BYG404-G
Life-cycle assessment of constructions
23.August.2023
LCA in a nutshell 1
1
Today’s readings
• Compendium 1: Chapter.1 – pages 1-20
• Chapter 1 of Hitch Hiker’s Guide to LCA
• Optional: Weidema et al 2004 - The product, functional units
and reference flows in LCA, pages 19-39
Review: seeing things as complex systems - A simple
cake example
Egg
Mel
Sukker
Miksing av
ingredienser
Baking av kaken
Spising av kaken!
Smør
Melk
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A more complete recipe!
Låven til høne
Dyrking av
hønemat
Mat til høne
Dyrking av
sukkerrør
Låven til kua
Dyrking av halm
Høne på gård
Pakking av egg
Kjøling i butikken
Egg
Dyrking av hvete
Knusing av hvete
Holding i butikken
Mel
Miksing av
ingredienser
Koking av rå
sukkerrør
Pakking av sukker
Holding i butikken
Sukker
Smørlaging
Pakking av smør
Kjøling i butikken
Smør
Ku på gård
Melking av kua
Kjøling i butikken
Melk
Baking av kaken
Spising av kaken!
Mat til kua
4
Class exercise – Systems thinking – defining and
describing a system
• How would you describe following systems? What processes
(inputs and outputs to the system) would be included in a life
cycle perspective?
– A house
– An electric car
– The production of steel
– Norway’s energy system
– A road
• What is the purpose (function) of each system?
Newspaper vs. Tablet: Which one has lower
emissions for reading the news?
LCA example: Newspaper
LCA evaluates the
environmental repercussions of
the system
resources into the system
emissions out of the system
http://www.naylornetwork.com/ppi-otw/newsletter.asp?issueID=22315
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Newspaper 2
8
Newspaper 3
9
Newspaper 4
10
Newspaper 5
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Newspaper 6
Why is tablet better
than newspaper?
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What is LCA?
Why, what, and
how to model
Cradle
Beginning of
life
Use phase
Middle of life
Goal and Scope
Definition
Emissions and
resource/energy
inputs
Inventory analysis
Grave
End of life
Environmental
impacts and
characterization
Interpretation
What the
impacts mean
Impact
assessment
LCA framework adapted from ISO 14044/Figure 1.1 in Hitch Hiker’s Guide to LCA
Where do we
get our
materials and
how?
How does
everything get
from one place
to the other?
How do design
choices
influence
impacts?
Cradle
Beginning
of life
to
Grave
End of life
What happens
to our
infrastructure at
the end-of-life?
How are our
materials
processed?
Life cycle of
infrastructure
How are we
building our
infrastructure?
How do we
maintain our
infrastructure?
Life cycle of
infrastructure
Source: Saint Gobain (https://www.isover.co.za/life-cycle-analysis-environmental-product-declarations)
A1
A2
A3
A4
A5
B1
B2
B3
B4
B5
B6
B7
C1
C2
C3
C4
D1
D2
D3
D4
Raw material extraction
Transport
Manufacturing
Transport
Construction and installation process
Use
Maintenance
Repair
Replacement
Refurbishment
Operational energy use
Operational water use
Demolition
Transport
Waste processing
Disposal
Reuse
Recovery
Recycling
Exported energy potental
CEN Standard for system boundaries of infrastructure
System boundaries according to EN15804 and EN15978
Product stage
Construction
stage
Use stage
End-of-life
Benefits and loads beyond the
system boundary
Why do we use LCA?
•
•
•
•
Concern about environmental issues
Need a tool to assess options
To identify improvements in products and systems
LCA useful for making decisions on products (or product
systems) and processes
• Policy, regulations and laws
• To help us understand impacts!
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What do we use LCA for?
•
•
•
•
•
•
•
•
Comparisons of products and systems
Product design/development and product improvement
Strategic planning
Public policy making
Learning/exploration
Communication and Marketing
Ecolabelling
Decision making!
What is an LCA study?
Goal and Scope
Definition
Inventory analysis
Impact
assessment
Interpretation
1. Goal and scope definition
LCA for washing detergent
Purpose
• Perform an inventory of ingredients
• Compare two detergent formulations with environmental impact
• Identify the activities that control the environmental impacts
Q1: What do we mean by environmental impact? Which impacts?
Q2: How much do we include in our evaluation? What is the
boundary?
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2. Inventory analysis
Basic steps in an inventory analysis:
1. Construct a flow model (a flow chart)
2. Collect data
– Raw materials & energy in
– Products out
– Wastes and emissions to air and water
3. Calculate amounts of resource use and emissions and
characterize them as potentials
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Detergent inventory analysis
The inventory analysis maps the
flows in and out of the system
resources into the system
emissions out of the system
Detergent inventory analysis – flowsheet
Material
production 1
Material
production 2
Material
production 3
Material
production 4
Material
production 5
Material
production 6
Material
production 7
Raw
materials
Material
transport 1
Material
transport 2
Material
transport 3
Material
transport 4
Material
transport 5
Material
transport 6
Material
transport 7
Transport
Formulation
Production
Transport to
retailer
Transport
Packaging?
Retail sale
Transport to
user
Surface
water
Water
treatment
Water trp.
to user
Washing
Wastewater
treatment
Retail
Transport
Water & USE
EOL
Inventory analysis
– inventory table
Energy
Resources
Emissions
to air
Emissions
to water
Wastes
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3. Impact assessment
Inventory
results
Emissions
understandable impacts
Weighting
SO2
NOx
HCl
Procedure:
• Classification
• Characterization
• Normalization
• Weighting
Characterisation
results
Acidification
potential
Etc.
NOx
NH3
P
Eutrophication
potential
Single weighted
environmental score
Etc.
CO2
CH4
CFCs
Global warming
potential
Etc.
… other impact categories
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Example: Impact assessment process for GWP
ReCiPe 2016 characterisation methodology
Impact assessment – detergents
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4. Interpretation
• What is the best
option?
• What choice
should be made?
• What can we
improve?
• How can we use
these results?
• How do we
validate the
results?
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