Techno-Economic Analysis of Cement Decarbonization Pathways in California
Synapse conducted a comparative techno-economic analysis for Clean Air Task Force (CATF) on the role of commercially available and emerging technologies for decarbonizing California's cement industry. Since more than half of greenhouse gas emissions from cement production originate from calcination rather than fuel combustion, carbon capture and storage (CCS) is an important technology for deep decarbonization of the cement sector. Synapse modeled four CCS-based decarbonization pathways for a representative cement facility in California, comparing each to a conventional baseline plant. The four decarbonization pathways were: 1) CCS only; 2) electrification of the precalciner and kiln + CCS; 3) limestone calcined clay cement (LC3) + CCS; and 4) LC3 + alternative fuels + CCS.
Synapse found that all four pathways could achieve substantial emissions reductions, with LC3-based pathways offering the lowest lifetime abatement costs at approximately $100/tCO₂. LC3 uses less clinker per ton of cement than ordinary Portland cement, helping to reduce production costs. While electrification enables deeper decarbonization over time as California's electricity supply decarbonizes, the electrification pathway had the highest lifetime abatement cost due to the state's high cost of electricity. The analysis highlighted the tradeoffs among emissions reductions, energy use, capital investment, and operating costs across cement decarbonization strategies.