Cement is the largest manufactured product in the world by mass. In 2022 humans produced 4,2 billion tons of it (about 626 kg per capita). Combined with water, sand and aggregates cement is the glue to form concrete. Aside from water, there is no material we use more than concrete. Contractors can combine concrete with steel reinforcement bars to mould and create the build environment in which we experience our lives. The industry is interrelated with other major sectors such as energy and steel. Its supply chains are vast, deeply complex, with increasing degrees of fragmentation going downstream. This complexity is also reflected in the many ways cement and concrete markets can be (sub-) segmented, for example by cement use (concrete, mortar, etc.), concrete use (reinforced, non-reinforced, ready-mix, precast products, etc.), end-use (residential, non-residential, infrastructural, energy, etc.) to name a few.

Cement and concrete are versatile, low-cost, abundant and relatively local. Modern societies are hard to imagine without these materials. Realistically, cement and concrete are here to stay. Then again, current mainstream cement and concrete technologies are also the source of 8% of our CO2 emissions (about 600 kg per capita), which are “embodied” in our buildings and infrastructures. Roughly 60% of these emissions are “chemical” released by converting limestone into clinker, and 40% of doing so at very high temperatures by burning fossil fuels. With EU (and global) commitments for rapid and radical emission reductions, it is necessary to pull all scientific, economic, and regulatory levers to reduce the environmental impacts of the cement and concrete sector.

One default pathway to decarbonize cement (and indeed a major element in the sector’s strategy to decarbonize to net-zero by 2050) is to capture and store CO2 of current production processes (CCS). Technologies for CCS are in development and expected to increase the cost of cement. To avoid additional costs of future emissions as much as possible, accelerated deep-tech innovations are needed to fully negate or even absorb emissions by the sector in future. The breakthrough innovations sought with this Pathfinder Challenge aim to be more cost effective than CCS. Moreover, this Pathfinder Challenge encourages breakthrough innovations that utilize CO2. Such innovations can play an important role in future CCUS economies, and trigger future revenue opportunities for the sector by offering negative emissions at scale. However, CCS/CCUS technologies that are unrelated to cement and concrete technologies are out of scope of this Pathfinder Challenge.

This Pathfinder Challenge seeks to support breakthrough innovations and (alternative) pathways for decarbonized and carbon-negative cement and concrete. Future pathways must meet some important conditions to be ultimately successful.

The economical and abundant availability of feedstock at the place of production (cement) and consumption (concrete) is an important condition for implementing practically viable alternative cement chemistries, concrete mixtures and substitute materials.

Most of the consumption growth of cement (and associated CO2 emissions) is expected in developing nations. Therefore, if innovative (deep-tech) solutions for cementitious materials are to be adopted on a significant scale (a condition for “disruptive innovation”) they shall (at least in potential) be low cost and used easily by people with minimal training and scientific knowledge.

Ultimate success and technology adoption shall depend on meeting or exceeding the mechanical and operational performance levels of the incumbent mainstream cement and concrete technologies, which are also reflected in the various norms and standards.