Reconstructing a defensible CBAM emissions baseline
A plant that had supplied Europe for years, with production data that had never been kept for carbon.
The situation
The plant had been supplying cement to European customers but had never maintained its production data specifically for CBAM. When its EU customer requested embedded-emissions information, the plant supplied a spreadsheet containing annual coal consumption, annual electricity consumption, clinker production, cement production and total cement dispatched.
At first glance the information appeared sufficient. It was not. The initial data review identified inconsistencies between the plant's production, procurement and finance records.
Data as first reported
| Parameter | Plant-reported figure |
|---|---|
| Clinker production | 1,780,000 t |
| Cement production | 2,410,000 t |
| Coal consumption | 278,600 t |
| Petcoke consumption | 36,400 t |
| Alternative fuel | 41,800 t |
| Electricity | 212 GWh |
| EU cement exports | 164,000 t |
| Reported emissions intensity | 0.694 tCO₂e/t cement |
Data-quality findings
- 01Fuel duplicationApproximately 7,600 tonnes of fuel appearing in the monthly procurement ledger had already been included in kiln consumption records.
- 02Alternative fuel classificationThe plant had reported all alternative fuel as fossil-derived. The dataset did not distinguish between fossil fraction, biomass fraction and waste-derived material.
- 03Electricity allocationOne electricity meter covered clinker production, cement grinding, packing and captive utilities. No allocation methodology existed.
- 04Production reconciliationCement dispatch data did not reconcile with the production database.
- 05Process emissionsThe original calculation focused heavily on fuel combustion and did not adequately document the plant's process-emissions methodology.
Step 01. Installation boundary
- Raw material preparation
- Kiln and precalciner
- Clinker
- Cement grinding
- Packing
- Dispatch
Reconstruction
- 02Fuel reconciliationProcurement records were reconciled against weighbridge records, kiln logs, monthly inventory and laboratory records.
- 03Alternative fuel classificationThe alternative-fuel stream was separated into its relevant fractions and treated according to the applicable CBAM methodology.
- 04Electricity allocationPlant electricity consumption was separated between the relevant production processes instead of applying the entire electricity bill to cement production.
- 05Production reconciliationClinker production, cement production, internal transfers and dispatches were reconciled to establish a consistent production dataset.
- 06Emissions calculationThe emissions model was rebuilt using fuel quantities, fuel emission factors, process-emissions data, electricity consumption, production quantities and product allocation.
Final assessment
tCO₂e per tonne of cement. The result was higher, not lower. That was intentional. The objective was not to produce a smaller number. It was to produce a defensible one.
Deliverables
- Installation boundary document
- Fuel reconciliation
- Electricity allocation methodology
- Production reconciliation
- Emissions calculation workbook
- Product-level emissions allocation
- Data-gap register
- Evidence register
- CBAM reporting data pack
- Verification-readiness checklist
Outcome
The plant moved from an unsupported emissions estimate to a structured emissions dataset capable of being taken through the appropriate CBAM verification and reporting process.
A credible CBAM assessment does not make the emissions number smaller. It makes the number traceable.
Case Study 01 · Cement · Simulated industrial assessment. Representative plant data. No client is identified.