of power capable of energizing over 30,000 homes, according to the company.

"The completion of the world’s largest lithium-ion battery in record time shows that a sustainable, effective energy solution is possible," a company spokesperson said in a statement.
That battery is officially known as the Hornsdale Energy Reserve, and it's about 9 miles from Jamestown, South Australia. Its completion comes as summer approaches and Australians will want to crank up the air-conditioning. "South Australia is now leading the world in dispatchable renewable energy, delivered to homes and businesses 24/7," Jay Weatherill, South Australia's premier, said in a statement.

https://www.popsci.com/tesla-building-worlds-biggest-battery-how-it-will-work