1 D r a f t Life Cycle Assessment A product-oriented method for sustainability analysis UNEP LCA Training Kit Module e – Impact assessment

ISO framework Source: ISO D r a f t

3 3 Life cycle impact assessment ISO: Phase of life cycle assessment aimed at understanding and evaluating the magnitude and significance of the potential environmental impacts of a product system –International Standard ISO –Technical Report ISO/TR The third phase of an LCA –LCIA

The principle of characterisation Selection of impact categories, category indicators and characterisation models Classification Characterisation Optional elements –normalisation –grouping –weighting –data quality analysis Contents D r a f t

The principle of characterisation (1) GWP = 1 GWP = 21 impact category category indicator characterisation factor category indicator result D r a f t CO 2 and CH 4 both contribute to climate change Global Warming Potential (GWP): measure for climate change in terms of radiative forcing of a mass-unit of greenhouse gas Example calculation: –5 kg CO 2 –3 kg CH 4 –1 x x 3 = 65 –68 kg CO 2 -eq

6 6 D r a f t The principle of characterisation (2) Simple conversion and aggregation: CO 2 and CH 4 climate change GWP (1 and 21) 5 and 3 kg 68 kg CO 2 -eq infrared radiative forcing IPCC climate model

7 7 D r a f t The principle of characterisation (3) Two main groups of choice for indicator –midpoint-oriented (CML-IA, EDIP, TRACI, …) –endpoint-oriented (Eco-indicator 99, Eco-scarcity, EPS, …) And ongoing efforts to combine/harmonize –midpoint and endpoint (Impact 2002+, Recipe,...)

42 The principle of characterisation (4) D r a f t

The principle of characterisation (5) Structure of endpoint-oriented model (Eco-indicator 99) D r a f t

10 D r a f t Impact categories, category indicators, characterisation models (1) Impact category –ISO definition: class representing environmental issues of concern to which LCI results may be assigned Examples: –climate change –acidification

11 D r a f t Impact categories, category indicators, characterisation models (2) Category indicator: –ISO definition: quantifiable representation of an impact category Examples: –infrared radiative forcing –proton release

12 D r a f t Impact categories, category indicators, characterisation models (3) Characterisation model: –non-ISO definition: mathematical model of the impact of elementary flows with respect to a particular category indicator Examples: –IPCC model for global change –RAINS model for acidifying substances Provides the basis for a characterisation factor

13 D r a f t Impact categories, category indicators, characterisation models (4) Characterisation factor: –ISO definition: factor derived from a characterisation model which is applied to convert the assigned LCI results to the common unit of the category indicator Examples: –GWP –AP

14 D r a f t Impact categories, category indicators, characterisation models (5) Impact categories, characterisation methods and characterisation models: some baseline examples

15 D r a f t Impact categories, category indicators, characterisation models (6) LCA has essentially a flow character: –emissions/ resource extractions in kg per functional unit Impacts have therefore a similar character: –climate change/toxicity/depletion/etc. per functional unit Some impacts do not fit well: –loss of biodiversity/introduction of GMOs/etc.

16 D r a f t Classification (1) ISO definition: assignment of LCI results to impact categories Example: CO 2 and CH 4 are assigned to climate change

17 D r a f t Classification (2) Impact categoryIncandescent lampFluorescent lamp Climate change CO 2 to air kg50000 kg CH 4 to air230 kg24 kg Ecotoxicity Copper to water3 g20 g

18 D r a f t Characterisation (1) ISO definition: calculation of category indicator results Example: 5 kg CO 2 and 3 kg CH 4 yield 68 kg CO 2 -eq

19 D r a f t Characterisation (2) Formula: Unit of characterisation result: –kg CO 2 -eq (climate change) –kg SO 2 -eq (acidification) –…

20 D r a f t Characterisation (3) Example of a characterisation table Impact categoryIncandescent lampFluorescent lamp Climate change kg CO2-eq40000 kg CO2-eq Ecotoxicity320 kg DCB-eq440 kg DCB-eq Acidification45 kg SO2-eq21 kg SO2-eq Depletion of resources0.8 kg antinomy-eq0.3 kg antinomy-eq etc……

21 D r a f t Normalisation (1) ISO definition: calculation of the magnitude of category indicator results to reference information Reference information (over a given period of time): –area (e.g., France, Europe, the world) –person (e.g., a Danish citizen) –product (e.g., the most frequently used product)

22 D r a f t Normalisation (2) Aim: better understand the relative magnitude for each indicator results of the product system under study. –checking for inconsistencies –providing and communicating information on the relative significance of the indicator results –preparing for additional procedures

23 D r a f t Normalisation (3) Formula: Unit of normalisation result: year

24 D r a f t Normalisation (4) Example of a normalisation table Impact categoryIncandescent lampFluorescent lamp Climate change 1.2  yr4  yr Ecotoxicity 1.6  yr2.2  yr Acidification 9  yr4.2  yr Depletion of resources 24  yr9  yr etc……

25 D r a f t Grouping (1) ISO definition: assigning impact categories into one or more sets Sorting: grouping on a nominal basis –e.g., global versus regional Ranking: grouping on an ordinal basis –e.g., high, medium and low priority –based on value choices

26 D r a f t Grouping (2) Example of the results of grouping Impact categoryIncandescent lampFluorescent lamp Global Climate change 1.2  yr4  yr Depletion of resources 24  yr9  yr Regional Acidification 9  yr4.2  yr

27 D r a f t Weighting (1) ISO definition: converting and possibly aggregating indictor results across impact categories using numerical factors –based on value-choices –ISO: “weighting shall not be used for comparative assertions disclosed to the public”

28 D r a f t Weighting (2) Basis for weighting factors: –monetary values willingness-to-pay damage costs reduction costs –distance-to-target methods –panel methods expert panels non-expert panels –...

29 D r a f t Weighting (3) Some methods that include weighting –ecopoints/ecoscaricity –Eco-indicator 99 –EPS

30 D r a f t Weighting (4) Formula: or Unit of weighted index: –year (when based on normalized results) –euro, dollar, etc. (when based on monetary valuation) –but often renamed: ecopoints, millipoints, ELU, etc.

31 D r a f t Weighting (5) Example of the results of weighting Weighed indexIncandescent lampFluorescent lamp Weighted index 8.5  yr1.4  yr

32 D r a f t Data quality analysis Understanding the significance, uncertainty and sensitivity of the LCIA results Suggested techniques: –gravity analysis –uncertainty analysis –sensitivity analysis