We buy steam from a neighbouring plant for a CBAM product. How is that heat counted?
Heat you import is added to your production process with the emissions of producing it. Use the supplier's actual fuel and boiler efficiency data where you can get it; without it, the monitoring rules give a fallback factor. Heat counts for every CBAM good, including steel and aluminium, unlike grid electricity.
How it enters the calculation
Measurable heat flowing into the production process carries an emission factor: tonnes of CO2 per terajoule of heat. Multiply the heat consumed by that factor and add it to the process's attributed emissions, alongside your own fuel.
What to ask the heat supplier
- The fuel burnt and its quantity for the period.
- Heat produced, so the factor per terajoule can be worked out.
- Whether the boiler also makes power, which needs a split between heat and electricity.
If the supplier will not share data
Use the fallback in Annex III of Implementing Regulation 2023/1773 and record why. A verifier will accept a documented fallback more readily than an unexplained number.
Keep the records
Steam invoices or meter readings by month, the supplier's factor and its basis, and how the heat was split if one meter serves more than one process.
What Senseible does here
Senseible reads fuel, electricity and production documents into dated, fingerprinted installation records, the starting point for the actual emissions an EU importer asks for.
Sources: Implementing Regulation (EU) 2023/1773, monitoring rules, CBAM Regulation (EU) 2023/956, consolidated, European Commission, CBAM legislation and guidance
Last reviewed 2026-10-22.