NATIONWIDE — What do Buick, Cadillac, Chevrolet and GMC have in common? Not only are they made by General Motors, they have all had a sizeable presence at the annual Los Angeles Auto Show.

But this year, only Chevrolet will be presenting cars, as the 113-year-old automaker focuses its attention on a major milestone in Detroit. On Wednesday, General Motors officially opened Factory ZERO — an assembly plant that will only build electric vehicles as it shifts to a zero-emissions future.

“We will be the first plant in North America with an on-site battery assembly area that will feed directly to the line,” Factory ZERO Assistant Plant Director Cathy Staelgraeve told Spectrum News, adding that the portion of the plant that will be used to assemble batteries is still under construction.

Indeed, only a third of the 4.5-million-square-foot space is operational as of Wednesday’s grand opening. About 650 of 2,200 planned employees currently work there, though pre-production has already begun on the highly anticipated GMC Hummer EV pickup that will be delivered to customers by the end of the year.

Following the $113,000, 1,000-horsepower Hummer EV Edition 1, the plant will make the GMC  Hummer EV SUV, a battery-electric version of the Chevrolet Silverado pickup truck and the Cruise Origin autonomous vehicle.

The Detroit-Hamtramck assembly plant that is now known as Factory ZERO had, most recently, built Chevy Impalas. But over the past 22 months, it’s been completely gutted and retooled with a $2.2 billion investment to help GM achieve its goal of completely phasing out gas-powered vehicles by 2035.

The hope is that Factory Zero will help it launch future EVs more quickly, with better quality and for less money.

“The body shop is essentially the same. The paint shop is essentially the same,” Staelgraeve said, adding that about 80% of an EV’s assembly process is the same as a gas-powered vehicle. “That’s what gives us a competitive advantage. Our people have been building cars and trucks their whole careers.”

In a statement, the company said “Factory ZERO serves as a model for transitions that will take place at other factories around the world in the coming years.”

All of the EVs built at Factory Zero will use the Ultium Platform GM Chief Executive Mary Barra announced earlier this year at the Consumer Electronics Show. Ultium is a new battery technology the company developed that can produce up to 450 miles of range on a charge at nearly 40% less cost and 25% less weight than its current EV batteries.

As part of that announcement, Barra said the company planned to bring 30 new EVs to market within the next five years, including the battery-electric Cadillac Lyriq sedan and the all-new “ultra-luxury” Cadillac Celestiq (billed as “a new future for integration of technology and the senses” with customizable roof glass tinting for each passenger).