Mixing databases sources -problem to take into account all the flows in LCIA

Question

Dear all,

I encounter a problem while using different database sources (like ILCD + PEF + Agribalyse) within the same projects. Indeed impact assessment show wrong and underestimated results. The reason is that the flow nomenclature is not the same (different UUID).

My concern is how to merge 2 impact assessment methods (like GWP 100 years from PEF, and GWP 100 years from ELCD) within a same method so that to cover all the flows present in my product system. Can I export two impact assessment methods flows and re-import them within a same method to get that exhaustive coverage (like methane A from A database and methane B from B database with their related characterisation factor without needing to enter all the flows + characterisation factors manually).

Thanks a lot for your help.

Jean-Michel

Answer 1

Hello Jean-Michel,

PEF is a database that is intended to be used as a silo, isolated from everything else. It comes with its own LCIA method that only fits to this database. This is thinking behind the EF (to create one database, with specific elementary flows). Other databases on Nexus don't fit to this database, but for the remaining databases, we try to map the flows to one reference flow system that is in turn recognised and used by the LCIA method pack we provide. There are some exceptions: The IO databases (eora / PSILCA; exiobase) have each an own flow nomenclature; GaBi databases (that we provide for maintenance or to those who have the license and want to use it in openLCA) have their own LCIA method.

It is possible, technically, to merge two LCIA methods of course; if you use an SQL script, that is not too much effort.

All the best,

Andreas