Why elementary flow output of carbon dioxide does not have a characterization factor?

Question

Dear OpenLCA community,

I've found a problem in openLCA when evaluating a process that has an elementary flow output of 1 kg of carbon dioxide using the IPCC 2021 method from ecoinvent 3.10 LCIA Methods. Its result is 0 kgCO2-eq while running the same method with openLCA LCIA Methods v2.4.2 gives the results as 1 kgCO2-eq. There seems to be a problem with ecoinvent's method, which does not have a characterization factor with an elementary flow of carbon dioxide.

How can I modify this so that it gives a characterization factor of 1 kgCO2-eq/kg for the elementary flow of carbon dioxide?

Any suggestion/help?

All the best,

Fernando

Comments

Dear Fernando,

May I ask you to provide a screen of your process and maybe the uuid of the flow that is not charachterized?

Best regards,
Sarah Serafini (GD)

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Dear Sarah,

Thank you for your response.

Another user has already answered my question and it solved my problem. However, I appreciate your willingness to assist.

Best regards,
Fernando

Answer 1

Hi Fernando,

the ecoinvent database itself does not use the elementary flow called "carbon dioxide". The one that is in the database (carbon dioxide, Category: Emissions/Emissions to soil/ Emissions to soil, unspecified) has no characterization factor and is not used at all. Don't use this one! The ecoinvent database always uses "carbon dioxide (fossil)" or "carbon dioxide (biogenic)" (and some more). So please cross-check that you use those following the logic presented in the ecoinvent database. You might used the wrong one but due to the interoperability of the openLCA method package, it is accounted for in openLCA method package but not within the ecoinvent methods.

Hope this helps

Comments

Hello Jonas,

Thank you for your response. That did clear things up. I will go on and keep using the openLCA LCIA Methods as it seems more accurate.


Kind regards,
Fernando (EcoEd)