I shut down my entire career that was in Hollywood to pursue and create [climate] solutions,” Fox tells The Verge. “I had to move around the industry that was new to me and meet people that were looking at me like, ‘What the hell are you doing in concrete?’””“What the hell are you doing in concrete?””Concrete just happens to be a major source of the greenhouse gas emissions causing more intense storms, wildfires, and other catastrophes through climate change. The culprit is actually cement, a key ingredient in concrete that alone is responsible for more than 8 percent of carbon dioxide emissions globally.“My entry into the world of concrete was one out of just sheer survival and the need to innovate in my own home country,” Fox says. Hurricane Dorian struck the Bahamas in 2019, wrecking 75 percent of homes on the worst hit island of Abaco and displacing thousands of people. Fox was in Los Angeles at the time. “The closest thing I could do was race to CNN to scream from the rooftops that we needed to do something better,” he says.Soon after, he met California-based architect Sam Marshall, whose home had sustained damage in the 2018 Woolsey fire, one of the most destructive blazes in the state’s history. Marshall had already “caught lightning in a bottle,” according to Fox. Working with material scientists, they’d developed a way to make concrete without using carbon-intensive cement. Together, they co-founded Partanna.The pair are pretty tight-lipped around the process, but the main ingredients are brine from desalination plants and a byproduct of steel production called slag. By getting rid of cement as an ingredient, Partanna can avoid the carbon dioxide emissions that come with it. Making cement produces a lot of climate pollution because it has to be heated to high temperatures in a kiln and because it triggers a chemical reaction that releases additional CO2 from limestone.Partanna says its mixture can cure at ambient temperatures, so it doesn’t have to use as much energy. It also says binder ingredients in the mixture absorb CO2 from the air and trap it in the material. In a home or building, the material continues to pull in CO2. Even if that structure is demolished, the material holds onto the CO2 and can be reused as an aggregate to make more of the alternative concrete.That’s how the startup and can call its material and the newly constructed home “carbon negative.” The 1,250-square-foot structure is supposed to have captured as much CO2 as 5,200 mature trees a year.