Life Cycle Analysis
Accounting for Sustainability in Existing Buildings
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Building Performance Accounting
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} How do we define and improve energy metrics? } Life cycle analysis(LCA)
Image: Athena Institute
Types of Life Cycles
Embodied Energy
Operational Energy
Definition
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} LCA is a technique to assess the environmental burden associated with a product, process, or service, by: } Compiling an inventory of relevant energy and material inputs
and environmental releases; } Evaluating the potential environmental impacts associated with
identified inputs and releases; } Interpreting the results to help you make a more informed
decision.
Life Cycle Analysis: WHY? To identify environmental ‘hotspots’
acid rain damage air pollution resource depletion water pollution
To assess impacts
Life Cycle Analysis: WHY?
Resource extraction effects
Water use
Emissions to water
Emissions to air
Resource depletion effects
Energy use
Transportation
Solid Waste
Life Cycle Analysis: WHY? To weigh design decisions } Eg. material options
} Local versus regional? } Recyced versus durable?
Life Cycle Analysis: WHY? } There is 275 billion square feet of buildings in the US } Every year 1.75 billion square feet is torn down } Every year 5 billion new square feet is added
Life Cycle Analysis: WHY?
Currently the greatest incentive for the use of LCA is in the ability to improve and demonstrate the “green-ness” of the project and help to increase long-term paybacks by better decision making.
Gwanggyo Green Power Center
Design by MDRDV. Self-sufficient city center for 77,000 in South Korea
} LCA is a way of structuring/organizing the relevant parts of the life cycle
} It is a tool to track performance
Life-Cycle Analysis (LCA)
Major Stages of LCA
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Raw Material Aquisition
Materials Manufacture/ Production
Use/ Maintenance Disposal
Waste Waste Waste Waste
Reuse Recycle Reuse
Conducting a Life Cycle Analysis
1. Scoping: Goal and Scope Definition * Defining your system & its boundaries
2. Inventory Analysis (LCI) * Quantifying material and energy flows throughout the
system – includes embodied energy
3. Impact Assessment (LCIA) * Normalizing inventory data into meaningful impacts within
the world (or your system)
4. Interpretation * Draw conclusions, make recommendations, improve upon
product or process in your LCA
Step 1: Scoping } Define your system.
} What are your goals? What are you comparing?
} A key application of an LCA is to establish a baseline of information on an entire system given current or predicted practices in the manufacture, use, and disposal of the product or category of products.
Step 2: Inventory Analysis Raw material
aquisition
Manufacturing
Products/Assembly
Products/Materials
Recycle/Reuse
Waste Management
Occupancy (use, reuse, maintenance)
Building Construction
Demolition/Disposal
Building Life Cycle Stages
Step 2: Inventory Analysis
Air pollution
Water
Land
Material Resources
Energy
Water
Raw material aquisition
Waste Management
Occupancy (use, reuse, maintenance)
Construction
Demolition/Disposal
Building Life Cycle Stages
Emissions to:
Step 3: Impact Assessment } What does my data mean? How can I add them up or
compare them?
Step 4: Interpretation
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} Interpretation: to help decision-makers make a more informed environmental choices.
} Summary measures: } Global warming potential } Total energy use } Air pollution } Eutrophication
} Increase in chemical nutrients (nitrogen and phosphorus) } Lack of oxygen and severe reductions in water quality, fish, and other
animal populations
} Resouce extraction effects
Tools } Software
} Athena, GABI, SimaPRO, BEES } Economic Input-Output LCA
} www.eiolca.net
} US LCI database
Who is using LCA? } More prevalent in Europe } Some major companies
} Bayer } Coca-Cola } Alcoa } IBM
} Note – carbon footprinting is only one aspect of LCA…LCA captures many more aspects
Relevant Example } Phipps Center for Sustainable Landscapes
} preliminary LCA for the CSL } Used software ATHENA… } Simple model
} Structural steel frame } Masonry load bearing } Precast column and L Beam
} Materials } Cement board siding } Brick } Panel } Polyiso, etc..
Results
Primary energy consump0on (MJ) Solid Waste (kg) Air Pollu0on
Index
Water pollu0on index
Global Warming Poten0al (kg)
Weighted resource use (kg)
Wood 77,183 498 559 13 3,214 24,647
Concrete 1,948,888 33,723 28,808 39 179,806 1,131,118
Instituting/Using LCA } The results can be used to make decisions and evaluate
trade-offs } Comparative analysis
} What wall section
} Most importantly } Can be used for benchmarking } For Phipps CSL
} Can use information to establish where you are and where you want to go
Conclusion
LCA is not a cure all for all environmental problems } For example, LCA does not readily handle such issues as:
} Indoor environmental quality } Improved ability to deal with air quality possible in future
} Uncertainty and risk related to toxic releases } Site specific resource extraction effect
Conclusion } BUT
} It is a scientific method to organize your environmental footprint
} It is one method to assist organizations who want to improve their environmental footprints, ie…work on benchmarking