LCA

Question 1

What is Life Cycle Assessment (LCA)?

Answer 1

• A method to assess potential environmental impacts over the life cycle of products and services according to ISO 14040/44
• ISO14040/44 is the only standardized method to assess potential environmental
  impacts of products and services along its entire life cycle

Question 2

Environmental impacts

Answer 2

• Climate change
• Acidification
• Eutrophication
• Ozone layer depletion
• Etc.

Question 3

Why LCA?

Answer 3

LCA can assist in:
* Determining the potential environmental impacts of a product
* Comparing the environmental performance of products
* Identifying (hidden) environmental hotspots of a product (life cycles, processes)
* Identifying options for environmental improvement in different stages along a product’s life cycle (assist eco design)
* Informing decision makers in industry, government, NGOs, etc.
* Marketing (e.g. in the implementation of eco-labels, in making environmental claims, in environmental product declarations)

Question 4

Limit of LCA

Answer 4

• LCA is able to:
  – Determine the relative impacts of a product not the absolute ones
  – Cannot determine the real impacts of a product, only the potential ones
  – Cannot compare products with different functions
  – Cannot give universal statements with regard to materials
  – Cannot assess social aspects or risks
• LCA depends on:
  – Data quality
  – Time
• LCA does not deliver:
  – Binary results: yes/no; black/white and can therefore only support decisions
  – ONE combined result but many results for different impact categories

Question 5

LCA use ‒ recent developments

Answer 5

There is an increasing use of LCA in market and policy!
* LCA is widely used in companies;
mainly internally for product- and process optimization,
but increasingly also for external communication
* Transparent supply chains become more and more important for companies
* In policy, LCA is increasingly used, e.g. as basis for environmental labels
* In the EU the Product Environmental Footprint (PEF), a current initiative
for implementing LCA, which gains a lot of attention
* Besides this, many other options for LCA deployment in policy exist

Question 6

Methodological framework ISO 14040/44

Answer 6

• ISO 14040/44 is the only standardized
  method to assess potential environmental
  impacts of products and services along its
  entire life cycle
• An LCA based on ISO
  14040/44 consists of
  4 phases:
  1. Goal&Scope definition
  2. Inventory Analysis
  3. Impact assessment
  4. Interpretation

Question 7

LCA phase 1: goal & scope definition
Goal definition

Answer 7

– Target of the LCA
– The reasons for conducting the LCA
* e.g. learn about environmental impacts; identify improvement potentials
– The target audience
* e.g. for internal use only or to communicate to consumers
– Whether the LCA contains comparative assertions disclosed to the public

Question 8

LCA phase 1: goal & scope definition
Scope definition

Answer 8

– The description of product system and its functions
– The functional unit and reference flows
– The system boundaries and cut-off criteria
– The data requirements
– The allocation procedure
– The impact categories and characterization models
– The assumptions and limitations
– Type of critical review (if any)
– Type and structure of report

Question 9

LCA phase 1: goal & scope definition
Function

Answer 9

Must define:
* Specify the functions (performance characteristics) of the system
– Functional unit as defined by [ISO 14044]:
* quantified performance of a product system for use as a reference unit (e.g. drying 1000 pair of hand)
* shall be clearly defined and measurable
– Reference flow as defined by [ISO 14044]:
* measure of the outputs from processes in a given product system required to fulfil the function expressed by the functional unit (e.g. 20 cotton towls, 2000 paper towls, 500 m³ of hot air)

Question 10

LCA phase 1: goal & scope definition
System boundaries

Answer 10

• Defines which life cycle phases and which process steps are included in the analysis
• Process: smallest element considered for which input & output data are quantified (e.g. extraction of aluminium oxide/hydroxide from the ore)

Question 11

LCA phase 1: goal & scope definition
Cut-off criteria

Answer 11

Criteria which allow to neglect flows or processes within the system boundaries
* Aims:
– Ensure applicability of LCAs by minimizing efforts
– Ensure symmetry within product systems
– Ensure symmetry between product systems to ensure comparability
– Estimate relevance of auxiliary products
* Types of cut-off criteria:
– Number of system levels, e.g. only direct production and tier 1 suppliers
– Mass- or energy based cut-off criteria, e.g. 3% of the product’s mass
– Impact based cut-off criteria, e.g. 5% of result

Question 12

LCA phase 1: goal & scope definition
Data requirements

Answer 12

• Primary data
  – Directly measured or collected company data
• Secondary data
  – Literature
  – Other LCA studies
  – LCA databases
• Calculations
• Estimations
• Scope of data:
  – Spatial scope, e.g. only European data
  – Temporal scope, e.g. not older than 2010
  – Technological scope, e.g. average of processes or best available technology

Question 13

LCA phase 1: goal & scope definition
Impact categories

Answer 13

• Definition which impact categories are relevant and shall be analyzed;
  common impact categories are:
  – Primary energy demand; consumption of energy carriers
  – Climate change: Contribution to global warming
  – Acidification: Contribution to acidification of soil and water
  – Eutrophication: Contribution to over-fertilization of soil and water bodies
  – Summer smog: Contribution to chemical ozone creation
  – Human toxicity: Contribution to human toxic impacts
  – Eco toxicity: Contribution to eco toxic impacts
  – Etc.
• Besides the selection of impact categories, characterization models have
  to be selected based on which impact category results can be determined,
  e.g.: CML, ReCiPe, Traci, etc.

Question 14

LCA phase 1: goal & scope definition
Scope definition

Answer 14

• The scope should be defined in a way that it allows for reaching the defined goal of the study
• As LCA is an iterative procedure, it may be necessary to modify the scope during the course of the LCA study (data availability)

Question 15

LCA phase 2: life cycle inventory (LCI)

Answer 15

• All material flows entering and leaving the product system are compiled in an inventory (Input / Output Table)
• In and outputs shall be traced back to resource extraction from the environment and emissions into the environment (elementary flows)

Question 16

LCA phase 2: life cycle inventory (LCI)
Steps in the life cycle inventory analysis

Answer 16

Qualitative life cycle inventory analysis
* Determination of type of environmental interferences along the product’s life span
* Qualitative description of the In- and Outputs occurring in the different processes in a flow chart
* Definition of consistent terminology for In- and Outputs and units
* Development of data acquisition sheets
* Description of type of data acquisition
* Definition of calculation procedures relating data to functional unit

Quantification
* Data acquisition in count- and measurable units
* Data validation (Differentiation between “real” zero or lack of data, analysis of abnormalities),
* Normalization of process data to its function (e.g. operating hours, cleaned surface, etc.)
* Normalization of data to functional unit
* Documentation of data sources, measurements, etc.
* If there are by-products, in- and outputs need to be allocated between the main and the by products

Question 17

LCA phase 2: life cycle inventory (LCI)
Data sources

Answer 17

Data can be collected according to the following hierarchy:
1) Primary data sources: collected directly at the company, e.g. own measurements
* Measurements (if possible continuous)
* Invoices
* Process control systems
* Approval documents
* Emission declarations and monitoring of facilities requiring a license
* Waste balances and records of waste disposal
* Company internal quality and environmental management
* Environmental declaration and reports
* Health and safety systems
* Etc.
2) Secondary data sources:
* LCA databases
* Literature
* Previous studies
* Etc.
3) Calculations:
* Physical calculations, e.g. energy demand to heat up a material
* Chemical calculations, e.g. determination of emissions based on stoichiometric
relations
4) Estimations

Question 18

LCA phase 2: life cycle inventory (LCI)
Databases and software

Answer 18

Databases: Gabi-Database, Ecoinvent
Software: Gabi, SimaPro, Umberto, OpenLCA

Question 19

LCA phase 2: life cycle inventory (LCI)
Allocation

Answer 19

Often one process produces more than 1 products
* Question: How to distribute the environmental burden between products?

How deal with allocation?
1. Avoid allocation due to:
– Detailing into subsystems, e.g.: allocation of a company’s total emissions to different products can be avoided if individual production routes are considered separately
– System expansion, e.g. allocation between the products steel and slag can be avoided, if it is assumed that slag substitutes sand in road construction. Emissions of sand production can be subtracted from total emissions of steel/slag production to determine environmental load of steel production
2. Allocation based on physical properties
– Example: Distribution of a refinery’s environmental burden to its products based on mass or energy shares
3. Allocation based on different (e.g. economic) relations
– Example: Distribution of environmental burdens caused by a copper-gold
-zinc mine based on market values. This makes more sense than a mass based allocation in which 1 kg of zinc would have the same environmental burden as 1 kg of gold

• Allocation principle: The sum of in and outputs has to be the same before and after the allocation
• If the choice of the allocation procedure influences the result of the LCA, this should be made transparent by means of a sensitivity analysis

Question 20

LCA phase 2: life cycle inventory (LCI)
Recycling

Answer 20

Principle of first responsibility vs. Principle of last responsibility:

• Recycling in LCA requires the distribution of environmental burdens resulting
  from primary production, recycling processes, and disposal
   Allocation between life cycles
• There is no right or wrong – decisions are based on value choices:
  – Conservative: Principle of first responsibility – environmental burden of primary
  production is fully allocated to the first life cycle and cannot be “lost”
  – Risk-oriented: Principle of last responsibility – environmental burden of primary
  production is shifted to the last life cycle. There is a danger that environmental
  burden is “lost”, if the last life cycle uses a first responsibility allocation.
  – Compromise: Equality approach, economic allocation, discounting, approach, etc. –
  environmental burden is allocated between all life cycles
• There are no right or wrong but adequate or inadequate solutions, e.g.:
  – In order to apply the equality approach, the number of life cycles has to be known –
  works out for PET bottles but not for cars
  – Principle of first responsibility may be too conservative for reusable bottles
  – Quality based allocation may be appropriate for alluminium products to consider
  downcycling
• If the choice of the allocation procedure influences the result of the LCA, this
  should be made transparent by means of a sensitivity analysis

Question 21

LCA phase 3: life cycle impact assessment (LCIA)

Answer 21

• In the life cycle impact assessment, in and output flows complied in the life cycle inventory are “translated” into environmental impacts

…provide information to help assess a product system’s LCI results so as to better understand their environmental significance…

• to determine potential environmental impacts for a product system

Question 22

LCA phase 3: life cycle impact assessment (LCIA)
Impact categories

Answer 22

Class representing environmental issues of concern to which LCI analysis results may be assigned
* Climate change
* Acidification
* etc.

Question 23

LCA phase 3: life cycle impact assessment (LCIA)
Classification

Answer 23

The in and output flows compiled in the life cycle inventory (resources, emissions, etc.) are assigned to environmental impact categories

In the classification there are three groups of LCI results:
1. Elementary flows, which contribute to no impact category
2. Elementary flows, which contribute to exactly one impact category
3. Elementary flows, which contribute to different impact categories

Question 24

LCA phase 3: life cycle impact assessment (LCIA)
Characterization

Answer 24

• Multiplication of each emission (LCI) with a characterization factor (CF)
• CF = individual contribution of the emission to the environmental impact

Question 25

LCA phase 3: life cycle impact assessment (LCIA)
Problems in LCIA

Answer 25

• Characterization can lead to clear results (one product causes less impacts in
  all impact categories) or
• Characterization often leads to contradictory results (Product A causes less
  impacts in climate change, acidification, and human toxicity. Product B causes
  less impacts in resource depletion, eutrophication, and eco toxicity)
• Optional elements can help to reach a general conclusion:
  – Normalization (impact category for a reference, e.g. for a region)
  – Grouping incl. Ranking (classification of impact categories base on value choices, e.g. high/middle/low priority)
  – Weighting (impact category are mutiplied by weighting factor to aagregate a singel-score result)

Question 26

LCA phase 3: life cycle impact assessment (LCIA)
Mid-point vs. End-point

Answer 26

• Impact categories and characterization models can be defined in the middle or
  at the end of a cause-effect chain
• Mid-point: scientifically valid but rather abstract
  e.g.: global warming potential, CO2-equivalents
• End-point: high uncertainties, but more meaningful as damages are predicted
  e.g.: loss of human health, disability adjusted life years (DALY)
• Various mid-point impact categories can be aggregated in few end-point
  impact categories (human health, ecosystem, resources)
• Examples for end-point models: Ecoindicator 99, ReCiPe, LIME, Impact World+

Question 27

LCA phase 4: interpretation

Answer 27

Identification of significant issues:
* Particularly critical environmental impacts
* Significant processes, which dominate the result of one or more impact categories
* Assumptions which strongly influence the results:

Question 28

LCA phase 4: interpretation
Critical evaluation of previous steps

Answer 28

• Goal and scope definition
  – „Validation rule“ for interpretation: Is the study in line with the requirements
  defined in the goal and scope definition
  – Have the functional unit and reference flows been chosen adequately?
  – Have system boundaries been set appropriately?
• Life cycle inventory
  – How do achieved data quality and data gaps influence the results?
  – How do assumptions in the LCI modeling influence the results?
• Life cycle impact assessment
  – Which impact categories have been excluded?
  – How do limitations of the impact assessment influence the conclusions?

Question 29

LCA phase 4: interpretation
Evaluation of significant issues

Answer 29

• Completeness check
• Consistency check:
  – Are assumptions, methods, and data in line with the requirements specified in
  the goal and scope definition?
  – Are assumptions, methods, and data applied symmetrically?
• Sensitivity check
  – Aim: Quantitative assessments of the influence of assumptions such as allocation
  procedures, cut-off criteria, data choices, modeling assumptions, etc.
  – Procedure: By altering the significant issue the influence of this alteration on the
  total result is analyzed

Question 30

LCA phase 4: interpretation
results

Answer 30

• Result analysis (based on LCI and LCIA)
• Conclusions and recommendations
• Limitations
• Transparent report