Clara María Mollá Muñoz.PFG_T31

17-July,2013

Practical use of life cycle assessment for

buildings.

1. Introduction.

• Sustainable architecture

The strategies are focused on energy efficiency. Reduce environmental negative impact of the industry.

1. Introduction.• Factors to be setting back the progress towards sustainability.

Lack of information. Financial crisis.

• Economic and ecological efficient product.

• History of LCA. First period: 1970-1990 Decades of conception.

Second period: 1990-2000 Decades of standardization. ISO 14040(2006): Principles and framework.

ISO 14011(2006): Requirements and guidelines.

ISO- “Environmental management” LCA. Widely diverging

approaches. Terminologies. Results.

• Philosophy Cradle to Cradle: Mimic the nature

• What is LCA?

• A technique to assess environmental impacts associated with all the stages of products life.

• Life cycle phases for buildings.

PRE- USE USE

• Raw Materials extraction.

• Processing and manufacturing.

• Transportation.

• Construction.

• Natural gas supply.

• Electricity supply.

• Improvement.

• Maintenance.

END OF LIFE

• Demolition.

• Transport.

• Disposal.

• Recycle.

• Re-use.

• Steps in a LCA.

Step 1.

Goal and scope definition.

• Steps in a LCA.

Step 2.

Inventory analysis.

• Steps in a LCA.

Step 3.

Impact assessment.

• Four sub-steps:

• Category definition.• Classification.• Characterization.• Weighting.

• Steps in a LCA.

Step 4.

Interpretation.

• Environmental impacts.

Global warming potential.

Acidification potential.

• Environmental impacts.

Eutrophication potential.

Fossil fuel depletion.

• Environmental impacts.

Smog formation potential.

Ozone depletion potential.

2. Methodologies and comparing.

Cradle to Cradle.

Extraction raw materials

End of life

Use

Transport and construction

Disposal-Recycle-Re-use

Cradle to Cradle

Cradle to Grave

Pre - use

Manufacture

Cradle to Gate

Gate to Gate: Partial LCA that examines only one value-added process.

2. Methodologies and comparing. Leadership in Energy and Environmental Design (LEED).

Cambridge Engineering Selector (CES): LCA technique.

• Embodied energy.

• CO2 Footprint.

• Energy and water efficient.

• Indoor environmental quality.

• Environmental friendly.

• Sustainable sites.

2. Methodologies and comparing. LEED: evaluates the building altogether.

Cradle to Cradle: evaluates the materials individually.

• LEED & C2C: both are certification.

• Many parameters take into account are irrelevant for this assessment. Is focused in energy efficiency.

• Focused in LCA of the materials, but is a rigid approach to the LCA. “No waste, waste is food”

2. Methodologies and comparing.

• CES & C2C: is concern about the energy used during the manufacturing, re-use and recycling process.

• CES & LEED: evaluation of the impact of the resources used throughout the life of the buildings.

• CES is the most suited for our project.

Embodied energy and CO2 footprint parameters in each phase .

3. Examples of application. Methodology process:

To analyze the LCA of the construction materials.

Two examples: Standard House (SH) and Energy Efficient House (EEH).

Calculating the embodied energy and CO2 footprint of this materials in each phase of building construction.

Calculating the thermal transmittance of the building envelope in both examples and estimate the energy used in the use phase. Compare and evaluate the results of the assessment.

3. Examples of application. Omissions:

• Concrete foundation.• Furniture.(except bathroom)• Municipal services.

• Worker transportation and their CO2 footprint.• The maintenance.• External infrastructure.

EEH major strategies:

• Reduce the embodied energy and CO2 footprint.

•Lowering the life cycle energy consumption.

3. Examples of application.

Aerated concrete blocks

Bamboo

Ecological system window

Plastic tile

Thermic paint

3. Examples of application. Comparing results.

Estructural frameBrich laying

RoofCovering

0

20,000

40,000

60,000

80,000

100,000

120,000

140,000

160,000

TOTAL MASS FOR SH (Kg) TOTAL MASS FOR EEH (Kg)

Life Cycle Mass Assessment:

SH291,6 Tonnes

EEH126,9 Tonnes

EEH reduce approximately 55% of mass.

3. Examples of application. Comparing results. Life Cycle Energy Assessment: embodied energy.• Pre-use and end of life:

Pre-use End Of Life

-500,000

0

500,000

1,000,000

1,500,000

2,000,000

2,500,000

Embodied Energy (MJ) SH Embodied Energy (MJ) EHH

EEH reduce approximately 80% of embodied energy in the pre-use phase.

3. Examples of application. Comparing results. Life Cycle Energy Assessment: Pre-use Transport.

ENERGY (MJ) CO2 footprint (kg)0

5,000

10,000

15,000

20,000

25,000

30,000

35,000

TRANSPORT FOR SH

TRANSPORT FOR EEH

EEH reduce approximately 90% in the energy consumption and CO2 footprint.

ENERGY (MJ)

CO2 footprint (kg)

TRANSPORT FOR SH

30.595,87 2.172,31

TRANSPORT FOR EEH

1.810,52 128,55

3. Examples of application. Comparing results. Life Cycle Energy Assessment:

• Use: thermal transmittance.

• Climatic zone: D3. Navalcarnero (Madrid).

• Façade: Umlimax =0,66 W/m2K

SH = 0,559 W/m2KEEH= 0,339 W/m2K

• Use: energy consumption.

• SH = 37,48 KWh/day

• EEH= 31,58 KWh/day

Use E

nerg

y (K

wh/da

y)

Therm

ic los

s (fa

cing)

(W)

Therm

ic los

s (ro

of) (

W)

0

20

40

60

80

100

120

140

SH

EEH

• Roof:

Uclim = 0,38 W/m2K

SH = 0,378 W/m2KEEH= 0,271 W/m2K

3. Examples of application. Comparing results. Life Cycle Global Warming Potential Assessment:

Pre-use0

50,000

100,000

150,000

200,000

250,000

300,000

CO2 footprint (Kg) SH CO2 footprint (Kg) EHH

End Of Life0

200

400

600

800

1,000

1,200

CO2 footprint (Kg) SH

CO2 footprint (Kg) EHH

EEH reduce approximately 80%-90% of CO2 footprint in the pre-use and end of life phases.

4. Economical impact. Life Cycle Cost Assessment:

0 €

10,000 €

20,000 €

30,000 €

40,000 €

50,000 €

60,000 €

STANDARD HOUSE

ENERGY EF-FICIENT HOUSE

Comparing SH and EEH:

• The traditional materials are cheaper than sustainable materials.

• The EEH are more environmental friendly.

• EEH’s building envelope offers 35% reduction in energy consumption.

• Economize on the building execution of EEH.

5. Conclusions.

We must consider such a product may have relatively good acceptance on the competitive market.

The EEH has obtained a good balance relationship between ecological and economical efficiency.

Total embodied energy Total CO2 fooprint0

500,000

1,000,000

1,500,000

2,000,000

2,500,000

SH

EEH

There’s a difference of 18.000€ in the EEH over SH. But it shown to be an investment on long term.

5. Conclusions.

Standardization

Government + companies of private sector.

5. Conclusions.

“Our goal is a delightfully diverse, safe, healthy and just world, with clean air, clean water, soil and power, economically, equitably, ecologically and elegantly enjoyed, period” William MC Donough.

The best architecture system ever invented The Nature.

Any question?