Our 2050 Roadmap: The 5C Approach
Cement’s main end-product is concrete, which is the most commonly-used material on earth after water. Concrete is manufactured by mixing cement with water and aggregates with small quantities of chemical admixtures used to improve the properties of the concrete and
to meet specific product requirements, where cement represents about 10-15% in this mix. The direct CO2 emissions related to concrete largely come from cement production. The largest indirect CO2 emissions come from transportation of concrete to the end user.
Opportunities to Achieve CO2 Reductions for Concrete
How can we reduce emissions from concrete?
Digitalisation, Improved Mix Design and New Admixtures
Digitalisation offers significant opportunities to reduce CO2 emissions from concrete. Improved data and data processing will enable builders to get the exact amount of concrete delivered on site to get the job done. Digitalisation will also help monitor the concrete during transport and ensure it is poured correctly. Data for the cement and concrete will be available to the contractor and the purchasers of the building to enable the carbon footprint to be determined and also to show the source of the materials used in construction as well as monitor the energy performance of buildings during their life. Digitalisation can also help improve aggregates grading and optimise admixtures.
Digitalisation, improved mix design and new admixtures can reduce cement in concrete by 5% in 2030 and 15% by 2050.
Low carbon cements and the use of cement substitutes
The use of low carbon cements in concretes will reduce the overall carbon footprint for concrete. Fly ash, granulated slag, silica fume, pozzolan and other cement substitutes can also be added at the concrete manufacturing stage. CO2 savings for this have already been included in the cement manufacturing stage.
One of the biggest sources of CO2 emissions related to concrete production is the transport to the job site and the energy needed to pump the concrete to where it is needed. It is assumed that by 2050 all transportation will be handled by zero emissions vehicles with the move to electric, hydrogen or a combination of both.
How can policy support this transformation?
As well as encouraging the development of markets for low-carbon products mentioned above, policies can also play a leading role to incentivise the use of digitalisation across the concrete industry.
Crucially, policies should be based on a full lifecycle approach, and also look at adequate training of all actors down the value chain.
Policies based on material neutrality and the life-cycle performance of products should be encouraged across all EU legislation. The CO2 footprint of products should be based on a cradle-to-grave lifecycle approach that goes beyond placing a product on the market and also takes into account the performance of the product during its use and after its useful life.
Delivering carbon neutrality in the building sector will require appropriate skills and new building techniques. The upcoming Sustainable Built Environment strategy should promote cooperation between architects, local authorities and engineers. It should foster skills and training to deliver energy-efficient designs and lower-carbon concrete mixes.
Innovation in action
Some examples of research projects aiming to reduce CO2 emissions
Solidia offers solutions that could lower emissions related to cement manufacturing by 30-40%. As well as technology to cure with CO2 rather than water, trapping the CO2 in the concrete resulting in a 50% lower CO2 footprint. These types of concrete would require specialised curing chambers and would thus only be suited to precast operations.