How close are we to cement without the carbon?Can we make concrete without wrecking the climate?
or, simply: Can we make concrete without wrecking the climate?or, precisely: How close are we to cement without the carbon?
Cement is about 8% of global CO2; low-clinker chemistries and carbon capture can cut it deeply, but not yet at commodity cost and scale.Making cement pumps out huge amounts of CO2. New recipes and capture can slash it — if they stay cheap enough to use everywhere.
We are here
Brevik operates at industrial scale — Brevik remained operational with 400,000 tCO2/year design capture, equal to about half the plant's emissions. Next up — GeZero targets full capture (expected 2029).
01 · Where we stand
Four tests between here and the goal
Each threshold is a falsifiable claim with a named next test. We move the meter only when a result is public.
Industrial Low-Clinker CementUse much less clinker✓ Achieved · February 2023
100%
Proven byThe Saint-Pierre-la-Cour calcined-clay line reached industrial nameplate, though delivered tonnes were not disclosed.
Drop-In Alternative BinderReplace the kiln chemistryEarly
35%
Next testA novel-route producer must run a kilotonne-scale plant and publish strength, durability, EPD and cost data.
Full-Chain Cement CCSStore kiln carbon permanently✓ Achieved · August 2025
100%
Proven byThe first Brevik cargo was injected 2,600 metres beneath the North Sea.
Near-Zero Commercial FleetScale beyond one plantEarly
10%
Next testTrack final investment decisions, commissioning and certified output for the 35 Mt project pipeline.
THRESHOLDS — Thresholds for Near-Zero Cement.
Scale
Measured Projected Goal region
NOTE — The existing candidate metric is retained, but cement boundaries and product mixes vary. Historical values are industry GNR estimates, not a census. The IEA near-zero threshold slides from 125 kgCO2e/t at 100% clinker to 40 kgCO2e/t at lower clinker ratios, so 125 is an upper ceiling rather than one universal goal. The 2030 point is derived from GCCA's stated percentage target and is not achieved performance.
02 · How we got here
The record behind the verdict
Major events set large; context events set small but never hidden. Everything below the TODAY rule is a schedule, not a result.
The Clinker Age moved the field from portland cement is patented to ransome patents rotary kiln. The results narrowed the next question without closing it.
1824
Portland cement is patentedTheory
Joseph Aspdin patented artificial stone made by calcining limestone and clay, naming it Portland cement.
Pilots, Standards and Pledges moved the field from calera shuts after demonstration to lc3 reaches permanent production. The results narrowed the next question without closing it.
2014
Calera shuts after demonstrationSetback
Calera closed after placing roughly 100 tonnes of low-carbon material, showing chemistry did not guarantee a business.
Full-Chain Scale Test moved the field from fortera opens redding plant to announced capacity reaches 35 mt. The results narrowed the next question without closing it.
2024
Fortera opens Redding plant
A 15,000 t/year mineralized-cement plant opened; initial 15% blends cut concrete emissions about 10%, not 70%.
Events outside the declared eras moved the field from calcined clay reaches 500 kilotonnes to industry net-zero deadline arrives. The results narrowed the next question without closing it.
2023
Calcined clay reaches 500 kilotonnes
Holcim opened a line rated for 500,000 t/year of cement with 50% lower CO2 than CEM I, based on company claims.
The learning curves and comparisons that justify each threshold's percentage. Every series is measured, with the source event linked in the timeline above.
The descent to near-zero
The old curve runs out of road
485kgCO₂e/t to ceiling
NOTE — Most historical progress came from efficiency and clinker substitution; the curve remains far above the IEA near-zero band. The dashed segment is a visual continuation to the metric goal, not a claimed achieved trajectory.
Scale ranges from novel-binder pilots to industrial SCM production. The products and emissions cuts are not equivalent: the Ghana point is calcined clay, not finished cement.NOTE — Scale ranges from novel-binder pilots to industrial SCM production. The products and emissions cuts are not equivalent: the Ghana point is calcined clay, not finished cement.Capture equipment is moving from pilots toward million-tonne projects; the 2029 points are scheduled capacities, not operating results.NOTE — Capture equipment is moving from pilots toward million-tonne projects; the 2029 points are scheduled capacities, not operating results.The earlier value is implied by IEA's reported 30% rise to 35 Mt. Both values are announced 2030 capacity, not production.NOTE — The earlier value is implied by IEA's reported 30% rise to 35 Mt. Both values are announced 2030 capacity, not production.Efficiency improves slowly and cannot eliminate limestone process emissions; the 2030 and 2050 values are IEA pathway milestones.NOTE — Efficiency improves slowly and cannot eliminate limestone process emissions; the 2030 and 2050 values are IEA pathway milestones.
100%-clinker threshold125 kgCO2e/t
Low-clinker threshold40 kgCO2e/t
COMPARISON — The IEA near-zero limit becomes more stringent as clinker content falls, preventing dilution from masquerading as deep decarbonization.
Announced capacity35 Mt/year
Implied required capacity350 Mt/year
COMPARISON — Announced 2030 near-zero cement capacity is only one tenth of the IEA-aligned requirement.
Capture nameplate400000 tCO2/year
Approximate plant emissions800000 tCO2/year
COMPARISON — Brevik's design captures only about half of the host plant's emissions.
Low-end cost premium75 %
High-end cost premium150 %
COMPARISON — Early CCS cement plants are estimated to cost substantially more than conventional production.
04 · What it unlocks
If the remaining tests pass
Downstream capabilities, drawn dashed because they depend on results not yet in.