Current practice is to grind and burn enormous amounts of limestone, releasing equally enormous amounts of CO2 to the atmosphere. But isn’t there some way to reverse the chemical process and still end up with building material?
First step is to reduce cement emissions; second step is to find a means to actually turn the world’s countless concrete construction sites into carbon sinks, reabsorbing some of that CO2 we emit and safely storing it in sturdy molecules that allow us to live in houses with walls that can carry many floors and a roof.
Let’s be optimistic and say new research shows we’re almost halfway.
Under 450 Scenario we are all essential
In the global effort to stabilise atmospheric greenhouse gas concentrations at no more than 450 ppm CO2 equivalents the first thing to do is lower emissions as far as possible. To achieve this UN climate target the energy sector deserves prime focus, as both energy efficiency improvements and maximised transition to zero carbon sources are essential. Of course that big chunk of deforestation and other land use carbon emission sources will have to abated as well.
But there is one other industry we shouldn’t ignore – but mostly are: cement. It is said to be responsible for over 5 percent of all anthropogenic emissions – and for a single industry that is more than perhaps it may sound.