Co2-eating cement could create carbon-negative buildings

This article was taken from the July 2011 issue of Wired magazine. Be the first to read Wired's articles in print before they're posted online, and get your hands on loads of additional content by subscribing online.

For every one of the 2,800 million tonnes of concrete we use globally every year, 1.25 tonnes of CO2 are released. One possible solution? Novacem, a new type of cement that takes carbon from the atmosphere.

Common cement is made using limestone, which releases CO2 when it is reduced to powder by baking at 1,400°C. But Nikolaos Vlasopoulos, who founded Novacem in 2007, has created a production process that absorbs CO2 from the atmosphere. "The material is based on magnesium oxide," he explains. "Its low molecular weight means that, over the process, every tonne of cement absorbs 100kg more CO2 than it emits." The company aims to produce 25,000 tonnes of cement a year by 2015 -- and maybe build a greener future.

This article was originally published by WIRED UK