brightway-lca / brightway-webapp

🎛️🌿 Template for a Brightway-enabled interactive Web Application based on Panel/Pyodide
http://webapp.brightway.dev/
MIT License
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`cumulative_score` of Depth 2 Inputs does not add up to Total Impact #24

Open michaelweinold opened 5 days ago

michaelweinold commented 5 days ago

For instance, for Automobiles; at manufacturer, all depth 2 (direct inputs into the automobiles manufacturing sector) cumulative emissions are:

Value
4.254063
41.779131
16.025312
8.396221
6.254993
46.7161
9.928445
3.960994
47.036855
11.908974
29.81866
18.014847
7.409095
4.80381
35.368414
18.476232

This sums up to 310.15. But the total emissions are 376. Even with the direct emissions of the automobile manufacturing itself (15), this does not add up.

Screenshot 2024-10-17 at 11 08 36
michaelweinold commented 5 days ago

@cmutel, am I mistaken in believing that direct emissions of the reference product plus cumulative emissions of all direct inputs should sum up to total impact?

cmutel commented 5 days ago

@cmutel, am I mistaken in believing that direct emissions of the reference product plus cumulative emissions of all direct inputs should sum up to total impact?

Are you sure you have all the second tier inputs? The graph traversal will cutoff some smaller scores. My guess is that is the difference. You could also have some self-consumption, not sure about that or where it would matter...

michaelweinold commented 5 days ago

If I have set a cutoff of 1% (like in the above example), can it miss (310+15)-376 ~ 13% of emissions?