After water, concrete is the most commonly used material on earth. But traditional methods of producing its main ingredient, cement, are not kind to the planet.
The global cement production industry accounts for approximately 8% of annual carbon emissions. It is usually made by heating limestone, a carbonate rock, using a fossil fuel kiln. It’s a double whammy of CO2 emissions.
Now, in the race to decarbonize the $410 billion global cement industry, scientists are creating new production methods and startups such as Brimstone, Fortera and Massachusetts-based Sublime Systems are putting them into practice.
“Our process emits no carbon dioxide. It avoids all carbon dioxide emissions, whether it comes from fossil fuels or limestone,” said Sublime Systems CEO Leah Ellis.
Sublime uses chemicals instead of heat and other minerals instead of limestone.
“By using electrochemistry to break down minerals at ambient temperatures, it actually allows us to use calcium-containing minerals to make cement instead of limestone, and that’s how we get to true zero rather than net zero,” Ellis explained. reason.
Like other new technologies, it comes with a higher price tag, but climate-forward companies like WS Development in Boston appear willing to pay more for cement. Its One Boston Dock Road will be the city’s largest net-zero office building, with ground-floor public spaces clad in Sublime cement.
“As people walk through this building every day, they will be able to interact with the products and learn more about a net-zero carbon future in the built environment,” said senior vice president Yanni Tsipis. .
Sublime recently received an $87 million grant from the U.S. Department of Energy that will cover half the cost of its first commercial plant in the state.
Its venture capital backers include Lower Carbon Capital, Engine Ventures, Energy Impact Partners, Prime Impact Fund, Siam Cement Group and MCJ Collective. It has raised $45 million in funding to date.
Ellis said Sublime Systems has conducted extensive testing of the product’s durability and expects it to be competitive with traditional Portland cement at scale. Once the new plant is up and running, she expects to produce 30,000 tons of clean cement per year. To put it into perspective, the United States produces approximately 90 million tons of cement per year.
“This is an unprecedented process and we’re competing against technologies that have been scaled for decades to a million tons per year. So, initially, like solar panels and wind turbines, we will have a cost premium, but our goal It’s a quick and huge impact,” Ellis said.
—CNBC Producer Lisa Rizzolo contributed to this article.
