Recently, I downloaded and imported the latest version of USLCI from their Github website along with the three available LCIA methods.
However, when I created simple processes and product systems to evaluate the environmental impacts of two PET (Polyethylene terephthalate) pellets included, the project report showed all the environmental impacts as negative. I have tryied to import different format of USLCI (JSON-LD or zolca) and changing LCIA methods, but none of them worked.
Additionally, the environmental impacts of product systems were positive when calculated directly. Once calculated in the project, a large negative contribution appeared in the last row of result contribution.
I am currently confused and unable to identify the cause of this issue. Any advice would be greatly appreciated. Thank you very much!