Uncertainty values are negative while base value is positive for waste streams (ecoinvent 3.6)

Question

Dear openLCA team,

I recently upgraded to the ecoinvent v. 3.6 and realized that waste flows were moved from the input side to the output side of a process. While the quantity was previously negative on the input side, it is now positive on the output side (which makes perfect sense).

However I realized that the respective uncertainty ranges were not updated, meaning the base value of the uncertainty range remained negative on the output side. As a result the uncertainty ranges do not match the base values. Is this issue known and will it be resolved soonish. Also I do not know whether this is an error in the ecoinvent database or something that happened during the transformation of the ecoinvent database to the oLCA format.

Thank you very much,

Felix

Answer 1

Hi Felix,

this was indeed an issue but we fixed this some time ago and it should be solved with the ecoinvent 3.6 databases we are having now in Nexus.

Best wishes,

Andreas

to your comment: Maybe you did not download the latest version from Nexus, note that with the update we have two versions of ei3.6. I just did a quick Monte Carlo simulation and get this:

Comments

Thank you for your answer Andreas!
I just downloaded the latest version (ecoinvent 3.6 apos, unit processes) and it seems like that issue still seems to be unresolved. One example would be "wind power plant construction, 800kW, moving parts | wind power plant, 800kW, moving parts | APOS, U"

Answer 2

Hello GreenDelta team,

I'm a new OpenLCA user and I bought the ECOINVENT 3.9.1 database. I noticed that for processes that have waste output flows, the value of the geometric mean, present in the uncertainty distribution, is negative. This causes problems in Monte Carlo analysis. Is there a way to work around this problem? There will be updates that will fix this bug.

Thanks for the reply