+1 vote
811 views

I am looking at elementary flows in OpenLCA with the new Ecoinvent 3.9.1. I have noticed that the LCIA for several elementary flows is empty (no characterization factors and therefore no influence on the impact assessment). 

However, I have checked the same elementary flows in SIMAPRO, and they do have characterization factors (even high ones): 

Example: 

In SIMAPRO, for the category Ecotoxicity, Freshwater (EF 3.0 Method), Cadmium oxide-->Air--> unspecified has a factor 33381 CTUe/kg, while no characterization factor is given in OpenLCA for the same elementary flow.

Why this difference? Am I missing something? Should i update the LCIA somehow?

Thanks for your help!

Andrea

in openLCA by (130 points)

2 Answers

+2 votes
by (6.3k points)
Hello Andrea,

You can simply import the openLCA methods package and you will have "Cadmium oxide" characterisation factors for EF 3.0 and EF 3.1. The case before you import the openLCA methods package and cannot find Cadmium oxide/Emission to air/unspecified, simply means that this elementary flow is not used in any ecoinvent process.

The ecoinvent 3.9.1 database that we released comes with the elementary flows (and their corresponding characterisation factors) that are used inside the ecoinvent processes only (for transparency), but it can be (and should be) extended anytime with ca. 60000 elementary flows, having characterisation factors, by importing the openLCA methods package and getting compatibility to some other databases and regionalisation as well.

Having a characterisation factor for a certain elementary flow in the database does not mean that it has an influence on your impact assessment, since this elementary flow also has to be used in a process. Since ecoinvent is not using this elementary flow, I assume that you are modelling a process with direct emission of "Cadmium oxide" into air in one of your own foreground processes. It seems that ecoinvent is always modelling the metal ions and not the oxides in their processes like mining for example. "Cadmium II" is existing in the output of a lot of processes and has a slightly different characterisation factors than "Cadmium oxide" (where I don't know if it is used in any data set).

Best wishes,

Conrad
0 votes
by (3.3k points)
did you find an answer?
by (6.3k points)
see the answer above
...