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