We went inside Tesla’s Gigafactory. Here’s what it looked like

Elon Musk has called Tesla’s Gigafactory the “machine that builds the machine.”

The $4.5 billion factory, located outside Reno, Nevada, is where Tesla and Panasonic, its principal partner, produce battery packs for Tesla’s Model 3 sedan, along with energy storage products and more.

CNBC went inside the Gigafactory to view the production process and understand how the company’s first fully built factory will serve as the model for what eventually could be a dozen massive Tesla factories globally.

“In order to transition the world to sustainable energy, we really needed to build this big, build this boldly and really build as many battery cells as we possibly could to really accelerate this transition,” Chris Lister, Tesla’s vice president for operations, told CNBC.

Only about 30% of the factory is currently built out, but upon completion it could be the world’s largest building by footprint.

The partnership between Tesla and Panasonic has come under strain recently.

Last month, Tesla, denied reports that it was placing Gigafactory expansion plans on hold. Meanwhile, Musk claimed Panasonic was unable to meet production goals for battery cell output.

Tesla, meanwhile, said U.S. orders for Model 3 had outpaced its available output in the first quarter.

The Gigafactory, which is open around the clock, currently has 7,000 employees.

Yet humans were few and far between during CNBC’s portion of the tour as automation was highly apparent, with one section of the facility boasting a 90% automated process, according to Lister.

Still, he said the company has had to back off on automation in some cases, in favor of human labor.

“It’s easier to, you know, grab things like hoses out of midair and attach them together as a person looking at those, as opposed to trying to get a robot to do that,” he said.

Meanwhile, Tesla’s $2 billion dollar Gigafactory in Shanghai, or Gigafactory 3, which broke ground this year, is expected to produce Tesla’s Model 3 using a complete vehicle production line before the end of the year.

Lister said Tesla is using what it’s learned from its Nevada facility toward its upcoming China factory and hoping to use the original Gigafactory as an operational model for all future facilities.

“So many people have invested so much of their lives into making this successful,” Lister said. “It really is a competitive advantage, but it is also so important in accelerating the advent of sustainable transport.”