+1 vote
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In the model graph, it is possible to connect processes downstream from the process which is used as referece flow. However, these processes were not considered in tec-matrix I built from this product system. is there a way to include these processes in the tec-matrix?

in openLCA by (280 points)

1 Answer

+1 vote
by (14.0k points)

Right, starting from the reference process the linked processes of product inputs and waste outputs are recursively included. So only downstream waste treatment processes are considered but not downstream product consumers.

To solve this, you could add an additional process to your product system and link the downstream product consumers as providers to that new process. Then, you set this new process as reference process of your system. However, you need to carefully check the links in the resulting system to avoid double counting. A link to a process always means "include that process (and its supply chain) with the linked amount".

Same example as in this allocation question:

Say your current reference process is `p1` and you have two downstream consumer processes `p2` and `p3`. You would add a process `p4` that links to `p2` and `p3` in its inputs and then set `p4` as the reference process of the system. To avoid double counting you could set allocation factors in `p1` are delete one of the links to `p2` or `p3`.

by (280 points)
Perfect, thank you. Just one more question: You advised to "set this new process as reference process of your system". Do I do this by building a new product system from p4 or is it possible to change the reference process within a existing product system?
by (14.0k points)
Oh, I see... it was possible in earlier openLCA versions to change the reference process of a product system but in the current version you have to build a new product system.
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