Growing Sustainable Carbon-Negative Cement with Algae

The production of cement is a well-known contributor to greenhouse gas emissions, but new research hopes to change that by growing cement with algae in ponds.

The research focuses on the harvesting of coccolithophores, a type of algae that grows in the sunlight zones of the world’s oceans. Using sunlight and seawater, the algae then consume dissolved CO2 to produce calcium carbonate shells that cover their cells, which can ideally be harvested on a large scale to supplement limestone in cement.

Teams from the University of Colorado Boulder and the University of North Carolina Wilmington are working together on the research, which was recently awarded more than $3 million in funding from the Department of Energy for continued research.

Alternative behaves 'exactly like concrete'

“We’ve demonstrated that we can create or really grow concrete-like alternatives that look and feel and behave exactly like concrete,” said Wil Srubar, an associate professor in civil, environmental and architectural engineering and CU Boulder’s materials science and engineering program.

Srubar speaks about the research in a new video highlighting the initiative from the University of Colorado Boulder.

He said the difference is that concrete produced from algae will be grown and would exhibit low to zero carbon emissions.

“Nature, I believe, has figured out solutions to all of our problems and we just have to pay a little bit more attention,” Srubar said.

The cement-producing algae would be grown in ponds and aims to increase the amount of carbon stored in buildings, acting as a carbon sink.

Other sustainable efforts in the concrete industry

The industry has seen an acceleration of efforts focused on sustainability and companies engaged in every aspect of concrete production are beginning to consider greener approaches.

In February, CEMEX announced that it is the first building materials company to complete a large-scale, multi-country pilot program using fully electric ready-mix concrete trucks.

Companies like Unicon and Volvo Trucks have also agreed on long-term collaborations that aim to develop and implement complete truck and body electric solutions for the concrete industry.

Other groundbreaking research that has excited the industry of late includes emerging technologies in Europe focused on concrete that can charge electric cars as they travel.