Solar startup Heliogen used mirrors, arrayed using artificial intelligence, to concentrate sunlight and generate temperatures above 1,000 degrees Celsius. At that temperature, fossil fuels can be replaced in critical industrial processes, including the production of cement, steel, and petrochemicals to dramatically reduce greenhouse gas emissions.

Heliogen, whose backers include Bill Gates, said it was the first time the solar technology had been used commercially.

Cement production accounts for 7% of global carbon dioxide emissions, according to the International Energy Agency.

“The world has a limited window to dramatically reduce greenhouse gas emissions,” Heliogen chief executive officer Bill Gross said. “We’ve made great strides in deploying clean energy in our electricity system. But electricity accounts for less than a quarter of global energy demand.”

Heliogen said earlier systems using concentrated solar energy could produce heat up to 565 degrees Celsius, which is not hot enough for some industrial processes. Gross said this system achieved the breakthrough the first day the plant was turned on.

“I’m pleased to have been an early backer of Bill Gross’s novel solar concentration technology,” Bill Gates, the billionaire Microsoft founder, said in a statement. “Its capacity to achieve the high temperatures required for these processes is a promising development in the quest to one day replace fossil fuel.” Gates said industrial processes like those used to make cement and steel account for more than a fifth of all carbon dioxide emissions.

Other Heliogen investors include Neotribe and Nant Capital. Patrick Soon-Shiong, the chairman of NantWorks, and Swaroop Kolluri, the founder and managing director of Neotribe, are on Heliogen’s board of directors. Its strategic partner is Parsons Corporation.

Heliogen said the technology could be used some day to generate clean hydrogen that could in turn be used as fuel.

“If you can make hydrogen that’s green, that’s a gamechanger,” Gross said. “Long term, we want to be the green hydrogen company.”