Green cement soaks up CO₂

Novacem, a spin-out company from Imperial College London's Incubator sector, has developed a 'green' cement that uses less energy to make than conventional Portland cement and absorbs a net amount of carbon dioxide, so potentially reducing the carbon footprint of the construction industry.

Conventional Portland cement used by the construction industry worldwide uses 3-4 gigajoules of energy per tonne manufactured, and releases between 650 and 800 kilograms of CO₂. Every year more than 2.5 billion tonnes of Portland cement are produced with this number expected to increase to five billion tonnes per year by 2030.