The Size of Concrete's Carbon Footprint

It's interesting when scientists begin picking out random objects and point out the probable size of their carbon footprint on a global scale.

This is what some scientists have done with concrete. A new report has been released that suggests that up to 5 per cent of the world's carbon footprint comes from the concrete industry. That includes the energy use and the carbon dioxide by-product from the production of cement.

There have also been studies that have found that some carbon dioxide is absorbed into concrete, even decades after it has been placed, in the formation of calcite. A new study yet to be released will also suggest that the absorption of CO2 may extend beyond calcite to remove carbon dioxide from the air which actually lowers concrete's overall carbon footprint.

The absorption of CO2 into concrete has been known for years in the formation of calcite (calcium carbonate). But the careful analysis of concrete samples have revealed that other compounds may be forming.

While solving the world's carbon emissions problems is not as simple as paving the entire world in concrete to suck up the carbon dioxide in the atmosphere, it is certainly interesting to know that recycling concrete could turn into a net-carbon footprint exercise if done right.