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Still testing openLCA and have problems with following example:
IMPACT ANALYSIS shows always ZERO.
I did following step by step:

1) New Database -> "new_db" -local (=yes)  -complete reference data (=yes)
2) New process -> "process_metals"
 - create a new flow for the process (as quantitative reference) (=yes)
 -  name of the new flow -> "metal mixture"
 - Reference flow property -> "Number of items"
3)
Inputs:
Elementary Flows > Resource > in ground > Aluminium > 537 g
Elementary Flows > Resource > in ground > Copper > 811 g
Elementary Flows > Resource > in ground > Iron > 398 g
Elementary Flows > Resource > in air > Energy, primary, from solar energy > 2000 KWh
Outputs:
metal_mixture > 1 item
4) Import > other > linked data (JSON-LD) > "openLCA_method_IPCC_2021_AR6_28042022_newcat.zip > finish
5) Close everything > DoubleClick on Process > Tab "Impact analysis" > choose "Impact assessment method" > IPCC 2021 AR6

Doesn't matter what I choose, ZERO all the time with no reference to the process "flows" (Aluminium, Copper, Iron + used Energy) for which I wanted to see the CO2 emissions.

I also tried "openLCA_lcia_v2_0_5_20200610.zolca" with TRACI 2.1, ReCiPe 2016 Midpoint (H), .. with same ZERO results.

What did I miss to consider ?
What do I have to change to get "global warming CO2 eq" results with "Impact analysis" ?
Any general hints what could be improved with this example ?
(don't claim the fictitious values :-)

Many thanks in advance.
I've tried lots of hours during the week-end, but without success unfortunately.
 

in openLCA by (270 points)

1 Answer

+1 vote
by (113k points)
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Best answer
Hi, the first process does not have flows that contribute to climate change, these are all resources. The second (last two pictures) is a different process, a system process (and not a calculation result for a product system). Here, you have some contributions to resource scarcity, so it is not "always zero". If you make a product system of your unit process, the process remains isolated since you do not have any input products in your process. Hope this helps!
by (270 points)
Thanks for your quick reply. Seems it's getting a bit clearer for me now. I have added "Methane" as "Output" of my general process.
And for this I'm getting a result with "IPCC 2021 AR6 / GWP 100" in "Impact analysis" (which is 1.11600E4 kg CO2 eq for 400 Kg Methane) now.
But coming back once again to the example with the metals.
And if I'm just interested in global warming emissions of materials with a certain weight (independent how parts have been made out of the resources) .. Is there a simple way to get this information easily within openLCA ?
I thought I simply could choose a material from "elementary flows", specify the weight and maybe the area where the metals have been mined.
Or - especially for beginners - should they always use an existing proper database and not try to build-up a system completely from scratch on their own ?
So I probably can't proceed without having a licence of a database with which I can access the metals directly and which have values for already mined materials. Is this understood right ? Or at least it will make it much much easier ?
by (113k points)
the elementary flow alone (iron ore in ground) is not sufficient as the GWP emissions of the product (steel) depend on the production (coke-based steel, or steel production using hydrogen e.g.), on the transportation effort, etc., and thus you need to make a life cycle model. Or, take one "pre-fabricated" system process which aggreates a life cycle model result.
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