total upstream impacts

Question

I'd like to automatize the process of generating product system calculations using the olca-ipc python package. The excel with calculations results contains tabs like:

• calculation setup
• inventory
• impacts
• direct inventory contributions
• total upstream inventories
• direct impact contributions
• impact contributions by flow
• total upstream impacts

The only tab I don't know how to recreate is the last one: total upstream impacts. I use olca-ipc 2.4.0 (https://github.com/GreenDelta/olca-ipc.py/tree/v2.4.0) and OpenLCA 2.4. It seems to me that I should use function get_upstream_impacts_of but it produces wrong values for some processes. It also produces many good values which gives me impression that I am close but it's not clear to me what I do wrong that not all of them are correct. Could you tell what's the logic behind the "total upstream impacts" tab, which olca-ipc function should be used to recreate it?

This is the code I use:

import olca_ipc as ipc
import olca_schema as o
from olca_schema import AllocationType

client = ipc.Client(endpoint=<port>)
impact_method = client.find(model_type=o.ImpactMethod, name=<impact category name>)
setup = o.CalculationSetup(
    target=o.Ref(ref_type=o.RefType.ProductSystem, id=<product system id>),
    impact_method=impact_method,
    nw_set=None,
    with_costs=False,
    with_regionalization=False,
    allocation=AllocationType.USE_DEFAULT_ALLOCATION)

result: ipc.Result = client.calculate(setup)
result.wait_until_ready()

impact_categories = result.get_impact_categories()
result.wait_until_ready()

tech_flows = result.get_tech_flows()
result.wait_until_ready()

rows = []
for impact_category in impact_categories:
    for tech_flow in tech_flows:
        items = result.get_upstream_impacts_of(
            impact_category=impact_category,
            path=[tech_flow])
        for item in items:
            row = [
                impact_category.id,
                impact_category.name,
                impact_category.ref_unit,
                item.tech_flow.provider.id,
                item.tech_flow.provider.name,
                item.tech_flow.provider.location,
                item.result,
            ]
            rows.append(row)