How do I calculate CBAM embedded emissions when I buy the same steel input from two suppliers?
Use each supplier's embedded emissions per tonne for the tonnes you actually consumed in the period. If you cannot trace which coil went into which product, weight the two figures by tonnes consumed. Any tonnes without supplier data take the default value.
Steps
- Tonnes consumed from each supplier, from issue or stock records.
- Each supplier's embedded emissions per tonne for the same period.
- Weighted figure = sum of tonnes × factor ÷ total tonnes.
- Use the default value for any tonnes without supplier data.
Keep it traceable
Record the supplier, heat or coil numbers and the period of each figure. A verifier will check that the tonnes match your purchase and stock records.
Example: coil from two mills
- 600 t × 2.0 t CO2/t = 1,200 t
- 400 t × 2.4 t CO2/t = 960 t
- 2,160 ÷ 1,000 = 2.16 t CO2 per tonne of coil
What Senseible does here
Senseible reads fuel, electricity and purchase invoices into dated, fingerprinted installation records, the starting point for the actual emissions an EU importer asks for. It does not file CBAM declarations or verify emissions.
Sources: CBAM Regulation (EU) 2023/956, consolidated, Implementing Regulation (EU) 2023/1773, production routes and monitoring, Implementing Regulation (EU) 2025/2621, CBAM default values
Last reviewed 2026-10-22.