For hydrogen made by partial oxidation, do the oxygen plant's emissions count under CBAM?
No. The EU's CBAM Q&A 4.12 says oxygen is an input to partial oxidation and autothermal reforming, but it is not listed in Annex I of the CBAM Regulation, so it is not a precursor. Fuel and electricity emissions of the air separation unit are left out of hydrogen's embedded emissions.
What still counts
- CO2 from converting the feedstock, natural gas or heavier hydrocarbons, into hydrogen. Q&A 6.2 confirms the conversion of natural gas to hydrogen counts as direct emissions.
- Fuel burnt for the reformer, gasifier or steam that serves the hydrogen process.
- Only direct emissions: hydrogen is one of the goods for which CBAM counts no indirect emissions.
What stays out
- Fuel and electricity used by your own air separation unit.
- Bought oxygen, which carries no precursor emissions.
Records to keep
If one boiler supplies steam to both the reformer and the air separation unit compressors, meter the steam to each, or split the boiler fuel on a method your verifier can follow. Otherwise the oxygen plant's share stays in the hydrogen figure.
Example: autothermal reformer, one year
- Feedstock conversion and fuel for the hydrogen process: 50,000 t CO2
- Boiler fuel for steam to the air separation unit: 4,000 t CO2, left out
- Hydrogen produced: 10,000 t
- Figure: 50,000 / 10,000 = 5.0 t CO2 per tonne, not (50,000 + 4,000) / 10,000 = 5.4
Example figures.
What Senseible does here
Senseible reads gas, fuel and electricity invoices into dated installation records, so the air separation unit's share can be kept apart. We build it from your records, check every figure in-house, and an accredited verifier we partner with signs it off. Have your own verifier? Send it to them.
Sources: European Commission, CBAM Questions and Answers (15 October 2026), question 4.12, 4.16 and 6.2, CBAM Regulation (EU) 2023/956, consolidated
Last reviewed 2026-11-01.