Low-carbon cement and concrete

Cement and concrete are the second-most used substance in the world after water and the second-largest source of direct CO₂ emissions from industry. They are used as building materials for a wide array of end uses, including commercial and private buildings and other infrastructure such as bridges, roads or dams.

Around two thirds of the emissions in cement and concrete stem from the process of deacidifying limestone as part of producing clinker, a key component of cement. The remaining third are emissions related to energy supply. In contrast to other sectors such as the chemical industry, most emissions occur at the production stage and not in subsequent life cycle stages such as the use phase and the end-of-life treatment. However, a climate-friendly use and re-use of cement and concrete can help to drive down cumulative emissions of the sector.

Several strategies will play a key role in the successful transition of the sectors to climate neutrality. First, the CO₂ intensive part of cement and concrete materials need to be used in a much more efficient and circular manner, for example by reducing the clinker factor in cement and the cement share in concrete, by developing innovative concrete chemistries, as well as recycling both cement and concrete. Second, the design and construction of buildings and other infrastructure needs to become more material efficient. Third, the energy required for cement and concrete production needs to come from renewable sources such as renewable electricity.

Fourth, the use of carbon capture and storage (CCS) will be necessary for residual and unavoidable process emissions. And fifth, by combining biomass and carbon capture and storage (BECCS), cement production can even contribute to generating negative emissions which will be needed in a net-zero world. For this last solution to be sustainable, biomass use needs to follow strict sustainability criteria and be closely coordinated among demand-side sectors.

Agora Industry develops concepts and policy recommendations based on the above key elements to steer the transition in the cement, concrete and construction sector towards climate-friendly solutions.