+4 votes
948 views

Hej,

For a particular project related to food, we are using a food database to do an analysis of procurement. I have been trying to connect to the database using OpenLCA and the Olca Python package with mixed success.

With help from other questions in this forum I have been able to connect, build a product system, calculate the system, and export the results of the many processes I need.

However, when comparing the results from the Olca method to calculation within OpenLCA, the results come out different.

The export from OpenLCA is more in-depth and seems to go a lot deeper than the Olca analysis. There are flows missing in every sheet in the Excel export.

So far I have tried:
1. Using various calculation methods in Olca
2. Different databases to cross-compare
3. Different Impact Assessments

I have seen similar questions but no real answers as to how to retreive the same Excel export from Olca-IPC as one can from OpenLCA, meaning the same level of detail.

You can find my code here.

in openLCA by (160 points)
by (660 points)
Any updates on this issue? I have the same issue. My OpenLCA results make sense and my IPC results are negative for some reason. My product system and calculation setups are identical in both places.
by (160 points)
Unfortunately I have not been able to solve the issue.
This was partly due to time constraints, and we solved it differently now, temporarily.

However, I am also still interested and I hope to pick this up in the future.

I don't know if I remember this correctly but part of the problem could be that writing to Excel gave me an error for using too many rows.

Given the speed at which OpenLCA normally calculates processes and through my code, I assume something else is wrong because the code just flies through only to leave me with 0's everywhere..
by (160 points)
I experience the same issue. I am using the ecoinvent 3.9.1 consequential upr data, OpenLCA 2.0.4 and olca 2.0.2 . I experience this issue with the original electricity processes. I create product systems within openlca and use the specific id to calculate with olca. For all electricity processes I have tested so far, I get different results in OpenLCA ('calculate') and olca. I double checked the impact method. I have the feeling, that olca does not recognize or include all provider contributions.

1 Answer

0 votes
by (1.0k points)

Hi, can you identify/reproduce, how the differences in the underlying inventories (i.e. included flows) are generated?

Are you 100% sure, that you use identical ...

a) ... ways of creating the product systems (provider linking, preferred process type, cut-off)

b) ...  calculation setups (same allocation method)

... in both the openLCA client as well as in olca-ipc?

by (160 points)
To answer this, I have tried every kind of calculation setup, and while there should be a difference, it shouldn't be all zeroes for many of the processes.

Also tried making a product system, that was not the issue.

Thank you for the help though!

I'm still open to other possible solutions
...