Course Introduction - Civil and Environmental Engineering

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Life Cycle Assessment (LCA):
Connections with
Sustainability
Scott Matthews
Green Design Institute
Agenda
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Pre-Assessment
Sustainability’s Place in LCA
Intro to LCA
Links to Sustainability
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This course is 3rd of 4th courses in CEE
“Sustainability” sequence
– Intro to Sustainable Engineering (Fall)
– Industrial Ecology (Fall)
– LCA (Spring)
– Case Studies in Sust. Engineering (Spring)
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Most of you have taken first 1-2 courses
All of you are prepared for this course
Why LCA?
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In “meeting needs of present without
compromising our ability to meet future
needs”, we are faced with some obstacles
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Corporate and social pressures
Governmental/regulatory barriers
Uncertain objectives/goals
Lack of tools to measure our progress
Sometimes our intuition is not a sufficient
framework for analysis
Definitions
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A life cycle of a product (a.k.a. “cradle to grave”)
begins with raw materials production and extends
to manufacture, use, transport, and disposition
LCA is “a technique for assessing the
environmental aspects and potential impacts
associated with a product, process, or system by”:
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Setting goals and scope of study
Compiling an inventory of inputs / outputs
Evaluating potential impacts of those
Interpreting result of the inventory and impact
assessment in context of study objectives
– Suggesting improvements for future benefit
What is LCA?
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LCA is not a cure-all for our
environmental problems
LCA is a way of structuring/organizing
the relevant parts of the life cycle
It is a tool to track performance
Life-Cycle Assessment (LCA)
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A concept and methodology to evaluate the environmental effects of
a product or activity holistically, by analyzing the whole life cycle of a
particular product, process, or activity (U.S. EPA, 1993).
LCA studies analyze the environmental aspects and potential
impacts throughout a product's life cycle (e.g., cradle-to-grave) from
raw material acquisition through production, use and disposal (ISO).
Waste
Waste
Waste
Waste
Mining
Manuf.
Use/
Operation
Disposal
Recycling
Reuse
Reuse
Stages of the Product Life Cycle
Outputs
Inputs
Atmospheric Emissions
Raw Materials Acquisition
Waterborne Wastes
Raw Materials
Manufacturing
Solid Wastes
Use/Reuse/Maintenance
Energy
Coproducts
Recycle/Waste Management
Other Releases
System Boundary
Source: U.S. EPA
Quick Example
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In early 1990s, California had a policy goal of
reducing emissions of air pollution by
encouraging the adoption of ‘zero emission
vehicles (ZEVs)’ into 2% of the fleet by year
1998 (10% in 2003).
– These vehicles were fully battery-powered
– These vehicles had no tailpipes
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A study in Science by Lave et al (1995)
suggested this policy would not achieve its
intended goals
What were the problems?
Example - Answers
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Cars fully powered by batteries
– Batteries of this type need to be recharged
– Recharging happens with electricity
– Electricity production has air emissions!
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Also - at the time, batteries were lead-acid
– Large batteries for battery-only power
– Large amounts of lead needed (with significant
manufacture/recycling emissions of lead)
– More lead released than without ZEVs!
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A Life Cycle Assessment framework if
adopted would have pointed out these issues.
History of LCA
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Note: Life Cycle Cost Analysis is a subset
– Cost focused: big factor in infrastructure management
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Initial LCA work was focused on energy
1969 - first multi-criteria study for Coca-Cola
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Choice between glass and plastic for container
Choice between internal / external container production
End of life options (recycling or one-way)
Result: plastic bottle was best, contrary to expectations.
Study was never published
Questions of validity then occurred
Led to calls by scientific community for a standardisation
process
History (cont.)
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Early 1990s: US Environmental Protection
Agency (EPA), Society for Environmental
Toxicology and Chemistry (SETAC), etc
1997-2000: International Organization for
Standardization (ISO) 14040 documents
– A piece of global “EMS standard”
– First international LCA ‘standard’
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Look over these documents on web site!
Current State of the Art
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Most “LCAs” end at the inventory stage
These studies yield ‘results’ that are a laundry
list of emissions, energy, etc.
The impact assessment stage is still being
developed, validated, and tested globally
Given that, how do we currently translate
these inventories into a practical answer?
Next Class Assignment
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Read First 2 ISO Framework
documents (PDFs) posted on website
– Note #1 is very similar to reading from EPA
(for today) - probably can skim.
– #2 is fairly different
Download