Life Cycle Assessment

A product-oriented method for sustainability analysis

UNEP LCA Training Kit Module b – Overview of LCA

1

Contents

• • • What is LCA?

Why LCA?

The ISO 14040 framework – Goal and scope definition – Inventory analysis – Impact assessment – Interpretation

What is LCA? (1) • • Officially: L ife C ycle A ssessment Here confined to: quantitative environmental L ife C ycle A ssessment of products – environmental – Life Cycle – Assessment – quantitative – products

What is LCA? (2) • At least three different meanings: – LCA as a field of study – LCA as a technique – LCA as a specific study

What is LCA? (3) • Basically: tool for decision-support – computational aspects • which data • which models • which formulas – procedural aspects • who to involve • how to report • how to use

What is LCA? (4) • ISO-standardised procedure (ISO 14040, created in 1997 2000; revised in 2006) – Structured framework: four phases – Rules, requirements and considerations specified – Specific data and calculation steps not specified – Much attention for transparency in reporting

ISO 14040 framework (1)

Life cycle assessment framework Goal and scope definition Inventory analysis Interpretation Direct applications: Product development and improvement Strategic planning Public policy making Marketing Other Impact assessment

Source: ISO 14040

ISO 14040 framework (2) • ISO: Compilation and evaluation of the inputs, outputs and the potential environmental impacts of a product system throughout its life cycle – International Standard ISO 14040 – complementary International Standards ISO 14041, 14042, 14043 – no Technical Report to 14040, but Technical Reports to 14041 and 14042 – 14044 merges the revised 14040-14043 (2006)

Why LCA? (1) • Why a product-oriented information tool?

– Increased attention for product policy • several national policy plans • EU’s Integrated Product Policy • UNEP’s International Declaration on Cleaner Production • etc.

– Influence consumption and production patterns • clean(er) production • ecolabel • product stewardship • etc.

Why LCA? (2) • Why an integrated information tool?

– Prevent problem shifting • to other life cycle stages • to other substances • to other environmental problems • to other countries • to the future

Why LCA? (3) • Why a method?

– To structure the large amount of complex data – To facilitate comparisons across product alternatives – To enable benchmarking

Why LCA? (4) • Why complex data?

Product property Incandescent lamp power consumption 60 W life span mass mercury content etc 1000 hr 30 g 0 mg … Fluorescent lamp 18 W 5000 hr 540 g 2 mg …

ISO 14040 framework (3)

Life cycle assessment framework Goal and scope definition Inventory analysis Interpretation Direct applications: Product development and improvement Strategic planning Public policy making Marketing Other Impact assessment

Source: ISO 14040

Phase 1: Goal and scope definition (1) • Phase of life cycle assessment in which the aim of the study, and in relation to that, the breadth and depth of the study is established – goal definition – scope definition

Phase 1: Goal and scope definition (2) • Goal definition: – intended application • product development and improvement • strategic planning • public decision making • marketing • other – reasons for carrying out the study – intended audience

Phase 1: Goal and scope definition (3) • Scope definition: – function, functional unit and reference flow – initial choices • system boundaries • data quality • … – critical review and other procedural aspects

Phase 1: Goal and scope definition (4) • Functional unit: – comparison on the basis of an equivalent function – example: 1000 liters of milk packed in glass bottles or packed in carton, instead of 1 glass bottle versus 1 carton

Phase 1: Goal and scope definition (5) • Critical review and other procedural aspects – critical review to ensure the consistency, scientific validity, transparency of the report, etc.

– internal review, external review, review by interested parties – procedural embedding of LCA: LCA as a (participatory) process

Phase 2: Inventory analysis (1) • Phase of life cycle assessment involving the compilation and quantification of inputs and outputs, for a given product system throughout its life cycle • Steps: – preparing for data collection – data collection – calculation procedures – allocation and recycling

Phase 2: Inventory analysis (2) • Central position for unit process – smallest portion of a product system for which data are collected • Typical examples: – electricity production by coal combustion – PVC production – use of a passenger car – recycling of aluminum scrap

Phase 2: Inventory analysis (3) • Data collection for unit processes: – flows of intermediate products or waste for treatment – elementary flows from or to the environment coal generator electricity electricity production fly ash

Phase 2: Inventory analysis (4) equipment steel • Combination of unit processes into a product system • Graphical representation in a flow diagram product system system boundary coal mining generator production coal generator electricity production fly ash electricity reference flow fly ash treatment gypsum

Phase 2: Inventory analysis (5) Source: http://www.fibersource.com/f-tutor/LCA-Page.htm

Phase 2: Inventory analysis (6) • Calculation procedures – relate process data to the functional unit (matrix algebra) – allocation of multiple processes (multiple outputs, multiple inputs, re-use and recycling) coal electricity electricity production with cogeneration of heat (CHP) heat generator fly ash – aggregation over all unit processes in the inventory table

Phase 2: Inventory analysis (7) • Inventory table Elementary flow CO2 to air SO2 to air Copper to water Crude oil from earth etc Incandescent lamp 800000 kg 1000 kg 3 g 37000 kg … Fluorescent lamp 50000 kg 80 kg 20 g 22000 kg …

Phase 3: Impact assessment (1) • Assessment of the importance of the potential environmental effects with the aid of the results of the inventory analysis • Steps: – selection and definition of impact categories, indicators and models – classification – characterisation – normalisation – aggregation and/or weighing

Phase 3: Impact assessment (2)

Life cycle inventory results Example

Cd, CO 2 , NO x , SO 2 , etc.

(kg/functional unit)

Impact category LCI results assigned to impact category Characterisation model Category indicator Environmental relevance Category endpoint(s)

Acidification Acidifying emissions (NO x , SO 2 , etc.

assigned to acidification) Proton release (H + aq) - forest - vegetation - etc.

Phase 3: Impact assessment (3) • Example of a category indicator – Global Warming: Global Warming Potential (GWP): measure for Global Warming in terms of radiative forcing of a mass-unit Example calculation: 5 kg CO 2 (GWP = 1) + 3 kg CH 4 (GWP = 21) = 1 x 5 + 21 x 3 kg CO 2 equivalents) - equivalents (= 68 kg CO 2 –

Phase 3: Impact assessment (4) • Characterisation: • Simple conversion and aggregation of GHGs: IndicatorR esult

cat

 

subs

CharFact

cat

,

subs

 InventoryR esult

subs

GWP (1 and 21) 5 and 3 kg CO 2 , CH 4 68 kg CO 2 -eq climate change IPCC climate model infrared radiative forcing

Phase 3: Impact assessment (5) • Impact categories, characterisation methods and characterisation models: some baseline examples

impact category category indicator characterisation model characterisation factor

abiotic depletion ultimate reserve irt climate change annual use infrared radiative Guinee & Heijungs 95 IPCC model ADP GWP stratospheric ozone depletion human toxicity ecotoxicity (aquatic, terrestrial etc.) photo-oxidant formation acidification ... forcing strat. ozone breakdown PDI/ADI PEC/PNEC trop. ozone formation WMO model Multimedia model, e.g. EUSES, CalTox Multimedia model, e.g. EUSES, CalTox deposition/ac.critical load ... RAINS ... ODP HTP AETP, TETP, etc. UNECE Trajectory model POCP AP ...

Phase 3: Impact assessment (8) Impact category Climate change Ecotoxicity Acidification Depletion of resources etc Incandescent lamp 120000 kg CO2-eq 320 kg DCB-eq 45 kg SO2-eq 0.8 kg antinomy-eq … Fluorescent lamp 40000 kg CO2-eq 440 kg DCB-eq 21 kg SO2-eq 0.3 kg antinomy-eq …

Phase 3: Impact assessment (7) • Impact category results still difficult to understand: – difference in units – difference in scale • Normalisation step to relate the results to a reference value – e.g., total world impacts in 2002 – result often referred to as the normalised environmental profile

Phase 3: Impact assessment (8) Impact category Climate change Ecotoxicity Acidification Depletion of resources etc Incandescent lamp 1.2

 10 -11 yr 1.6

 10 -10 yr 9  10 -11 yr 24  10 -12 yr … Fluorescent lamp 4  10 -12 yr 2.2

 10 -10 yr 4.2

 10 -11 yr 9  10 -13 yr …

Phase 3: Impact assessment (9)

• Even after normalisation no clear answer – aggregation of (normalized) impact category results into a single index – subjective weighting factors needed

Phase 3: Impact assessment (10) • Example of a weighted environmental index Weighed index Incandescent lamp Fluorescent lamp Weighted index 8.5

 10 -10 yr 1.4

 10 -10 yr

Phase 4: Interpretation (1) • Conclusions, recommendations, analysis, all related to goal and scope of the research – among others based on data quality and sensitivity analysis – also: critical review by independent experts

Phase 4: Interpretation (2) • Example of a contribution analysis Process Incandescent lamp Electricity production 88% Copper production Waste disposal Other Total climate change 5% 2% 5% 120000 kg CO2-eq Fluorescent lamp 60% 15% 10% 15% 40000 kg CO2-eq

Phase 4: Interpretation (3) • Example of an uncertainty analysis climate change 160000 140000 120000 100000 80000 60000 40000 20000 0 Incandescent lamp Fluorescent lamp