Miami Tech & Startup News

Carbon Limit’s cement turns concrete into a carbon capturing sponge

Carbon Limit’s cement turns concrete into a carbon capturing sponge

By Riley Kaminer

In 2021, the process of making cement produced more than 7% of global CO2 emissions. That figure has nearly doubled from 2002 levels and tripled from 1992 levels. Meanwhile, cement’s carbon intensity – the pollution emitted per ton produced – has increased 9.3% from 2015 to 2020.

Cement is at the forefront of the race to decarbonize emissions. Boca Raton-based Carbon Limit is working to accelerate this planet-saving pursuit by developing a more environmentally-friendly cement.

“We’ve made a cement technology that helps lower the carbon footprint of the manufacturing process of concrete between 18 and 36%,” co-founder and CEO Tim Sperry told Refresh Miami

While cement typically comprises around 10% of concrete mix, cement is responsible for 90% of the CO2 emissions of concrete. Concrete is still the main product used in building and infrastructure projects. The recently-passed Infrastructure Law, and the accompanying public sector plans to build at scale, makes this problem even more urgent.

Carbon Limit is still working to determine the exact impact of its cement. But early experiments show that their product reduces the carbon footprint by about 48% over standard cement.

“We turn concrete into a carbon capturing sponge,” explained Sperry. “Our concrete attracts, captures, and stores CO2 directly from the air and into concrete permanently.” There are active materials in Carbon Limit’s cement that act as a magnetic sponge for CO2. Once captured, this CO2 is turned into a solid. 

Because their product captures carbon, the startup will be able to sell carbon credits to companies looking to reduce their CO2 footprint. “The carbon credits are generated when we license our technology to another company and avoid a certain amount of carbon footprint,” said Sperry. The opportunity here is massive, with the global voluntary carbon offsets market size predicted to reach $2.7 billion by 2028, up from $536 million in 2021 at a CAGR of 25.7%.

Carbon Limit co-founder and CEO Tim Sperry

Carbon Limit’s cement, which was developed while the startup took part in a Techstars accelerator with construction conglomerate the Heritage Group last year, is currently ready for commercialization. 

The main customer for Carbon Limit’s product will be cement and concrete manufacturers. In them, Carbon Limit hopes to find a receptive audience, considering the main cement and concrete professional association’s goal to reduce 25% of their carbon footprint industry wide by 2030. But Sperry acknowledged that his company can also provide value to local governments and private sector end users.

Earlier this year, Carbon Limit closed a $1 million pre-seed led by Boca-based Abiding Ventures. Their core team of five full-time employees has recently taken the company through a pivot away from building direct air capture machines.

On top of the Techstars accelerator, Carbon Limit has also gone through FAU Tech Runway. In early June, Carbon Limit was one of just eleven startups to be part of Google for Startups Accelerator: Climate Change. “It’s a really big honor,” said Sperry. “They give us a lot of different resources, mentors, and a lot of programming to help accelerate our businesses but also find ways for us to work with Google.” 

Carbon Limit also continues to work closely with universities, including Perdue and the University of Miami, who will be testing the cement for use in seawalls. 

At top of post: Carbon Limit team, left to right,  Brian Van Bavel (Business Development), Tim Sperry (founder/CEO), Oro Padron (co-founder, CBO), Christina Athina (Marketing).


Riley Kaminer