System Dynamics Model for Decarbonization Pathways in the Global Cement Industry

Cement production remains one of the largest industrial sources of anthropogenic carbon dioxide (CO2) because of process emissions from limestone calcination and high-temperature fuel combustion. The primary objective of this study is to quantify the comparative effects of isolated and integrated mitigation portfolios on annual and cumulative global cement emissions through 2050 and to identify the principal leverage points needed for deep sectoral decarbonization. To achieve this, a global aggregate system dynamics model was developed and anchored to a 1990–2022 historical production baseline. The model evaluates five internally consistent scenarios: business-as-usual (BAU), efficiency and alternative fuels (EFF), materials efficiency and clinker substitution (MAT), carbon capture and storage (CCS), and an integrated net-zero-emission (NZE) pathway. The results show that while efficiency improvement alone (EFF) reduces 2050 annual emissions by 14.0% relative to BAU, it does not reverse sector-wide emissions growth. Deep decarbonization requires both substantial clinker-demand reduction (MAT, 33.2%) and broad CCS deployment (CCS, 61.1%). Only the integrated NZE pathway achieves an 87.9% reduction, lowering 2050 direct emissions to 325.8 Mt CO2. Cumulative emissions analysis further shows that delayed structural mitigation results in a large long-term carbon burden, with BAU accumulating 72.86 Gt CO2 over 2023–2050 compared with 40.07 Gt CO2 in the NZE case. A 5000-run Monte Carlo uncertainty analysis confirms that the scenario ranking remains robust under bounded-parameter variation and identifies CCS penetration and the clinker-to-cement ratio as the most influential determinants of long-term mitigation performance. Overall, the study provides a reproducible and policy-relevant framework showing that cement decarbonization cannot rely on single-technology measures, but instead requires coordinated early action across materials efficiency, alternative fuels, and large-scale carbon capture.