London students win award for low-carbon concrete

Two London PhD students, Sam Draper and Barney Shanks, have received the international OBEL award for their technology that de-carbonises cement, a major component of concrete. Their invention could significantly reduce the carbon footprint of the construction industry.

The OBEL Award is handed out annually for architectural contributions that help human development, and for 2022 it focused on lowering emissions and more eco-friendly processes.

Concrete flooring, beams and roofs are frequent components of commercial construction projects. Concrete is durable, cost effective and strong, but is a carbon emission-heavy material, largely because of its use of cement. The technology developed by the two students replaces a portion of the cement mixture with silica, and this reduces the concrete’s carbon emissions by 40%.

Silica also captures carbon from the atmosphere to further reduce emissions. This makes it a double eco-friendly material that reduces overall concrete carbon emissions to zero. Concrete flooring containing this silica cement could benefit an industrial site by consuming waste CO2 from industrial processes.

In theory, it is possible to produce concrete without any carbon emissions, but there is no simple or cost-effective way to do this yet. The raw materials needed to produce zero carbon cement are scarce, whereas the silica used in the concrete developed by Sam Draper and Barney Shanks is readily available.

The two students founded the Seratech organisation to develop and promote their cement technology. They are hoping that architects will use their low-carbon concrete in future building projects.