Büyükçekmece Cement Plant

1 · Facility identity

Company / operator

Akçansa

Plant name

Büyükçekmece Cement Plant

Sector (CBAM scope)

cement

Location

Büyükçekmece, Türkiye

Nameplate capacity

2,500,000 t/y

2 · Emission figures (tCO₂)

95% conformal prediction interval (global, n=21 calibration): 969,379 – 3,310,134 tCO₂. Restricted to cement stratum: 1,055,703 – 3,039,465 tCO₂ (subject to small-n undercoverage).

3 · Source citation for audit-grade Scope 1

Allocated from Akçansa 2025 group Scope 1 (5,484,015) × Büyükçekmece clinker share 27.6%. Group total is audit-grade; per-plant split is by disclosed clinker tonnage, not directly disclosed.

4 · Methodology (cf-corrected formula)

The headline method is a closed-form physics baseline: Scope 1 ≈ nameplate capacity × route emission-factor × capacity factor, using only operator-published numbers. It is evaluated leave-one-plant-out: each plant's route emission-factor is derived only from the other audit-grade plants in its route, so no plant contributes to its own prediction. Headline: +82.3% log-MAE reduction vs the EU CBAM default across the 19 validatable plants (of 21 audit-grade; two single-plant routes — N₂O-controlled and blender fertilizer — cannot be independently validated and are excluded). External validity: the same formula on 372 EUTL-verified EU cement installations gives a median ratio ≈1.0 vs the EU default's ≈2.5×. An optional in-browser WebGPU model (iz) is shipped as a demo only; it does not beat this formula at current data scale.

5 · Verifier checklist

1. ☐ Confirm Scope 1 line item in the cited source matches the value above (tCO₂ basis; not CO₂-equivalent if different).
2. ☐ Verify operator's verification statement (ISO 14064-1 / TSRS / financial audit) attached to the source.
3. ☐ Cross-check capacity against latest published cement / steel / aluminum / fertilizer association registry.
4. ☐ If using the formula prediction as input to a CBAM Article 4(2) actual-emission declaration: it is a model estimate, not a measurement. Verifier must independently support the underlying activity data.
5. ☐ Confirm the conformal prediction interval covers the operator's claimed Scope 1.

6 · License and citation

TR-MRV-Bench v0 is Apache-2.0 licensed. The benchmark, methodology, and per-facility data are public at github.com/abgnydn/iz and iz-mrv.pages.dev. Cite: Günaydın (2026), "TR-MRV-Bench: a public per-facility emissions benchmark for Turkish CBAM-scope industry, with a physics baseline that beats the EU CBAM default by +82.3% (leave-one-plant-out, n=19)."