+1 vote
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Hi,

I've been using mainly the Cutoff System Processes version of the Ecoinvent database, but It's not clear to me what are the real diffences between the Cutoff Unit Processes and the System process versions of the database.

In my experience, when using the Unit processes version, the exported Excel file does not contain, e.g. the upstream flow contributions in a simple format, like the one from the System processes version does. I've only managed to export data that basically covers only the LCIs, i.e. only listing elementary flows. Is it possible to get the impacts-per-upstream-process -type of data from the Unit processes version as well?

Another thing I've noticed, is that the export process often freezes in the Unit processes version. I imagine this is due to too large Excel files (because of long lists of elementary flows).

I feel like this is a trivial problem, but I have not been able to find clear explanations for this.

in Miscellaneous by (310 points)

1 Answer

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You can export without the default provider. In case you export something with all default provider in the unit process database, it will export the whole database because nearly everything is linked with everything and this will blow up the export.

Disadvantages for using system processes: no inventories visible, no supply chain visible, no modification for creating new processes possible, no change of input provider possible, no contribution tree of the supply chain visible, no sankey diagram of the supply chain visible, no data quality or uncertainty of the supply chain possible, not really an advantage of calculation speed anymore as it was the case in the past (the newest openLCA is pretty fast also with ecoinvent unit processes and/or libraries), much larger system process database size which makes storage/uploads/backups/copying more time consuming and comes with more storage requirements, searching something in the database or modifying something over SQL is much slower due to the large amounts of exchanges existing, and so on...

I personally would never use the system process version when there is a unit process version available for the exact same data set and the exact same impact results.
by (310 points)
Ok, thank you for the clarification! Now I think I understood :)
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