LCA

Question 1

From 1st slide, how is LCA defined?

Answer 1

Cradle-to-grave environmental approach which provides comprehensive view of the environmental impacts of a product or process throughout its life cycle.

Question 2

What does a properly conducted LCA identifies?

Answer 2

It identifies and quantifies potential impacts of an industrial system. It also identifies the potential transfers of environmental impacts from one media to another or from one life cycle stage to another

Question 3

What happens if LCA was not performed?

Answer 3

The trade-offs would not be recognized and properly included in the analysis because it is outside the typical scope or focus of the decision making process

Question 4

History:

1960?

Answer 4

LCA conceived when environmental degradation and limited access to resource start to become a concern

Question 5

History:

1980 and 1990?

Answer 5

Increase in methodological development and international cooperation/collab in the scientific community

Question 6

history:

What about methodological development

Answer 6

Occured mostly in universities. It has continued and increasing attention has been given to international scientific consensus building on central parts of the LCA

Question 7

In 1980’s, the term waste minimization/reduction was defined, what does that represent?

Answer 7

Measures or techniques that reduce the amount of wastes generated during industrial production processes; the term is also applied to recycling or other efforts to reduce the amount of waste goin into the waste stream; Much of the focus remained on recycling and end-of-life activities

Question 8

In 1990, an act was concluded. What is it called, and what does it entail?

Answer 8

Pollution Prevention Act in 1994 defines pollution prevention or clean production which give equal emphasis to activities that reduce potential environmental releases at the source of generation

Question 9

What is source reduction?

Answer 9

Any practice which reduces the amount of hazardous gas, pollutant, or contaminant entering any waste stream or otherwise released in the environment prior to recycling, treatment or disposal. Therefore it reduces the hazards to public health and the environment associated with those releases. It includes modifications to equipment, processes, redesign of products, substitution of raw materials, and improvement on maintenance.

Question 10

What are the life stage of a product, process?

Answer 10

1. Material extraction
2. Material processing
3. Manufacturing
4. Use
5. Waste management after which there can be reuse, remanufacturing or recycling

Question 11

Examples of trade-offs?

Answer 11

Compact fluorescents lights which reduce electricity consumption by 75% but come with a dash of mercury
Biofuels that reduce greenhouse emissions, but affect quality of air, soil, and water at the agricultural stage

Question 12

Why is LCA important?

Answer 12

Tools are needed to help evaluate the comparative potential cradle-to-grave impacts of our actions and ultimately help us prevent such impacts

Question 13

LCA downside?

Answer 13

Although it provides assistance with decision making process, it has limited applicability in that it only helps evaluate the data available at that time only.

Question 14

Importance for engineers and scientists?

Answer 14

Engineers and scientists who develop decision support or make decisions related to sustainability need to understand the need to view the solutions in life cycle perspective. Designers should be able to critically read and evaluate LCA info about alternatives, and the environmental sustainability analyst should be able to perform them

Question 15

Main characteristic of LCA?

Answer 15

• A science-based, comparative analysis and assessment of the environmental impacts of product systems

Question 16

What distinguishes LCA from other environmental analyses?

Answer 16

2 things:

1. The cradle-to-grave analysis
2. Functional unit

Question 17

Core reason for taking LC perspective?

Answer 17

Allows to identify and prevent the burden shifting between the LC stages or processes
Example: substitution of fossil fuels with biofuels reduces impacts on climate change at the use stage but increases climate change impacts from
the harvest and extraction stage

Question 18

What is LCSA?

Answer 18

Life cycle sustainability assessment: encompasses economics and social aspects as well as environmental.
LCSA = LCC + LCA + S-LCA, life cycle cost, and social life cycle assessment

Question 19

4-5 stages of LCA. the structure of the LCA was clearly established…

Answer 19

Clearly established by ISO 14040 in 2006:
1,2. Goal and scope definition
3. LCI, inventory analysis
4. LCIA, life cycle impact assessment
5. Interpretation

Question 20

What is the 5th stage of the LCA?

Answer 20

Interpretation:
results of other phases are considered together and analyzed in the light of uncertainties of the applied data and the assumptions that have been made and documented throughout the study
1. Identify significant issues
2. Completeness check
3. Sensitivity analysis
4. Consistency check
5. Conclusions, limitations and recommendations

Important: due to iterative nature of LCA, important that relevant result aspects mentioned and conclusion aspects drawn must be already stated in the goal or scope

Question 21

What is the fourth stage of LCA?

Answer 21

LCIA - life cycle impact assessment

• Inventory analysis info on elementary flows is translated into environmental impact scores.
• ISO 14040/14044 has mandatory and optional steps

Question 22

What are the mandatory steps of the ISO 14040/14044

Answer 22

• Selection of impact categories/indicators
• Classification - assigning LCI results to impact categories according to their known potential effects
• Characterization - calculating category indicator results

Question 23

What are the optional steps of the ISO 14040/14044

Answer 23

• Normalization (expressing LCIA results relative to those of a reference system)
• Weighting - Prioritizing
• Grouping - aggerating several impact indicators results into groups

Question 24

Choosing LCIA methods

Answer 24

Still in 4th stage, several LCIA methods have been published since the 1st one in 1984

Question 25

What is the third stage of LCA?

Answer 25

Life cycle Inventory Analysis (LCI)

• aims to link all unit processes required to deliver the product studied
• Results in an inventory of the aggregated quantities of elementary flows, separated into resources and emissions, from all the unit processes with the system boundary

Question 26

What is the 1st stage of LCA?

Answer 26

Goal definition:

• clear unambiguous definition of the purpose of the study
• relates to any of the other phases
• Selecting a functional unit

Question 27

What are the 6 aspects of the goal definition (ISO requirements)?

Answer 27

1. Intended applications
2. Limitations due to methodological choices
3. Decision context and reasons for carrying out the study
4. Target audience
5. Comparative studies to be disclosed to the public
6. Commissioner of the study and other influential actors

Question 28

What do the intended applications entail in goal definition?

Answer 28

All LCAs involve studying one or more product systems and this can be used in several applications:

1. Comparing environmental impacts of specific goods or services
2. Identifying the parts of a product system that contribute most to its environmental impact (hot spot indentification)
3. Evaluating improvement potentials from changes in product designs (analysis and what-if scenarios in eco-design)
4. Documenting the environmental performance of product
5. Developing criteria for an eco-label
6. Developing policies that consider environmental aspects

Question 29

What are the 3 types of decision contexts in goal definition?

Answer 29

A (micro-level decision support): Study results are intended to be used to support a decision, but the small scale of the studied system means that regardless of the decision made, it will not cause structural changes in the systems that the studied product system interacts with (individual product studies)
B (meso/maccro-level decision support): Decisions made are expected to cause structural changes in one or more processes of the systems that the studied product system interacts with (policy development)
C (accounting): not intended to support decisions: C1 9includes interactions with other systems and C2 (excludes interactions with other systems)

Question 30

what about target audience in goal definition?

Answer 30

influences the extent to which details of the study should be documented, technical level of reporting and the interpretation of results

Question 31

What about Comparative studies in goal definition?

Answer 31

Should state explicitly if the LCA is of comparative nature

Question 32

What about commissioner of the study nd other influential actors in goal definition?

Answer 32

• ISO standard specifies a number of requirements on the conduct and documentation of the study and an external review process
• Meant to highlight potential conflict of interest
• In comparative studies it may lead to an unintentional bias with data collection

Question 33

What is the second stage of LCA?

Answer 33

Scope definition:

determines what product systems are to be assessed and how it should take place with 9 items.

Question 34

What 9 items does scope definition encompasses?

Answer 34

1. deliverables
2. Object of assessment
3. LCI modelling framework
4. System boundaries and completeness requirement
5. Representativeness of LCI data
6. Preparation of the basis for the impact assessment
7. Special requirements for system comparison
8. Need for critical review
9. Planning reporting of results
   2-6 central pervasive influence on decisions. 1,7-9 mainly communicating the study

Question 35

Terminology and key concepts in scope definition, what are unit process and flows?

Answer 35

-smallest element considered in a life cycle inventory model for which input and output data are required
- input and output data can be organized in 6 categories of physical flows:
input flows : 1–> materials, 2–> energy, 3–> resources
output flows: 4–>products, 5–> waste for treatment, 6–> emissions
output flows belonging to the product or waste to treatment categories from one unit process can act as input flows to the categories materials and energy for other unit process
resources and emission flows are not exchanges between unit processes - they are referred to as elementary flows

Question 36

Terminology and key concepts in scope definition, what are technosphere and ecosphere?

Answer 36

tech: everything fabricated/manufactured but also includes processes that are natural in origin, bt manipulated by humans –> all unit processes of an LCI model
eco: environment/nature –> elementary flows are the only flows that go across between techno and ecospheres

Question 37

Terminology and key concepts in scope definition, what are foreground and background system?

Answer 37

Foreground system: processes of a product system that are specific to it… largely modelled using primary data, i.e. data collected 1st hand by the LCA practitioner
background system: processes not specific to it. modelled using LCI databases, which contain average industry data representing the process in specific nations or regions

Question 38

What are the 2 deliverables in the scope definition stage?

Answer 38

Deliverables are to be compatible with ISO 14040 and an LCA study must include an impact assessment

1. Life cycle inventory (LCI)
2. Life cycle impact assessment (LCI)A results

Question 39

What is the object of assessment in the scope definition stage?

Answer 39

The functional unit:

• For fair and quantitative comparison of alternate ways of providing a function, knowledge of the functions provided by the alternative product systems must be used to define a functional unit
• Defines the qualitative aspects and quantifies the quantitative aspects of the function
• Obligatory and positioning properties (OP are features that the product must possess for any user to perceive it as a product and PP are optional features which can be used to position it as more attractive to the consumer in the competition with other similar products)

Question 40

What is the reference flow is relation to the object of assessment in the scope definition stage of an LCA?

Answer 40

The amount of product needed to realize the functional unit. Typically different qualitatively and quantitavely for different products compared on the basis of a functional unit, due to differences in product properties and characteirstics
A reference flow is the starting point for LCI analysis phase of an LCA

Question 41

Multifunctionality nature of LCI (3rd stage)

Answer 41

• Many industrial processes are multifunctional as in their purpose generally comprises more than a single product or service
• Problem that the product systems under study provide more functions than the one investigated in the functional unit of interest
• no general accepted solution, it is generally recognized that different solutions may considerably influence LCA results depending on the exact position of the multifunctional process in the products flow chart– this is why we do sensitivity analyses, to test influence of different solutions

Question 42

In the context of LCI modelling framework and handling multifunctional processes, what are secondary functions?

Answer 42

Unintended functions that usually have low or now relevance to the users.
Relevant to other systems of the technosphere that the studied product system interacts with
their existence reflects the fact that some processes are multifunctional.
USE ISO 14044 to solve multifunctionality issues tht present a hierarchy of solutions

Question 43

In the context of LCI modelling framework and handling multifunctional processes, how do we proceed for analysis?

Answer 43

Division of unit processes
1st choice is to solve the problem though increasing the resolution of the modelling by dividing the multifunctional unit process into minor units
separate the production of the product from that of the co-product and exclude the subprocesses that provide the additional function
If subdivisions fails to solve the multifunctionality problem, ISO standards recommends system expansion. This means expanding the second process with the most likely alternative way of providing the secondary function of the first process
when system expansion is not feasible, divide the inputs and outputs of the multifunctional process or system between the different products or functions. this can be performed in accordance with the underlying causal physical relationships between the different products or functions. when no common representative parameter can be identified for different outputs, economic relationship is used. Justification for the use of economic allocation is that products are produced due to an incentive of financial income, and that a co-product with market value close to 0 should be allocated a correspondingly low share of the non-product flows

Question 44

In the context of LCI modelling framework, what is attributional modelling?

Answer 44

• represent a product system in isolation from the rest of the technosphere;
• what environmental impact can be attributed to product X?

Question 45

In the context of LCI modelling framework, what is consequential modelling?

Answer 45

Aims to answer the question - what are the environmental consequence of consuming X?

Question 46

In the context of LCI framework, what are system boundaries and completeness requirements?

Answer 46

SB demarcate between the studied product system and (1) the surrounding economy (techno) and (2) environment (ecosphere)
Setting of SB can have a large influence on LCA results as they determine the unit processes from which environmental impacts should be quantified
SB should ideally be set such that all flows crossing them are elementary flows

Question 47

In the context of LCI framework how does representativeness of LCI data work?

Answer 47

• Parts of the foreground system will be based on data collected first-hand by the LCA practitioner.
• Other parts of the foreground system and the background system are constructed from other data sources
• Geographical, technological and time-related representativeness; GR is important as 2 processes delivering the same product output, but taking place in 2 different locations, can be quite different in terms of the other flows (elementary flows, energy flows, material flows and waste to treatment); could be due to local climate and proximity to natural resources, and regulatory differences such as energy taxes and emission thresholds
  TR - due to technological innovation and development,
  -technological Representativeness: 2 identical products can be produces using 2 different technologies and thereby be associated with different unit processes and related flows
• LCA practitioner must use his knowledge about the product system to ensure that it is modelled using unit processes that reflect the actual technologies involved

Question 48

In the context of LCI framework what is the LCI analysis?

Answer 48

It is the most time consuming part of LCA.
During the LCI analysis phase, the collection of data and the modelling of the flows to , from and within the product system is done
the LCI result is a list of quantified elementary flows crossing the system boundary of the studied cycle and it is used as input in the LCIA phase

Question 49

What are the 6 steps of LCI analysis?

Answer 49

1. identifying the processes for the LCI model
2. Planning and collecting data
3. Constructing and quality checking unit processes
4. Constructing LCI model and calculating LCI results
5. Preparing the basis for uncertainty and sensitivity analysis
6. Reporting

Question 50

What does reporting entail in the LCI analysis steps?

Answer 50

Documentation of LCI model @ system level
Documentation of each unit process
Documentation of metadata
Documentation of LCI results
Assumptions of each life cycle stage
Documentation of data collected for uncertainty and sensitivity analysis

Question 51

What is needed for uncertainty and sensitivity analysis?

Answer 51

To enable uncertainty analysis, we must, for quantitative parameters int he foreground system, collect information on their statistical distribution and corresponding statistical parameter values
Sensitivity analysis allows for systematic identification of the parameters that have the highest influence on the LCA results

Question 52

What is entailed in the construction and quality checking of the unit processes? As well as the construction of the LCI model and calculation of LCI results?

Answer 52

When all the unit processes have been constructed or collected from LCI databases, the LCI model can be constructed.
Each unit process can be seen as a “building block” in the LCI model, the “size” of which is ultimately decided by the study’s reference flow derived from the functional unit in the scope definition. LCA software can carry out the scaling automatically, when told what the reference flow is
Compilation of elementary flows over all processes that are part of the LCI model (scaled to the reference model of the functional unit)

Question 53

What is entailed in the planning ad collection of data?

Answer 53

Planning and collection of data. LCI databases are used to source data for the background system and for the parts of the foreground system where more specific data will not be obtained

Question 54

What is entailed in the identification of processes for the LCI model?

Answer 54

Detailing the physical value chain.
The approach to identifying processes is to start with the reference flow and construct the entire foreground system process by process.
Level 0 process: unit process having the reference flow as product output
Level 1: processes required to deliver flows that will be physically embodied in the reference flow
level 2: processes that perform a supporting function of the level 0 process
Level 3: processes required to deliver services
Level 4: processes required to produce and maintain the infrastructure that enables level 0 processes

Question 55

LCI analysis other info?

Answer 55

Process based approach to inventory modelling: LCI using knowledge about the industrial processes taking part in a LC ad the physical flows connecting them.
Environmentally extended input-output analysis (EEIO); top-down approach in inventory modelling: LCI from a macroscale perspective by drawing on a combination of (1) information on elementary flows associated with one unit of economic activity in different sectors and (2) national statistics on the trade of products and services between sectors

Question 56

LCA and decision-making?

Answer 56

Conducting an LCA can help answer a # of important question of concern to decision makers
the goal of an LCA is to not only create data but facilitate decisions. That’s why it is always designed with a specific goal in mind, example to make a product more sustainable.