Not just another block in the wall, the process for creating Carbicrete-based concrete blocks absorbs more carbon than it emits, potentially revolutionizing the concrete industry. Production of cement, one of three essential components in concrete, is one of the worst GHG emitters on the planet estimated at 5% of all emissions. Carbicrete substitutes steel slag as the primary binder and carbon dioxide as the activator in cement-free concrete. The production of each tonne of Portland cement emits 1.9 kg NOx, 1.24 kg SOX, 0.052 kg VOC , 0.21 kg of particulate matter and 900 Kg of CO2 into the atmosphere, plus consumes 1.8 tonnes of natural resources, e.g. clay and limestone and 100-300 litres of water. In stark contrast, Carbicrete’s technology uses CO2 for curing, instead of heat and steam, so in addition to the emissions that are avoided by not using cement, CO2 is then captured permanently in the final product. In the end, the CO2 score per ton: Cement based concrete: 82Kg Carbicrere -55 Kg! No wonder Carbicrete is a finalist for the Carbon X Prize!