According to a new study by researchers at the University of California, Davis and Stanford University, construction materials used in buildings have the potential to lock away billions of tons of carbon dioxide. The study, published in Science, shows that storing CO2 in buildings could be a major contributor to efforts to reduce greenhouse gas emissions.
Overall efforts in carbon sequestration take carbon dioxide – either as it’s being produced or once it’s already in the atmosphere – and store it away. Storing it might involve injecting it into underground caverns or deep in the ocean. Alternatively, storing it might involve converting it into a stable form using chemical reactions. These various strategies involve both practical challenges and potential environmental risks.
The new study suggests that many materials that are already produced in large quantities have the potential to store carbon dioxide. These include concrete, asphalt, plastics, wood, and brick. More than 30 billion tons of these materials are produced worldwide every year.
Ways to accomplish carbon storage include adding biochar into concrete, using artificial rocks loaded with carbon as concrete and asphalt aggregates, plastic and asphalt binders based on biomass instead of petroleum, and including biomass fiber into bricks.
The largest potential is using carbonated aggregates to make concrete. Concrete is by far the world’s most popular building material with more than 20 billion tons being produced each year.
The feedstocks for these ways to store carbon in building materials are mostly low-value waste materials, so the economics of implementing these carbon sequestering strategies are likely to be quite favorable.
**********
Web Links
Storing Carbon in Buildings Could Help Address Climate Change
Photo, posted October 19, 2022, courtesy of Alexandre Prevot via Flickr.
Earth Wise is a production of WAMC Northeast Public Radio