Energy Performance of Courtyard and Atrium in Different Climates-libre

8/11/2019 Energy Performance of Courtyard and Atrium in Different Climates-libre

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Energy Performance of Courtyard

and Atrium in Different Climates

MSc Renewable Energy and Architecture

Research Methodologies

K14RMS

Ahmed Qadir Ahmed

2013


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List of contents

Abstract 1

1. Introduction 1

2. Functions of courtyard and atrium in buildings 2

2.1. Courtyard 2

2.2. Atrium 3

3. Methodology 5

4. Results of annual energy consumption 7

5. Discussion of the results and conclusion 9

6. Research challenges and suggestions for future research 11

References list 12

Appendices 14

List of figures

Figure 1: The courtyards effect on ventilation during days and nights 3

Figure 2: Environmental benefits of an atrium (Baker and Steemers, 2005) 4

Figure 3: The models of courtyard and atrium buildings fir the simulation 6

Figure 4: World map of Koppen-Geiger climate classification 6

Figure 5: Annual heating and cooling energy demand for the model in Riyadh 7

Figure 6: Annual heating and cooling energy demand for the model in Bangkok 8

Figure 7: Annual heating and cooling energy demand for the model in London 8

Figure 8: Annual heating and cooling energy demand for the model in Moscow 9

Figure 9: Annual heating and cooling energy demand for the model in Tehran 9

Figure 10: Monthly average outdoor temperature in selected cities (source: weatherdata of EnergyPlus)

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List of tables

Table 1: Total Annual energy demand for all models 14


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2. Functions of courtyard and atrium in buildings

There are many types of architectural zones which moderates the outdoor and indoor climatic

conditions without mechanical control systems. These zones are called transitional spaces.

They can be closed such as atrium or semi closed such as balcony and porch or open such as

courtyard and patio (Taleghani et al., 2012b). This research focuses on the environmental role

of both courtyard and atrium in buildings in different climates. Different aspects of both are

explained following.

2.1. Courtyard

There are different definitions of courtyard. According to the Oxford Dictionary, courtyard is

an unroofed area that is completely or partially enclosed by walls or buildings, typically one

forming part of a castle or large house. In the past it was used as a traditional element

especially in designing the houses. Recently, it is considered as one of the passive design

strategies to moderate the climatic conditions (Heidari, 2000).

In many regions courtyard is an important and popular architectural space because it involves

many daily activities due to its characteristics. For example, it is a safe place for playing of

children or womens activity especially in the third world countries. Moreover, It can be used as

a pray place in mosques or as a gathering place in schools, hospital, commercial buildings and

even in prisons. Therefore, the courtyardsfunction is one of the factors to decide on its using

as well as its shape and size (Taleghani et al., 2012b).

One of the main reasons of using courtyard for more than 5000 years is its environmental

effects. In different climates, courtyard can be used as a source of day-lighting for adjacent

rooms in deep plans. Further advantage of courtyard in winters is protecting the parent

building from harsh conditions of weather such as winds (Upadhyay, 2008). During cold

seasons it may increases direct solar heat gain in the rooms which have glazing area on the

courtyard. Its performance during summers is different. It can be a solar protector by planting

deciduous trees in the courtyard. Furthermore, natural ventilation during hot seasons occurs

through the courtyard especially in hot climates. During daytime the air in the courtyard

becomes warmer and rises. This draws out the internal warm air into the courtyard through

the openings. Consequently, it makes an air movement inside the adjacent building. Duringnights the process is opposite in which the ambient cool air sinks into the courtyard and enters

into the internal spaces through the low-level openings. This makes airflows in the rooms and

the cooled air becomes warm and then it rises and leaves the rooms through the high-level

openings (figure 1) (HPCB, n.d.). Bahbudi et al. (2010) point out that the courtyard can be

more effective for natural evaporative cooling with the help of vegetation and fountains.

Moreover, the shady area can be increased by the high walls around the courtyard and this

reduces the temperature of the ground surface. As a result, the courtyard can be used during

the daytime.


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building walls and providing pre-heated ventilation. Consequently, the heating energy demand

of the parent building decreases. In summers, preventing overheating is the main problem

which should be eliminated. Usually, the indoor air temperature in summers is higher than

ambient temperature. The first action to prevent the indoor air temperature from increasing is

shading. There are different shading devices in atriums. They may be fixed which reduces solar

radiation all over years or may be moveable to eliminate solar radiation only in overheating

periods. They also decreases glare inside the atrium and inside the rooms. The second action is

providing natural ventilation. It can be achieved by creating adequate area of openings in

suitable places especially in upper and lower levels of atrium to provide cross and displacement

ventilation. Furthermore, using thermal mass material in internal surfaces can absorb heating

energy during the daytime and release it during the night when air temperature decreases. In

addition, planting and fountains can moderate indoor environment during the whole year

(figure 2) (Baker and Steemers, 2005, Goulding et al., 1993 and Douvlou, 2004).

Figure 2: Environmental benefits of an atrium (Baker and Steemers, 2005)

Based on the different relevant studies, main ideas of both courtyard and atrium performance

have been generally examined. Most of the information in the studies is mainly about the

general architectural and environmental aspects of transitional spaces. There is not sufficientknowledge about to what extent both spaces affect the building energy consumption in

different climates. Both studies Taleghani et al. (2012a) and Aldawoud and Clark (2007) are

the the studies, which are based on computer simulations, deal with the performance of

transitional spaces in different climates. However, the selected climates cannot represent all

regions throughout the world. For example, cold-arid climate is not used in simulations and

there are not results for this region. Moreover, there is not a clear decision about which one of

the courtyard and atrium is more energy conscious in certain climates.


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3. Methodology

From the literature review it can be pointed out that the most important environmental

purposes of using courtyard and atrium are to enhance day-lighting and reduce the heat loss

in cold seasons and heat gain in hot seasons in the parent building. These cause decreasing of

annual lighting, heating and cooling energy demand (Ger et al., 2006, Baker and Steemers,

2005 and Goulding et al., 1993). These extracted statements from the relevant literatures can

be used as the research hypothesis and apply it to the research methodology. This research

paradigm is pragmatism which is extracting theory or hypothesis from practice or literature

review and applying back the theory to practice (computer simulation in this research).

Pragmatism paradigm leads to reliable findings and achieve better answer for the research

question (Rescher, 2012 and Hogue, 2011).

In the research methodology, building energy demand is used as the most appropriate

parameter to examine the environmental effects of courtyard and atrium on their adjacent

buildings. In other words, by comparing the annual energy demand of courtyard and atrium

buildings can indicate which one is more appropriate for different climates by knowing that

which one leads to less annual energy consumption. Taleghani et al. (2012a) use EnergyPlus

and Design Builder programs for modelling and simulating three types of transitional spaces in

three different cities. Moreover, Aldawoud and Clark (2007) use DOE2.1E software for

modelling and simulating courtyard and atrium in four different climates. Both computer

modelling are used to estimate the annual energy demand of modelled buildings. EnergyPlus

has more detailed simulation tools and options which enable the user to create building models

with detailed structure and properties in different conditions. Therefore, it is used in this

research for modelling the building types and achieving the reliable and valid results of annual

energy consumption.

Firstly, Open Studio Plug-in for Google Sketch-Up is used to create two models for courtyard

and atrium buildings. The figure 3 shows the perspective and plan of the models. It can be

seen that, the courtyard model consists of a rectangular building with internal dimensions of

18 x 18 meters and height of 3 meters. There is an empty space in the centre of the building

for courtyard with internal dimensions of 5.4 x 5.4 meters. A window is placed on each side of

the courtyard with width 4 and height 2 meters. There is no any window on other externalwalls in order to focus on the courtyard effects on energy demand. Moreover, the building is

one story and one zone. The atrium model is identically the same as courtyard model by

adding a skylight to the courtyard.

Then, in the EnergyPlus, the construction of the walls is defined by two layers of 10 cm brick

work which 15 cm air gap is between them for thermal insulation. The construction of the roof

is 10 cm concrete and the ceiling is made of acoustic tiles which 18 cm air gap is between the

roof and the ceiling. Furthermore, the ground floor is made of concrete and 5 cm insulation

board. The windows and skylight are made of double layers of 3 mm clear glass with 13 mmair gap between them.


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Figure 3: The models of courtyard and atrium buildings fir the simulation

Next, the mechanical heating and cooling is provided by using HVAC system which is based on

mechanical ventilation with heat recovery. Moreover, the natural ventilation is used depending

on the required fresh air in different months. The cooling set-point temperature is 25C and

heating set-point temperature is 20C. Based on the Updated Koppen-Geiger climate

classification (Kottek et al., 2006), five different climates are selected which are hot-arid, hot-

humid, temperate, continental and cold arid climates (figure 4). In simulations, weather data

are used from five different cities which are Riyadh (hot-arid), Bangkok (hot-humid), London

(temperate), Moscow (continental or cold) and Tehran (cold-arid).

Figure 4: World map of Koppen-Geiger climate classification

Finally, the results of annual heating and cooling energy demands of courtyard and atrium

buildings in different climates are compared. The less annual energy consumption means that

transitional model is more appropriate for buildings in that climate. Moreover, suitable actions

are suggested, based on relevant literatures, to enhance the performance of the selected

transitional space in the specific climate.


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4. Results of annual energy consumption

In this section, the main results from the EnergyPlus simulations will be presented and

interpreted. The results mainly are annual heating and cooling energy demand of both

courtyard and atrium building models in selected cities. There is a chart for results of each city

which presents the differences between annual energy demands in both building models.

These results can be useful in discussion section to achieve an answer for the research

question which is which model of the courtyard and atrium is more appropriate in different

climates. Table 1 in appendix is summary of the all results by numbers which will be used in

examine and explaining the charts for each city.

Firstly, the figure 5 shows the annual demands for both models in Riyadh which has a hot-dry

climate. It can be seen that atrium model consumes more energy for cooling than courtyard

model. The required energy for heating in both models is not considerable. In addition, in the

table, the total annual energy demand for both heating and cooling in atrium model is 109,870

KWh which is significantly more than courtyard model with 72,842 KWh energy demand. The

results may be explained by the fact that heat gain in atrium model is more than courtyard

during hot seasons which is not preferable. On the other hand, heat loss in courtyard model is

more than atrium model during the short period of winter. However, heat loss is not

considerable and its amount is a small number.

Figure 5: Annual heating and cooling energy demand for the model in Riyadh

Next, the results of annual energy demands for both models in Bangkok which has a hot-

humid climate are presented in the figure 6. Annual cooling energy demand in atrium model

which is about 97,533 KWh is considerably more than courtyard model which is 63,034 KWh.

The reason for this is that the heat gain in courtyard model is less than atrium model. There is

not energy consumption for heating. This may due to the fact that the outdoor air temperature

is high during the whole year and heat loss does not occur. Therefore, the heating load is not

required.


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Figure 6: Annual heating and cooling energy demand for the model in Bangkok

Next, the figure 7 demonstrates the annual energy demands for both models in London which

has a temperate climate. It is shown that courtyard model consumes more energy for heating

than atrium model. The required energy for cooling in both models is not sizeable. In addition,

the total annual energy demand for both heating and cooling in courtyard model is 75,464

KWh which is more than atrium model with 53,013 KWh energy demands. The differences

refer to the fact that in courtyard modelsheat loss is more than its heat gain with compared

to the atrium model especially during cold seasons which is not preferable. On the other hand,

during a short period of summers, overheating in atrium model causes the need for cooling

energy more than courtyard. However, this cooling energy is not considered.

Figure 7: Annual heating and cooling energy demand for the model in London

Then, the results of annual energy demands for both models in Moscow which has a

continental climate are shown in the figure 8. Annual heating energy demand in courtyard

model which is about 117,119 KWh is considerably more than atrium model heating energy

demand which is 80,551 KWh. It is due to that the heat loss in courtyard model is more thanheat gain with compared to the atrium model especially in cold seasons. On the other hand,


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the cooling energy demand in atrium model is more than courtyard model. However, the

consumed energy for cooling is not important because cooling is not required in case of using

natural ventilation due to the low outdoor temperature in Moscow.

Figure 8: Annual heating and cooling energy demand for the model in Moscow

Finally, the annual energy demands for both models in Tehran which has a cold-arid climate

can be seen in figure 9. In case of using atrium, the cooling energy demand increases and

heating energy demand decreases with compared to the case of using courtyard. The total

energy demand for both systems in atrium model is about 85,703 KWh which is more than the

total energy demand in courtyard with 62,556 KWh.

Figure 9: Annual heating and cooling energy demand for the model in Tehran

5. Discussion of the results and conclusion

In the previous section, the results are presented and explained. In this section, the cause of

the results will be examined and according to the results the most appropriate transitional

space will be indicated for each climate with mentioning of best actions to enhance their

performance.


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With regard to Riyadh, which represents hot-dry climate, one of the most risky problems of

indoor environments is overheating especially during the hot seasons. This is due to the high

outdoor temperature and high amount of solar incident during a long period of the year (figure

10). In case of using atrium, overheating occurs inside the atrium because of the high amount

of solar heat gain through the large area of the skylight glazing. This causes heat transfer from

atrium to the building through the walls and windows by conduction and convection.

Consequently, the heat gain of the building increases and extra energy is required for cooling

the indoor spaces. On the other hand, using courtyard as an outdoor space can increases

natural ventilation and cooling through the windows. Consequently, it can be said that using

atrium is not suitable for hot-dry climates and courtyard is the best alternative transitional

space for hot-dry climates. In addition, trees can be planted and fountains can be placed in

courtyards in order to increase the shadow and evaporative cooling through the windows of

the courtyard.

Figure 10: Monthly average outdoor temperature in selected cities (source: weather data of EnergyPlus)

In terms of Bangkok, which has a hot-humid climate, relative humidity is at high rates and

outdoor air temperature is at high degrees during the whole year (figure 10). Furthermore, the

solar incident is at high amount because of the high degrees of sun altitude angle in tropical

areas. In case of using atrium, overheating occurs during whole years because of the

continuous high temperature and solar radiation during the year. This overheating increases

heat gain of the building, and consequently, cooling energy increases. In addition, because of

the high rate of humidity, air circulation, natural cooling and ventilation is required

continuously. Courtyard makes the natural cooling and ventilation easy through its windows.

Therefore, courtyard is the appropriate transitional space for hot-humid climates.

Regarding to London, which represents temperate climate, the main challenge is increasing

heat gain during the long period of the year because the outdoor air temperature is mostly

under comfort temperature and solar radiation is not very effective especially in winters (figure

10). In case of using courtyard, external exposure increases, and consequently, heat loss


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increases through walls and windows which is not preferable. As a result, heating load

increases in the building. On the other hand, atrium makes a transitional space which its

indoor temperature is always higher than outdoor temperature. This is because of the high

amount of solar heat gain through its skylight. Therefore, heat losses decreases and the stored

heat in the atrium may transfer to the building by conduction and convection through the walls

and windows. Consequently, the heat gain increases and the heating load decreases.

Therefore, atrium is effective in decreasing annual heating energy. In addition, large openings

can be used in the atrium in order to provide natural cooling and ventilation in overheating

periods especially in summers.

In connection with Moscow, which has continental climate, the most risky issue is heat loss

because during the all years the outdoor temperature is low than comfort temperature (figure

10) and solar radiation is not considered because of the low altitude angle of the sun.

Therefore, Courtyard is not suitable for this climate because it increases exposure and as a

result heat loss increases. While, atrium can be a good solution to decrease heat losses and

increase solar heat gain. Furthermore, natural cooling can be used in case of overheating

during summers.

Tehran, which has a cold-arid climate, is characterised by very cold winter and hot summer

(figure 10). According to the results, courtyard is more suitable. However, it causes high heat

loss during cold seasons. On the other hand, atrium needs more cooling energy in summers. It

can be suggested to design an atrium which enables to be a semi open space with shading

devices during summers. This decreases heat loss in winters and heat gain in summers.

6. Research challenges and suggestions for future research

Transitional spaces are widely used in the designs in different climates. They may have

negative effects on the annual energy demand if they do not use appropriately. This research

has tried to assess the effects of courtyard and atrium on annual energy demand of buildings

by EnergyPlus simulations. The simulations have been carried out on typical building models

for courtyard and atrium buildings. The results offer very useful findings to compare both

transitional spaces and decide on the appropriate one for each climate with useful suggestions.

There are different forms, stories and structures of buildings. Therefore, the typical models,which have been used in simulations, may not represent the characteristics of all types of

buildings. For example, courtyard or atrium may have different effects on energy consumption

for a building with six stories with compared to the typical model which was one story.

Furthermore, the results may different for different forms and different structures of buildings.

As a next step in related analysis, future research might focus on the performance of different

forms of buildings or on transitional spaces in multi-story buildings in different climates. These

researches may give useful information for designers in sustainable design in different

climates.


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References list

Aldawoud, A., Clark, R. (2007) Comparative Analysis of Energy Performance between Courtyard and

Atrium in Buildings. Energy and Buildings40 (2008) 209-214

Ashley, J. (2011) Modification of Atrium Design to Improve Thermal and Daylighting Performance[online]MSc thesis. Queensland University of Technology. Available from

[30 April 2013]

Bagneid, A. (2006) The Creation of a Courtyard Microclimate Thermal Model for the Analysis of Courtyard

Houses [online] PhD dissertation. Texas A&M University. Available from

[25 May 2013]

Bahbudi, K. T., Taleghani, M., and Heidari, S. (2010) Energy Efficient Architectural Design Strategies in

HotDry Area of Iran [online]. Best 2 Conference. held 12-14 April 2010 at Hilton Portland &

Executive Tower. Portland. Available from [9 December 2012]

Baker, N. and Steemers, K. (2005) Energy and Environment in Architecture: A Technical Design Guide .

London: Taylor & Francis e-Library

Douvlou, E. D. (2004) Climatic Responsive Design and Occupant Comfort : The Case of the Atrium

Building in a Mediterranean Climate[online] Phd thesis. The University of Sheffield. Available from

[03 March 2013]

Ger, O., Tavil, A., and zkan, E. (2006) Thermal Performance Simulation of an Atrium Building. in

Proceedings of eSim 2006,Building Performance Simulation Conference. held 4-5 May 2006 at

Faculty of Architecture, Landscape, and Design, University of Toronto. Toronto. 33-40

Goulding, J. R., Lewis, O., and Steemers, T. C. (eds.) (1993) Energy in Architecture: the European

Passive Solar Handbook. London: B.T. Batsford Limited

Heidari, S. (2000) Thermal Comfort in Iranian Courtyard Housing [online] PhD thesis. University ofSheffield. available from < http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327670> [25 April

2013]

High Performance Commercial Building in India (HPCB) (n.d.) Solar Passive Design Features for Hot and

Dry Climates [online] available from [7 December 2012]

Hogue, R. (2011) Pragmatism and Mixed-methods Research. [26 May 2013] RJ Hogue Consulting

[online]. Available from [26 May 2013]
http://eprints.qut.edu.au/15780/http://repository.tamu.edu/handle/1969.1/ETD-TAMU-1662http://best2.thebestconference.org/pdfs/051_WB13-2.pdfhttp://best2.thebestconference.org/pdfs/051_WB13-2.pdfhttp://ethos.bl.uk/DownloadOrder.do?orderNumber=THESIS00613367http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327670http://high-performancebuildings.org/pdf/ECM1/ECM1_Technical_information_Hot-Dry.pdfhttp://high-performancebuildings.org/pdf/ECM1/ECM1_Technical_information_Hot-Dry.pdfhttp://rjh.goingeast.ca/2011/11/05/pragmatism-and-mixed-methods-research/http://rjh.goingeast.ca/2011/11/05/pragmatism-and-mixed-methods-research/http://rjh.goingeast.ca/2011/11/05/pragmatism-and-mixed-methods-research/http://rjh.goingeast.ca/2011/11/05/pragmatism-and-mixed-methods-research/http://high-performancebuildings.org/pdf/ECM1/ECM1_Technical_information_Hot-Dry.pdfhttp://high-performancebuildings.org/pdf/ECM1/ECM1_Technical_information_Hot-Dry.pdfhttp://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327670http://ethos.bl.uk/DownloadOrder.do?orderNumber=THESIS00613367http://ethos.bl.uk/DownloadOrder.do?orderNumber=THESIS00613367http://best2.thebestconference.org/pdfs/051_WB13-2.pdfhttp://best2.thebestconference.org/pdfs/051_WB13-2.pdfhttp://repository.tamu.edu/handle/1969.1/ETD-TAMU-1662http://eprints.qut.edu.au/15780/


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Hung, W. Y. (2003)Architectural Aspects of Atrium. International Journal on Engineering Performance-

Based Fire Codes 5 (4), 131-137

Kottek, M., Grieser, J., Beck, C. Rudolf, B., and Rubel, F. (2006) World Map of the Kppen-Geiger

climate classification updated. Meteorologische Zeitschrift[online] 15 (3), 259-263. Available from

[25 May 2013]

Medi, H. (2010) Field Study on Passive Performance of Atrium Offices [online]. 1st International

Graduate Research Symposium on the Built Environment. held 15-16 October 2010 at Middle East

Technical University (METU). Available from

[25

May 2013]

Rescher, N. (2012) Pragmatism: The Restoration of its Scientific Roots. New Jersey: TransactionPublishers

Samant, S. (2011) A Parametric Investigation of the Influence of Atrium Facades on the Daylight

Performance of Atrium Buildings [online] PhD Thesis. University of Nottingham. Available from

[5 May 2013]

Taleghani, M. Tenpierik, M., and Dobblesteen A. (2012a) The Effect of Different Transitional Spaces on

Thermal Comfort and Energy Consumption of Residential Buildings. in Proceedings of 7th Windsor

conference,The Changing Context of Comfort in an Unpredictable World. held 12-15 April 2012 at

Cumberland Lodge, Windsor. London

Taleghani, M., Tenpierik, M., and Dobbelsteen, A. (2012b) Environmental Impact of Courtyards: a

Review and Comparison of Residential Courtyard Buildings in Different Climates. Journal of Green

Building 7 (2), 113-136

Upadhyay, A. K. (2008) Sustainable Construction for the Future: Climate Responsive Design Strategies

for Sydney Metropolitan Region [online].Third International Conference of the Cooperative Research

Centre (CRC) for Construction Innovation. held 12-14 March 2008 at Gold Coast. Available from

[9 December 2012]
http://www.schweizerbart.de/papers/metz/detail/15/55034/World_Map_of_the_Koppen_Geiger_climate_classificathttp://www.schweizerbart.de/papers/metz/detail/15/55034/World_Map_of_the_Koppen_Geiger_climate_classificathttp://www.academia.edu/368277/Field_Study_on_Passive_Performance_of_Atrium_Offices_http://etheses.nottingham.ac.uk/2303/http://ebookbrowse.com/rp27-climate-design-for-sydney-pdf-name-rp27-climate-design-for-sydney-pdf-d321432334http://ebookbrowse.com/rp27-climate-design-for-sydney-pdf-name-rp27-climate-design-for-sydney-pdf-d321432334http://ebookbrowse.com/rp27-climate-design-for-sydney-pdf-name-rp27-climate-design-for-sydney-pdf-d321432334http://ebookbrowse.com/rp27-climate-design-for-sydney-pdf-name-rp27-climate-design-for-sydney-pdf-d321432334http://etheses.nottingham.ac.uk/2303/http://www.academia.edu/368277/Field_Study_on_Passive_Performance_of_Atrium_Offices_http://www.schweizerbart.de/papers/metz/detail/15/55034/World_Map_of_the_Koppen_Geiger_climate_classificathttp://www.schweizerbart.de/papers/metz/detail/15/55034/World_Map_of_the_Koppen_Geiger_climate_classificat


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Appendices

CityType of

model

Heating

Energy (KWh)

Cooling

Energy (KWh)

Total Energy

(KWh)

Riyadh Courtyard 3,414.39 69,427.83 72,842.22

Atrium 481.88 109,388.23 109,870.12

BangkokCourtyard 0.00 63,034.38 63,034.38

Atrium 0.00 97,533.00 97,533.00

LondonCourtyard 75,021.01 443.81 75,464.82

Atrium 45,583.67 7,429.70 53,013.37

MoscowCourtyard 117,199.37 1,136.66 118,336.03

Atrium 80,551.28 10,436.2490,987.51

TehranCourtyard 26,737.78 35,818.40 62,556.18

Atrium 12,289.12 73,413.99 85,703.11

Table 1: Total Annual energy demand for all models

Documents

Energy Performance of Courtyard and Atrium in Different Climates-libre