Figure 20abc. Emissions by Sector: Business as Usual, Moderate Adoption, and Rapid Adoption
Analysis by Beacon Economics
Highlights
Several assumptions shape the base case scenario. The first is that as coal usage for electricity generation is drawn down, cement manufacturers’ source of fly ash becomes increasingly limited; the loss of this SCM, and limitations in accessing other SCMs, leads the average market cement to slightly increase in average emissions over time. Only cement used for roadways sees increased carbon efficiency due to state regulations. In the moderate and rapid adoption scenarios, new SCMs and other green cement technologies replace fly ash and help continue to drive down average emissions per ton.
In both of the accelerated models, it is assumed that sectors where state and local governments have significant purchasing and regulatory power—such as road construction and repair—would be the earliest and most rapid adopters of green cement, while private construction, such as housing, would be slower. Additionally, certain uses that require high-strength concrete for safety regulations, such as dams, would be among the slowest to adopt green cement as safety concerns would lead to a reluctance to change formulas. Most rates of adoption within sectors were modeled as logistic functions, with intra-sector emissions therefore following an inverse logistic function; slow adoption at first as new materials gain industry acceptance, followed by a period of rapid switchover, with a slow final period of adoption by stubborn stragglers and edge-case uses where green cement may be inappropriate.