No doubt that Rick Fox has had plenty of emotional moments in his life. There was the birth of his children, of course, and as a member of the Los Angeles Lakers in the early 2000s, he won three NBA championships. But last week, it’s clear that his third act — that of a startup founder — is becoming one of those moments.
“I’ve been a part of a lot of amazing journeys and industries, from entertainment to movies and TV. I’ve been on sets with Oscar-winning actors and directors, and I’ve been on championship NBA teams. There’s been nothing more rewarding for me in my life than to be a part of this team where we’re leaving something behind,” Fox told TechCrunch+.
Fox’s new challenge isn’t just building Partanna, a startup, but one that can make a dent in climate change. For him, it’s personal. Like many of us, Fox was sitting at home early in the pandemic mulling the challenges that were facing the world. The Bahamas, where he grew up and now lives, wasn’t just in the midst of a pandemic. It was still reeling from the destruction wrought by Hurricane Dorian in 2019.
“It got me to a point of thinking about a bigger crisis, which was one that we were facing at home in the Bahamas, which is the consistent impact of the climate and the storms that were happening on a yearly basis at a different level than what I grew up with.”
Then he got a call from his manager, who had been displaced by the Woolsey Fires that swept through Malibu in 2018. In the recovery efforts, she ran into Sam Marshall, an architect who had been working on a new formulation for concrete for the last several years.
“She called me up one day and she said, ‘Hey, you have to meet this gentleman. He’s been working on concrete that acts like a tree,’” Fox recalled. “And I’ll never forget that statement, because I had just stepped out of the shower and I was drying off, and I’m thinking to myself concrete that acts like a tree — how does that work? But then I also thought, if it does work, then it’s going to be on the forefront of changing how we build in the world.”
Marshall had been working for years with other concrete experts, and the time was right to start a company. The two founded Partanna in 2021, and now the company is announcing $12 million in pre-seed funding from Cherubic Ventures, TechCrunch+ has exclusively learned. The company is valued at $190 million post-money, according to PitchBook data.
There are two components that are key to Partanna’s concrete. One is a waste product from steel production known as slag. The world produces anywhere from 190 million to 280 million metric tons of steel slag every year, according to the U.S. Geological Survey. The other is brine from desalination plants, of which there are more than 16,000 worldwide.
Those two components replace Portland cement, the key binding agent in most concrete. (Quick terminology aside: Most people use cement and concrete interchangeably, but they’re different. Cement is a binding agent that holds the aggregate, the small stones, together. Concrete is what results when cement and aggregate are mixed together.)
Portland cement is made by heating limestone and other minerals to extraordinary temperatures by burning fossil fuels, usually coal. Massive amounts of carbon dioxide result both from the fossil fuel combustion and the resulting chemical reaction. The cement industry is responsible for at least 8% of the world’s carbon pollution.
Partanna’s concrete uses magnesium and slag cement as a binder. Apart from the initial energy required to make both — magnesium from desalination plants, slag from steel mills — the startup’s cement doesn’t require much additional energy to prepare it. Plus, because of the chemical reactions that occur when it cures, it removes carbon dioxide from the atmosphere. Regular cement does this to some extent, though not as much. “We absorb CO2 100 times faster than what a regular cement block would,” Fox said. As a result, Partanna’s concrete is carbon negative.
Partanna is also selling carbon credits that result from the production of its concrete. A single block of its concrete avoids or removes 14.3 kg (31.4 lbs) of carbon dioxide, with almost 80% of that from the CO2 it absorbs over its lifetime. One 1,250 square-foot home would remove almost 130 metric tons of CO2 and avoid another 54 metric tons.
To Fox, that timeline creates unique opportunities. “What happens if we include individuals that are actually doing the work and you’re carving out those carbon credits for the labor?” he said. “You can also see how then those carbon credits can be used and shared amongst everyone involved, including the end user.”
For island nations like the Bahamas, that value proposition is appealing. The country has relied on concrete as a building material that’s durable enough to withstand hurricanes, but it’s also aware that concrete threatens its very existence through sea level rise. Partanna’s blocks eliminate the carbon pollution and tackle the waste from desalination plants. That’s partly why the Bahamian government has a memorandum of understanding with Partanna for the startup to supply concrete for 1,000 homes over the next three years.
Another part of the world that’s rich with desalination plants, the Middle East, is also taking note. At COP27, the global climate meeting held in Egypt last year, Fox signed an MOU with Red Sea Global, a real estate developer owned by the Saudi Public Investment Fund.
The demand, Fox said, has caught the company off guard. “Our initial thought in terms of what we thought we would raise is now stretching,” he said. The company is planning a substantial Series A.
Even with a large Series A factored in, Partanna’s output will be a relative drop in the bucket. But if the company can keep up the pace, it stands to put a significant dent in the carbon footprint of the concrete industry. That has the potential to turn a large fraction of the world’s buildings into carbon sponges. For Fox, that would be the dream.
“We’ve talked about delinking pollution from development, and that to me sounded like a worthy enough challenge.”