Normalisation / single score

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Kenza
Posts: 1
Joined: 17 Apr 2012 11:52

Normalisation / single score

Post by Kenza » 21 Apr 2012 15:31

Hello,
I a doing a part of my master thesis with OpenLCA, with Ecoinvent dataset and Impact 2002+ method.
But whenever i want to calculate the results of my product system with an LCIA method I am not allowed to select a normalization / weighting set.
Thus, all my results are in "points" instead of "kg C02 eq" or "DALY"...
Does someone knows how to fix this problem?
Thank you.

aciroth
Posts: 750
Joined: 09 May 2010 23:28

Re: Normalisation / single score

Post by aciroth » 22 Apr 2012 13:11

Hi Kenza,

indeed this looks strange.
openLCA applies normalisation and weighting only if normalisation and weighting sets are available; this is not the case for the default ecoinvent LCIA methods. They rather are provided with weighting and normalisation applied already. Therefore you have e.g. the different ReciPe end- and midpoint methods. This is also true for Impact2002+, with an Impact2002+ (Endpoint) and an Impact2002+ (Midpoint) method. However, for Impact2002+, ecoinvent provides only two midpoint categories, see the screenshot below. This is not incorrect since only these are specific for Impact2002+.

Literature on Impact2002+ states (Jolliet et al, Int J LCA 10 (6) 2003):
1.3 Other midpoint category effects
The characterization factors for the midpoint categories respiratory
effects, photochemical oxidation, ionizing radiation,
ozone layer depletion, terrestrial acidification/nutrification,
land use occupation, and mineral extraction are obtained from
Eco-indicator 99 (Goedkoop and Spriensma 2000), adopting
the default egalitarian scenario and by normalization to a reference
substance. For climate change, the latest IPCC Global
Warming Potentials (IPCC 2001) have been used with a 500
years time horizon to account for long term effects.
So, how to fix this problem? You can on your own integrate these other categories in the XML impact file that you import, copying from the EcoIndicator categories, or perform two separate analyses using EcoIndicator and Impact2002+ which is of course not so convenient.

Hope this helps!
Andreas
Attachments
impact2002midpoint.jpg
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impact2002endpoint.jpg
impact2002endpoint.jpg (153.03 KiB) Viewed 5388 times

mohifalahi
Posts: 7
Joined: 08 Feb 2017 10:58

Re: Normalisation / single score

Post by mohifalahi » 14 Mar 2017 20:31

Dear Andeas,

Thanks for your explanation about reference sources of IMPACT 2002+ LCIA method.
But I have a question. when I use Ecoinvent LCIA method the impact results are in term of "points", i.e. the normalization process is performed already, although I've not selected any normalization method. But when I add OpenLCA LCIA mehtod, and select a normalization method I get the results in terms of reference substances and there is no normalized score. Isn't it paradoxical?
In this situation for having not normalized and normalized impacts, I should perform the calculation 2 times, one time without normalization sets and one time after adding that.

Regards,
Mohammad

aciroth
Posts: 750
Joined: 09 May 2010 23:28

Re: Normalisation / single score

Post by aciroth » 16 Mar 2017 02:57

Dear Mohammad,
I am not sure I understand, in the openLCA package we are not yet providing the impact world+ method, and in the eoinvent package that we distribute the endpoint method has also points, see also the pictures above?
Best wishes,
Andreas

mohifalahi
Posts: 7
Joined: 08 Feb 2017 10:58

Re: Normalisation / single score

Post by mohifalahi » 10 Apr 2017 22:07

Capture.PNG
Capture.PNG (30.1 KiB) Viewed 1760 times
Dear Andreas,
Thank you. but the only problem is that when the OpenLCA LCIA method is not added (so there is no normalization and weighing set), calculating the result (say Eco-indicator 99, (H,A)) leads to normalized scores in terms of points. but when the OpenLCA LCIA method is added, the result is in terms of endpoint reference units like PDF*m2*yr, DALY and MJ. I mean the actions are in reverse of corresponding commands.

Regards,
Mohammad

aciroth
Posts: 750
Joined: 09 May 2010 23:28

Re: Normalisation / single score

Post by aciroth » 11 Apr 2017 21:41

Dear Mohammed,
Ah I think I am getting it now - however, in openLCA 1.6 with method pack 1.5.5, you get a dimensionless value for normalisation results, and points for the single score, see the attachment, so the same as if you apply H,A "in one go" directly. This was your point, right? Thank you for your input!
Best wishes,
Andreas
Attachments
2017-04-11 21_35_56-openLCA 1.6.2.png
2017-04-11 21_35_56-openLCA 1.6.2.png (42.67 KiB) Viewed 1759 times

mohifalahi
Posts: 7
Joined: 08 Feb 2017 10:58

Re: Normalisation / single score

Post by mohifalahi » 04 May 2017 19:28

Dear Andeas,

Sorry but my point was not that. Consider a product system that I want to calculate its effects based on eco-indicator 99 (H/A).
When any normalization set is not added to the software the results are based on points!
When a normalization set is added to the software the results are based on endpoint effects' units (DALY, PDF.m2.year and MJ).

As I know a normalization set converts endpoint effect units to normalized points. but the software shows the results in terms of points when no normalization set is added. As I know it is incorrect based on definition. I use OpenLCA 1.5.0.

Best regards,
Mohammad

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