LCA

Question 1

Define LCA

Answer 1

Technique for assessing the environmental aspects and potential impacts associated with a product, through:
• Compiling an inventory of relevant inputs and outputs
• Evaluating potential impacts associated with inputs and outputs
• Interpreting results of inventory and impact assessment

Life cycle perspective → Raw material acquisition, production, use and disposal

Question 2

The methodological steps of LCA

Answer 2

1. Goal & Scope definition
2. Inventory analysis
3. Impact assessment
4. Interpretation

Question 3

Describe Goal & scope definition

Answer 3

The goal − Contextual aspects
• Why − reason, intended application
• Who − intended audience 
• What − product/system 
• Purpose − specified question

The scope − Modeling aspects
• Functional unit
• Impact categories − what impacts and how to describe them
• System boundaries and initial flow chart
• Type of LCA and allocation
• Data quality requirements

Procedural aspects
• What actors
• Reporting & critical review

Question 4

Describe the procedure for inventory analysis

Answer 4

1. Construction of flow model
   • Based on initial flow chart (in scope definition)
   • Document as flow chart
2. Data collection
   • Raw materials (including energy)
   • Products
   • Emissions and solid waste
3. Calculation
   • Flows to and from the environment
   • Based on the established functional unit

Question 5

Describe impact assessment

Answer 5

Describe or indicate the impacts of the environmental loads quantified in the inventory analysis. The inventory results are turned into more environmentally relevant information.

1. Classification is made where the inventory parameters are sorted according to the type of environmental impact they contribute to.
2. Characterization is made where the relative contributions of the emissions and resource consumptions to each type of environmental impact are calculated.

The parameters may then be aggregated into a limited number of impact categories. This can be done with formalized and quantitative weighting procedures, expert panels or with qualitative verbal argumentation.

Question 6

Describe interpretation

Answer 6

The information from the first three phases are reviewed.
The elements included in the interpretation can be grouped into three groups; identification of significant issues, evaluation that considers completeness, sensitivity and consistency checks, and conclusions, limitations and recommendations.
The four most critical choices of methodology are the definition of functional unit, system boundaries and allocation procedure, type of data used and impact assessment

Question 7

System boundaries

Answer 7

• System boundaries in relation to natural system
• Geographical boundaries
• Time horizon

•Boundaries within the technical system
(Production capital, Personnel, Cut‐off)

•System boundaries in relation to other product life cycles and allocation

Question 8

Mass allocation

Answer 8

(mass/ sum of all masses) * energy requirement

Question 9

Economic allocation

Answer 9

( (massprice)/sum of all (massprice) ) * energy requirement

Question 10

Weighting and valuation in impact assessment

Answer 10

The impact assessment in LCA can be divided into seven steps.

1. Selection of impact categories, indicators and models.
2. Classification
3. Characterization
4. Normalisation
5. Grouping/ranking
6. Weighting
7. Data quality analysis