ESEE 2011, Istanbul

Towards a Green Building Code in Turkey: Lessons from Leadership in Energy and Environmental Design (LEED)

Sonay Aykan

OverviewOutline

1. Overview: LEED, TBEPC and Energy Use

2. LEED and Sustainability

• Defining Sustainability

• Distribution of indicators

3. Assessing Sustainability in LEED

• Assessment methods

• Tools of assessment

4. Turkish Building Energy Performance Code (TBEPC) and energy use

5. Sustainability and assessment in TBEPC

6. Conclusion

OverviewLEED

Leadership in Energy and Environmental Design is an international green building rating system which is widely used in the US.

It has a points systems (110 pts):• Sustainable sites• Energy and Atmosphere• Materials and Resources• Indoor Environmental Quality• Innovation in design • Regional Credits

Main concepts:• Energy conservation• Water use• Health concerns• Users’ effect per unit• Technological fix

OverviewTBEPC

Turkish Building Energy Performance Code is an energy code which regulates the energy certification of the new and existing Turkish buildings.

• Sets limits for the basic energy requirements for buildings.• Energy identities are issued for buildings

OverviewLEED and Energy Use

• In 2006, US Green Building Council (USGBC) conducted a research in corporation with the New Building Institute (NBI) on 121 buildings to determine the energy use in LEED certified buildings.

• Result: LEED certified buildings consume 25-30% less energy per floor area than the national average provided by Commercial Building Energy Consumption Survey (CBECS)

• Biases:1. exclusion of 21 high energy type buildings from the calculations their

average energy use is 154% higher than the US national average

2. use of “building-weighted” calculation method only 13.6% less than the average national energy use

Source: Scofield, J. H. (2009). A Re-examination of the NBI LEED Building Energy Consumption Study. Presented at the 2009 Energy Program Evaluation Conference, Portland

Scofield’s study on energy use in LEED certified buildings

OverviewLEED and Energy Use

Unweighted site energy intensities Weighted site energy intensities

Source: Scofield, J. H. (2009). A Re-examination of the NBI LEED Building Energy Consumption Study. Presented at the 2009 Energy Program Evaluation Conference, Portland

OverviewLEED and Energy Use

Other studies show that if buildings were compared considering their types and their climate zones:

1. LEED certified buildings save 18-35% more energy BUT 28-35% percent of LEED certified buildings use more energy than their counterparts

2. There is no statistically significant relation between LEED certification level and the amount of energy saved. LEED-Silver buildings do not save more energy than LEED-Gold buildings

3. Assessments are based on site energy instead of source energy.

Source:Newsham, G. R., Mancini, S., & Birt, B. J. (2009). Do LEED-certified buildings save energy? Yes, but. Energy and Buildings, 41(8), 897-905.

Sustainability

Sustainability in LEED:

On USGBC’s website LEED’s mission is described to promote “sustainable building and development practices through a suite of rating systems that recognize projects that implement strategies for better environmental and health performance.”(USGBC, 2010).

Source: USGBC. (2010). LEED for New Construction, Introduction. Washington DC: U.S. Green Building Council

SustainabilityDefining Sustainability

• World Commission of Environment and Development (WCED, 1987): “meeting the needs of the present without compromising the ability of future generations to meet their own needs”

• Pelt (1992): A function of current social welfare and the available ecological resources for future generations

• Elkington (1994): a synergetic relationship among economy, ecology and society. Triple Bottom Line

Economy

Ecology

SustainabilityDefining Sustainability

Designing According to the Triple Bottom Line:

• economic performance,

• contribution to employment,

• protection of biodiversity,

• labor processes,

• security,

• public health,

• access to energy,

• access to clean water,

• education

• cultural preservation

SustainabilitySustainability in LEED

0

5

10

15

20

25

30

35

40

Distribution of LEED points (%) Energy gets the most attention from designers. Why?

• In LEED 2009, achieving 40 points is enough to attain a LEED certification.

• There are 35 available points under energy credits

• Energy credits can also lead to achievements in other credits

• Creating buildings that have less operating costs, higher market values

SustainabilityCategorizing Sustainability Indicators

Categories are based on:

• TBL

• Relationship between the daily practices and sustainability

• Strength of this relationship

Ex: In the UN CSD, “proportion of urban population living in slums” addresses this relationship directly through poverty, whereas this relationship is also addressed indirectly through health, governance or land.

• Characteristics of the building industry

SustainabilityComparing Sustainability Indicators

Internationally Accepted Indicator Sets that are examined:

1. Global Reporting Initiative (GRI), 2. United Nations Commission on Sustainable Development (UN CSD)

3. Genuine Progress Indicators (GPI)

4. The Global 100 Most Sustainable Corporations in the World (Global 100)

5. LEED

Basics of Comparison:

• Indicators are placed under categories• Number of indicators that are placed under each category are compared

SustainabilityDistribution of indicators into categories by numbers

SustainabilityDistribution of indicators into categories by percentage

SustainabilityDistribution of indicators into categories by percentage

SustainabilityDistribution of indicators into categories by percentage

Results:• Significant differences between

the distributions

• UN CSD and GRI have more even distributions

• Content of the environment is similar in all indicator sets: Gas emissions, water, biodiversity and energy use

• Contents of the other sectors differ significantly.

Distribution of all the indicators

 

0.05.0

10.015.020.025.030.035.040.045.050.0

EconomyEcologySocial

SustainabilityDistribution of indicators into categories by percentage

For LEED: • 59% Environment• 37% Societal issues• 4 Economy

• LEED’s indicators mostly address locational aspects, water, energy, materials, health and user comfort

• Health issues, User comfort and neighborhood developmen constitute the majority the social indicators

Many social and economic issues that can be related to the building sector are omitted by LEED, including transparency, labor practices, security, access to energy, access to healthy food and education, economic performance and employment.

Assessing SustainabilityTypes of Assessment

Three common methods of assessment :

1. end-user impact assessment

2. lifecycle assessment

3. lifestyle assessment

End-use impact: • Calculation of negative externalities created by the direct actions of the end

users• Externalities (carbon footprint, hazardous gas emissions, waste production,

etc.) are calculated by looking at the consumption processes of goods and services.

Assessing SustainabilityTypes of Assessment

Lifecycle:• Introduced during the UN Earth Summit in Rio in 1992

• Production, transportation and consumption process of products and services

Ex: Evaluating buildings’ CO2 emission requires calculation of CO2 emission that has been created throughout the excavation, production and transportation of the building materials, as well as the CO2 produced by direct use of energy in the building.

• Life cycle assessment method follows a similar path with the “Global Commodity Chain” (GCC) approach

• Source energy, as opposed to site energy, therefore, becomes a means of assessment in the lifecycle method.

Assessing SustainabilityTypes of Assessment

Lifestyle:

• Focus on lifestyles of the users instead of their impacts

• Developed by Lutzenheiser (1992) critique of the mainstream approaches for being limited with technological solutions.

• Energy use in buildings is also affected by the lifestyles and design perspectives

• Diamond’s (2003) research 2020 home-based life style will expand, bigger screen TVs will be introduced, there will be more home appliances to ease the life, work spaces will merge with coffee-shops, air conditioning systems will improve and education will be home-centered

Assessing SustainabilityTypes of Assessment

Future lifestyle:

• Preserving today’s consumption oriented, individualistic vision

• Curbing the externalities of people’s unlimited desires by technological advances

• Less «collective thinking» and less “common good”,

• No proposed solution for fundemental problems such as poverty and inequity They are also the causes of unsustainable production and consumption patterns. (Lele, 2000)

Assessing SustainabilityComparison of assessment methods

Comparison of assessment methods through sample indicators

Means of Assessment Assessment Method

  End User Impact Lifecycle Lifestyle

Site energy use ü ü üEmissions from direct actions ü ü üWaste from direct actions ü ü ü

Source energy ü ü

Emissions from production process ü ü

Waste from production process ü ü

Fair distribution of revenue through commodity chain ü ü

Working conditions in commodity chain ü ü

Promotion of equity in access to resources ü

Promotion of collective desision processed ü

Promotion of conservation policies ü

Formation of social commons ü

Promotion of policies against poverty ü

Assessing SustainabilityAssessment in LEED

• water use• use of material and resources,• construction pollution prevention• heat island effect • low emitting materials• storm water control

Performance of the buildingPerformance of the occupant

(End-User Impact)

Calculations are through per unit area and per unit volume

Technological fixes as solutions

Assessing SustainabilityAssessment in LEED

• 10,000 square feet (929m2).

• The Gores used about 191,000 kilowatt hours in 2006 whereas Nashville household uses about 15,600 kilowatt-hours per year.

• After installation of solar panels, rain water collection systems, solar roof fans and geothermal heating systems. energy consumption of the house decreased only by 11 percent.

• And the house achieved a LEED Gold certification

How so?

• Use of per unit measures instead of aggregate

• Use of technological fixes to obtain points.

Assessing SustainabilityAssessment in LEED

Lifecycle and Lifestyle Assessment in LEED

• certified wood• use of rapidly renewable materials • material reuse• regional materials

• alternative transportation • brownfield development• controllability of lighting systems• reuse of materials• maximization of open spaces

Lifecycle

Lifestyle

It is possible to use Lifecycle and Lifestyle assessment techniques in green building codes.

BUT BOT USED ENOUGH

Turkish Building Energy Performance CodeWhat is it?

• Not an exact equivalent of LEED

• It will define the path towards a green building rating system in Turkey

• It grounds its measures on existing national and international standards such as TS 825, EN 15193, etc.

Turkish Building Energy Performance CodeTBEPC and Energy Use

• No research on the energy use of TBEPC Buildings

Comparison of heat gain/heat loss values for building envelopesConstruction Elements LEED TBEPCSHGC <0.45 NR

Window U Value <U-0.4 0.42 (0.36 for buildings with more than 60% windows)

Ceiling R value R-38 R-20Wall R Value R-18 R-12.5 Floor R Value R-19 R- 25 Basement Wall R value R-9 NRDoors U-0.85 U-0.71

TBEPC’s requirements for a 90 m2 house (TS 825)

LEED Standards for a building in Climate Zone IV

Turkish Building Energy Performance CodeTBEPC and Energy Use

Source: Mehta, P. K. (2001). Reducing the Environmental Impact of Concrete. Concrete International, October 2001, 61-65.

Use of concrete as the default building material in TBEPC challenges with the energy efficiency goals:• Production of cement is among the most energy intensive industries• World’s cement industry accounts for 7 percent of the CO2 emissions • Mining of limestone and clay lead to significant deforestation and loss of top

soil• Its basic fuel, coal, is a significant pollutant• Cement and concrete production use large amounts of freshwater

Turkish Building Energy Performance CodeSustainability and TBEPC (-)

• Sustainability is not stated to be the main goal of TBEPC

• Promotion of use of concrete without any alternative challenges with TBL

philosophy and the synergetic structure of sustainability

• Similar to LEED, TBEPC introduces a technology oriented approach (HVAC

systems, lighting and thermal bridges, etc.)

• Energy and sustainability related design details are missing:

-materials used,

-location and orientation of the building,

-division of inner spaces,

-creation of common spaces

Turkish Building Energy Performance CodeSustainability and TBEPC (+)

• Introduction of a post-occupancy assessment:

the energy ID is given for a period of 10 years.

• Stress on energy efficiency education and

institution of an energy culture in the society

(goals related to lifestyle )

• requirement to install share meters to the

buildings with central heating (Change in

lifestyle)

Turkish Building Energy Performance CodeConclusion

Strategies to carry the building industry to a more sustainable future in Turkey :

• Development of assessment tools to fully address TBL

• Establishment of a synergetic structure

• Regulations on lifecycle of goods and services and lifestyle of users through introduction of necessary indicators.

• Promotion of policies such as fair trade