SEATTLE — University of Washington and Microsoft researchers created a new type of concrete that could cut its carbon footprint.
The secret ingredient? Seaweed. According to the team, seaweed can absorb more carbon than it releases.
The researchers published their findings on July 8 in Matter.
“Cement is everywhere — it’s the backbone of modern infrastructure — but it comes with a huge climate cost,” said senior author Eleftheria Roumeli, a UW assistant professor of materials science and engineering. “What makes this work exciting is that we show how an abundant, photosynthetic material like green seaweed can be incorporated into cement to cut emissions, without the need for costly processing or sacrificing performance.”
Cement is the key component of concrete—and contributes to about 10% of all carbon dioxide emissions worldwide.
The seaweed-fortified cement has a 21% lower global warming potential while retaining its strength.
So, how is it made? The researchers mix in dried, powdered seaweed with cement. Researchers built and used a machine learning model to speed up the process. Without the machine – it could take years to find the perfect formula. It takes about a month for concrete to fully cure. Instead, it took the UW team a little under a month.
The team will continue to test how the seaweed-infused cement to see how the formula affects the performance of cement.
Researchers said their larger goal is to generalize the work out to different kinds of algae or even to food waste.
“By combining natural materials like algae with modern data tools, we can localize production, reduce emissions, and move faster toward greener infrastructure,” Roumeli said. “It’s an exciting step toward a new generation of sustainable building materials.”
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