Can we switch to a newer carbon factor next year, or are we stuck with the one in our monitoring plan?

You can switch, but not casually. The monitoring plan must name the value you use, and a new value must be evidenced as more adequate and representative for your fuel or material. If a value changes often, such as every year, name its source in the plan and set up a yearly update step instead.

What the guide says

• To keep figures consistent over time and prevent arbitrary changes, you must lay down in the monitoring plan which values you are using.
• If a new value is used because it is more adequate and representative for the fuel or material than the previous one, this must be evidenced.
• If the values change more frequently, such as on an annual basis, the authoritative applicable source shall be laid down in the monitoring plan instead of the value itself.

Two cases

Case one is a fixed figure that does not move, such as a table value. The plan states the value. If you change it because a new figure is more adequate and representative for your material, the guide says this must be evidenced, and the change goes into the plan.

Case two is a figure from a source that is updated, such as a country's national greenhouse gas inventory. The plan then names the source. The guide says you need a procedure that allows regular updating.

The guide's own example of the update step

It suggests that a defined person is responsible for updating the value once a year before compiling all emissions data. That person looks up the latest national inventory and finds the factor needed.

The guide recommends telling the verifier about plan changes, at the latest at the next regular verification. See the separate page on plan updates.

Example: a yearly update log

• Plan wording (example): 'Coal emission factor: the value in the country's latest national inventory submission to the United Nations Framework Convention on Climate Change. Updated each January by the accounts head.'
• 12 January 2027: accounts head looked up the latest submission. Factor unchanged from last year. Initialled and dated.
• 10 January 2028: factor changed. New value, source page and date written in the log. Verifier told at the next regular verification.

The log format is an example. The guide requires the procedure and the named source, not this layout.

What Senseible does here

Senseible reads fuel invoices and electricity bills into dated, fingerprinted records. It does not run lab tests, write a monitoring plan or verify a CBAM figure.

• Standard values, Type I and Type II
• Update the monitoring plan after a plant change
• What a monitoring plan must contain
• CBAM readiness for exporters

Sources: European Commission, CBAM Guidance No. 3, methods for calculating embedded emissions (14 August 2026)

Last reviewed 2026-11-07. Facts are from Guidance No. 3, section 4.6.1.4 (Fixed values and the paragraph that follows the Type II list), dated 14 August 2026. The two cases and the log layout are my summary of those lines. The guide's example refers to national greenhouse gas inventories; whether a given fuel has a national factor is for the plant to check.