No impact analysis results gained

Question

I am completing a LCA for a residential house during operational lifetime, I have an array of inputs flows which I am able to link as a product system and an overall energy in the house output flow. However when I calculate results for the overall energy in the house product system it shows as zero for every impact assessment result.

In the flow contributions to process, I can see that all my inputs are registered as upstream incl. direct, however there are no output flow contributions (I think this is why it shows as zero for every impact category for impact analysis)? For my overall energy in the house process I have one output, with defined amount and unit however this seems to produce no results.

Does anyone have any idea why my impact analysis is showing as zero for every category?  Any help is greatly appreciated :)

Answer 1

Hi,

the reason may be that the elementary flows you are using do not have a characterization factor in your LCIA method (And therefor are not compatible). You can check this by double clicking your flow and opening the tab "characterization factors". If this is empty, then this is the reason. (See screenshot -- Here you can see the registered Impact Methods for the flow)

If this is the case, you can open the LCIA method impact category and again open characterization factors. There you will have all the flows that are compatible with your LCIA method.

I hope this helps - and I hope I understood your problem correctly :)