Life Cycle Assessment

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Life Cycle Assessment
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Life cycle assessment terminology (ISO 140402006)
Elementary flows (e.g. resource extractions)
input flows
Functional unit
Economy-environment system boundary
economic process
economic process
economic process
economic process
Intermediate flow
Intermediate flow
Intermediate flow
Product system
Elementary flows (e.g. emissions to air) output
flows
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Life Cycle Assessment Framework
Four different phases of LCA are distinguished
Goal and scopedefinition
Interpretation

• Direct application
• product development and improvement
• Strategic planning
• Public policy making
• Marketing
• Other

Inventoryanalysis
Impactassessment
Source ISO 14040
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Goal and scopedefinition
Interpretation
Inventoryanalysis
Impactassessment
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Goal and Scope Definition

• The Goal of the LCA states and justifies
• the aim or objective of the study
• the intended use of the results (application)
• the initiator (and commissioner) of the study
• the practitioner of the study
• the stakeholders of the study (interested
  parties)
• intended users of the study (target audience)
• mention if one objective is comparative
  assertion disclosed to the public

• The Scope of an LCA study defines
• temporal coverage (specific or averaged data)
• spatial coverage (specific or averaged data)
• technology coverage (specific or averaged data)
• coverage of economic processes (initial system
  boundaries)
• coverage of environmental interventions and
  impacts
• mode of analysis (Attributional versus
  Consequential LCA)
• level of sophistication

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Goal and Scope Definition Functional unit and
reference flows

• Definitions
• The functional unit describes the primary
  function(s) fulfilled by a (product) system, and
  indicates how much of this function is to be
  considered in the intended LCA study. It willbe
  used as a basis for selecting one or more
  alternative (product) systems that can provide
  these function(s). The functional unit enables
  different systems to be treated as functionally
  equivalent and allows reference flows to be
  determined for each of them.
• Having defined the functional unit, the amount of
  product which is necessary to fulfill
  thefunction shall be quantified. The result of
  this quantification is the reference flow.
• Issues
• Multi-functionality - Beverage bottles have a
  packaging and an image function
• - Hand drying systems have a drying and a
  hygienic function
• Equivalency of product alternatives is often
  determined by customer acceptance and may be a
  function of price and/or perceived rather than
  real product differences

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Goal and Scope Definition Functional unit and
reference flows
Recommended procedure 1. Identify all relevant
functions of the product system studied 2. Select
one ore more functions as the relevant functions
for the study If more than one function is
relevant - account for primary function only
or - account for primary and (all) additional
functions or - allocate between primary and
additional function (using appropriate mechanism)
3. Specify selected function(s) in (SI or
SI-derived) units 4. Determine an appropriate
quantity 5. Determine and identify the
alternative systems studied in terms of reference
flows
What are functional units for the comparison
of Various paints? Paper versus plastic bags in
supermarkets? What are the resulting reference
flows?
20m2 of wall covering with a coloured surface of
98 opacity and a lifetime of 5 years
Comfortable carrying of X kg and Y m3 of
groceries (what about durability?)
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Goal and scopedefinition
Interpretation
Inventoryanalysis
Impactassessment
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Inventory analysis
In the inventory analysis the elementary flows
associated with the life cycle of the product
system that generates the reference flow are
quantified. These are the material and energy
inputs and waste and emission outputs of all
economic processes that are within the system
boundaries.
Functional unit
Reference flow
Initial flow diagram
Detailed flow diagrams
Unit processes
Inventory table for each unit processes
Aggregate inventory table for reference flow
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Inventory Analysis Initial flow diagram
Definition The flow diagram provides an outline
of all the unit processes to be modeled,
including their interrelationships, which are
intermediate product flows. Starting with an
initial diagram at the level of aggregated
processes for each life cycle stage
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Inventory AnalysisDetailed flow diagram
The initial diagram is followed by detailed
diagrams, at the level of unit processes(processe
s of the system for which individual data are
collected).
Styrene production
naphta gas
styrene
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Inventory Analysis Description of unit processes
Process data
Flow data
Unit process
Intermediate output flows
Intermediate input flows
Elementary input flows
Elementary output flows
Source and collection data
Collector data
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Inventory Analysis Description of unit processes
Process data

• Includes information like
• Function of the process (typically given as its
  economic outputs)
• Name of the process
• Technical description of the process and all
  sub-processes
• Geographical coverage
• Time-period covered
• Technology coverage
• Representativeness

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Inventory Analysis Description of unit processes
Collector data

• Includes information like
• Person or organization that collected the data
• Contact information

Source and collection data

• Includes information like
• Data collections methods (sampling
  measurements techniques)
• Description of models used
• Bibliographic information for secondary data
  sources
• Cut-off criteria and screenings
• Allocation method (if any)

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Inventory Analysis Description of unit processes
Flow data
INPUTS
OUTPUTS
Goods Services Materials Energy Waste (for
treatment)
Goods Services Materials Energy Waste (for
treatment)
Unit Process
Intermediate flows
Intermediate flows
Chemicals to air Chemicals to water Chemicals to
soil Radionuclides Sound Waste heat Casualties Etc
.
Biotic resources Abiotic resources Land
occupation Land transformation Etc.
Elementary flows
Elementary flows
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Inventory Analysis Inventory table
Inputs
Outputs
Example
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Inventory Analysis

• Even though the methodology of inventory analysis
  seems relatively
• straightforward, it is in fact complicated by
  two important issues
• Defining boundaries for the system under
  analysis Which processes to include and which
  to exclude
• Allocation of elementary flows if process has
  more than one economic output

materials energy
wastes emissions
unit process
product A
product B
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Books and Journals

• Some Books on Industrial Ecology (IE)
• IE and Global Change, Socolow et al. (Eds.),
  1994, Cambridge University Press
• Industrial Ecology, Graedel Allenby,1995
  2002, Prentice Hall
• IE Towards Closing the Materials Cycle, Ayres
  Ayres, 1996, Edward Elgar
• IE Policy Framework and Implementation,
  Allenby,1998, Prentice Hall
• Factor Four, von Weizsäcker, Lovins Lovins,
  1998, Kogan Page
• Natural Capitalism, Hawken, Lovins Lovins,
  2000, Back Bay Books
• A Handbook of Industrial Ecology, Ayres Ayres
  (Eds.), 2002, Edward Elgar
• Cradle to Cradle, McDonough Braungart, 2002,
  North Point Press

• Some Journals covering Industrial Ecology
• Journal of Industrial Ecology (e-journal)
• Int. Journal of Life Cycle Assessment
• Journal of Cleaner Production (Science Direct)
• Resources, Conservation and Recycling (Science
  Direct)
• Environmental Science and Technology (e-journal)
• Environmental Toxicology and Chemistry (journal
  of SETAC)
• Ecological Economics (Science Direct)

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Internet resources for LCA http//www.lcacenter
.org/ (American Center for
LCA)http//www.epa.gov/nrmrl/lcaccess/index.html
(EPA website on LCA)http//www.nrel.gov/lci/
(US LCI Database)http//www.uneptie.org/pc
/sustain/lcinitiative/ (UNEP/SETAC life cycle
initiative)http//lca.jrc.ec.europa.eu/lcainfohub
/index.vm (EU website on LCA LCI
database)http//www.ecoinvent.ch (Swiss
centre for LCI data)http//www.netzwerk-lebenszyk
lusdaten.de (German LCA network)
Reading for Thursday, 9 October Ekvall
Finnveden (2001) Allocation in ISO 14041 a
critical review, Journal of Cleaner Production
9(2001) 197-208 Reading available on course
websitehttp//www.bren.ucsb.edu/academics/course
.asp?number282