Life Cycle Assessment (LCA): Connections with Sustainability Scott Matthews Green Design Institute
Agenda Pre-Assessment Sustainability’s Place in LCA Intro to LCA
Pre-Assessment We are doing an assessment of environmental-systems courses at CMU Used to assess literacy before and after Pre-test on your blackboard home page www.cmu.edu/blackboard/ Due Feb 5 (not graded!)
Links to Sustainability 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) Most of you have taken first 1-2 courses Should decide whether to take this, or a similar course (e.g., 12-608)
Why LCA? In “meeting needs of present without compromising our ability to meet future needs”, we are faced with some obstacles 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
Point of Departure: Life Cycle Cost Modeling Developed to track costs over life cycle of infrastructure, etc. Ensure that decision makers thought about “first cost” and maintenance, etc. Useful also for personal decisions (e.g., what kind of car to buy) If you have taken an investment analysis course, this is familiar In depth stuff on this topic better left for a course on Infrastructure Management
Objectives Identify costs that happen during the life of the “project” that are not first cost Determine a “total cost” Compare these to first cost Ideally, “discount” all future costs to the present for comparison Ideally, compare to total benefits to determine whether it is worthwhile
Example - Light Bulbs Should I choose incandescent or flourescent? Bulb costs $1 versus $3 How long are they on? Hours -> kWh -> $ How long do they last? 1000 vs 8000 hrs How much do they “cost to buy & change” E.g., campus laborers cost $40/hr Flourescent bulbs can save lots over life.
Example - A Car What are life cycle costs? Edmunds.com - true cost to own calculator http://www.edmunds.com/apps/cto/CTOintroController Compare 2 cars we are considering. Which is cheaper? Why? Does that change our decision? Is it affected by the type of vehicle (eg sedan)?
Notes on Examples These examples were cost-based, without consideration of environmental issues. Its problems like these that motivated environmental life cycle analysis That is the focus of the rest of the course
Definitions 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”: 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? 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) 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). Mining Disposal Use/ Operation Manuf. Reuse Recycling Waste
History of LCA Note: Life Cycle Cost Analysis is a subset Cost focused: big factor in infrastructure management Initial LCA work was focused on energy 1969 - first multi-criteria study for Coca-Cola 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.) 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’ Look over these documents on web site!
Stages of the Product Life Cycle Source: U.S. EPA
Quick Example 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 A study in Science by Lave et al (1995) suggested this policy would not achieve its intended goals What were the problems?
Example - Answers Cars fully powered by batteries Batteries of this type need to be recharged Recharging happens with electricity Electricity production has air emissions! 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! A Life Cycle Assessment framework if adopted may have pointed out these issues.
Anecdote Studies on “green” buildings suggest that a 2% increase in initial cost can save 10x This is only the dollar-based benefit
Current State of the Art 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?
Re-linking cost and environment This is a course on sustainability Different definitions, but in general it refers to economic, social, and environmental issues being jointly considered Cost (economic) is only one part. We need to understand the others also. LCA is the kind of tool to help do this. Goal: life cycle THINKING.
For Next Class Read US EPA Intro to LCA Read the 2 ISO Framework documents (PDFs) posted on website Note #1 is very similar to reading from EPA - probably can skim. #2 is fairly different In class we will do a visual learning exercise to motivate why life cycle assessment matters
Pre-Assessment Reminder Don’t forget to do the blackboard Assessment Under course “S07 Environmental Assessment”