Seaweed turns concrete greener as scientists slash cement emissions

Researchers from the University of Washington and Microsoft have developed a low-carbon concrete by incorporating powdered green seaweed into cement, achieving a 21 percent reduction in global warming potential without compromising structural strength. Cement production is a major contributor to global CO₂ emissions, responsible for about 10 percent of the total, primarily due to fossil fuel use and the calcination process. Seaweed, as a photosynthetic organism, acts as a carbon sink during growth and can be used in dried, powdered form without expensive processing, making it a promising sustainable additive for cement. To accelerate the traditionally slow trial-and-error process of optimizing concrete mixtures, the team employed a custom machine learning model that predicted the best seaweed-cement blends. This approach reduced the development time from an estimated five years to just 28 days. The researchers envision using this method to tailor cement formulations to local resources and conditions, potentially incorporating other bio-based materials like different algae species or food waste. Their work, funded by Microsoft Research and published in the