How a stackable EAC framework grows the market while rewarding deep decarbonization — without excluding any credible solution.
A stackable, performance-based EAC framework includes all credible solutions while preventing a race to the bottom.
Many winners, not one: the market must deploy SCMs, novel binders, and CCS simultaneously—each capped at its physical substitution limit.
Market growth depends on broad buyer participation, which requires affordable entry points layered with deeper-impact options.
A natural price gradient emerges: low-cost SCMs anchor the base layer, scarce high-abatement technologies command a premium above 50% reduction.
Cement and concrete decarbonization is not one technology problem — it is a system problem. Clinker production is concentrated in existing plants that are expensive and slow to replace. Concrete use is distributed across millions of projects with diverse performance needs.
The sector must deploy all credible levers at speed: SCMs, novel binders, process optimization, fuel switching, and carbon capture. But if every solution competes on price alone, buyers gravitate to the cheapest certificates and high-impact technologies like CCS get chronically underfunded.
Low-Cost, Mature
Fly ash, GGBFS, limestone
Mid-Cost, Moderate Risk
Emerging SCMs, novel cements
High-Cost, High-Impact
CCS, carbon mineralization
CTC's proposed approach starts from a simple idea: let the market include all credible solutions, but align EAC usage with the actual physical decarbonization potential of each one.
All qualifying SCMs, new binders, process optimizations, CCUS projects, and other interventions can generate EACs.
Each solution is assigned a decarbonization factor AND a maximum substitution share — the fraction of a typical mix it can realistically replace.
Buyers can retire EACs from a given solution only up to that substitution share. To go beyond, they must stack EACs from additional, deeper-decarbonization technologies.
Concrete Example: SCM + CCS
SCM EACs (0–50%)
Buyers can retire SCM-linked EACs to cover up to 50% of embodied emissions. These will typically be lower priced because SCMs are more available.
Beyond 50%
To claim additional decarbonization, buyers must add CCS-linked or other high-abatement EACs. These are scarcer and more expensive, reflecting deeper impact.
The result: A base layer of abundant, lower-cost SCM decarbonization + a second layer of scarce, higher-cost CCS/novel binder decarbonization.
Toggle SCMs on or off and adjust the demand slider to see how market dynamics change. When SCMs are included, a broad supply base keeps prices low enough for broad buyer participation.
Avg EAC Price
$67
/tonne CO₂
Buyer Participation
55%
of potential buyers
Demand Level
40
units
The concrete industry's 4-gigaton challenge cannot be solved by any single technology. SCMs, novel binders, carbon capture, and process optimization all have roles to play — but only if the market structure rewards each at the right level. A stackable, performance-based EAC framework creates a market that is broad enough to attract mainstream buyers, deep enough to fund frontier technologies, and structured enough to prevent the race to the bottom that has plagued voluntary carbon markets. This is how we build a real market for low-carbon concrete.
Return to the series overview to explore other dimensions of the concrete decarbonization challenge.