Difference in results

Question

Hello

I have a problem due to a big difference in results obtained by the same model.

In the file enclosed you can see the results one obtained by the model using Ecoinvent 3.12 (the higher results) and the lower one obtained using Ecoinvent 3.12 library.

I used the same method (IPCC 2021 ISO 14067) and the same allocation.

I create a new database and then I add the Ecoinvent 3.12 library created by a fresh Ecoinvent 3.12 one.

In the same database I import my model with its parameters and method and finally I perform calculation of product system.

Why there is the difference? Is something wrong in my flow?

Thank you

https://ask.openlca.org/?qa=blob&qa_blobid=9954992828345608931

Answer 1

Do you have no validation errors (right-click database "validate")? Are all your imported foreground processes correctly linked to the same provider from ecoinvent (please click "Check linking properties" and make sure that there is no processes without default provider set)? Is the required amount and the calculated inventory (the total elementary flow results) the same?

Comments

Just take a random ecoinvent process and do the same test. I'm sorry but I can't help for your own processes, where I don't know the details and where you first wrote  that you checked and the provider are correct and then later wrote that there was a different link in the provider.

You can also see in the contribution tree where the difference is coming from. You can see there if the difference is from a flow, from an amount value, from a characterization factor, from a different provider etc.

If nothing works and if the issue is not only with your own processes (that I don't know), you can send a mail with more details on the process. But because you said that "It's the only value out of control (C4: Manutenzione infrastruttura) all the other are ok now.", it is most likely an issue that is related to your own process that you created.