zero energy building design in cairo, egypt (climate responsive architecture and planning)

8/13/2019 Zero Energy Building Design in Cairo, Egypt (Climate Responsive Architecture and Planning)

1/19

ENERGYEnergy Supply System

Electricity is used for heating and coo-ling in Egypt. It is also common to usenatural ventilation (cross ventilation)as well as passive thermal control.

Electricity Generation

In Egypt, electricity is mainly fromFossil Fuels (Oil and Natural Gas)andHydro power. Natural gas is used forcooking and DHW. There is growingdevelopment of Wind and CSP ener-gy, where by 2020 the installed capa-city of electricity is planned to be co-vered by 20% renewable energy.

Electricity Funding

The electricity prices are very low, dueto the subsidies (8.2 billion /Year).Prices for residential and ofces rangefrom1-6 c per kWh. Captive usage sys-tem has a limit of 50MW, as well as forprivate investments. Power purchaceagreements are for 25 years.

Water availability

Water is scarce and therefore not sui-table for evaporative cooling.

Cairo, Egypt, Africa 30N, 31E

CLIMATEClimate Zone: BWh

B- Dry Climates are characterized by

little rain and a huge daily tempera-

ture range.

W- stands for arid or desert, are used

with the B climates.

h- stands for Dry-hot with a mean an-

nual temperature over 18C in B cli-

mates only.

Recorded, design and average high

temperatures are 39, 34 and 27C si-

multaniously. Recorded, design and

average low temperatures are 5, 5

and 17C simultaniously. Mean annu-

al temperature is 22C.Mean relative humidity for an average

year is recorded as 35.2% and on a

monthly basis it ranges from 25% in

May to 46% in December.

CLIMATE RESPONSIVE ARCHITECTURE AND PLANNING Ismail Khater, Saif RashidPresentation1 Group Cairo

Desertec renewable energy grid

KuraymatZafarana

Aswan Giza

Industry

Agriculture

Gov. Sector & Public

Utilities

Residential

Commercial

Other

% Hydro

% Thermal

% Wind

Energy by use

Energy by type


2/19

CONCEPT

Estimated primary energy demand:

41,918 kWh/a

COMMENTS

Results for a Standard Ofce room:

The results are not satisfying. The coo-ling demand needs to be reduced in or-der to be able to have more oors andkeep the energy sources limited to onsiterenewables.

Results for a multi-storey building:

Results are not satisfying, as we need788m deep* borehoels, which means

800m2 plots which would be 12x67m. Anoption would be to reduce the depth ofthe boreholes.

The common International Style of theOfces is not suitable for this climate.

Outlook

Some of the rst proposals that could beintegrated to reduce energy demand:

- Using fans and natural ventilation canstore nighttime cooling in high mass inte-rior surfaces

- Adding solar shading devices and ins-talling smaller windows which still allowneeded indirect sunlight

- Use light colored building materials for

the exterior to minimize conducted heatgain as well as light interior paint to gainmore lighting

- Using enclosed well shaded courtyardsto provide Wind-protected microclimates,as well as narrow streets for buildingsself shading

- Raising the indoor comfort temperaturelimit will reduce air conditioning energyconsumption

CLIMATE RESPONSIVE ARCHITECTURE AND PLANNING Presentation1

Heating Cooling artificial light ventilation

Heating and Cooling System

Heating demand is 347 kWh/a whichaccounts for only 1% of the total ener-gy demand. On the other hand, thecooling demand exceeds 62% of totaldemand, with 15345 kWh/a.

Therefore, the main focus is to provi-de a cooling system which normallyuses natural ventilation, shading andother traditional, passive techniques.

Heat Pump / Boreholes

As a more efcient system it is re-commended to use heat pumps andgeothermal energy, this heat pumpwill have a COP (coefcient of perfor-mance) of 3 and will reduce the totalenergy demand to 13,973 kWh/a. Thelength of the borehole needed to co-ver the cooling and heating demandof one oor is 213 m. this heat pumpneeds electricity which should be pro-vided from renewable sources, whichin this case is from PV panels.

Photovoltaic

Annual Solar Radiation at a horizontalsurface is 2,000 kWh/m a. The maxi-mum annual Solar Radiation is 2,203kWh/m a at an angle of 30. The ef-ciency of PV panels used in calcu-lations is 12% calculating the mostefcient placement of photovoltaicsshowed that the tiltied roof with ang-le of 30 can generate 51,283 KWh,which can cover the demand of 3.7ofce oors.(see table)

Fig. 4: PROPSED EXTERIOR SOLUTIONS

Fig. 5: PROPSED INTERIOR SOLUTIONS

Fig. 3: CURRENT SOLUTIONS

Fig. 2: BOREHOLES CONFIGURATIONS

Fig. 6: PROPOSED URBAN SOLUTIONS

Fig. 1: ELECTRICITY DEMAND

Ismail Khater, Saif RashidGroup Cairo

* based on the height- distance ratio the area of the plot will be 396m2. the optimum depth of the boreholes will be 50m (see Fig. 2)

PROPOSAL


3/19

Altitude angle at noon (12:00h) in win-

ter is 33 above horizon and in sum-

mer 86 above horizon.

CLIMATE ANALYSIS

Air Temperature Range:

The average high temperature is 27C

and the average low is 17C.

The temperature difference between

day and night in summer is more than

10K (1st July 22C-33C/ 1st August

22C-37C). This situation will be use-

ful for night cooling.[1]Ground Temperature:

Ground temperature is the same as

the mean annual temperature which

is about 22C.[1]

Sky Cover Range:

The sky is clear as the mean annual

sky cover range is 33% and the aver-

age monthly range does not exceed

50% in any month.[1]

Humidity:

Evaporative cooling is theoretically

possible because the climate is clas-

sied as a dry one as the mean rela-

tive humidity for an average year is

recorded as 35.2%[1]. However, it is

not feasible to use evaporative cool-

ing due to water scarcity.[2]

Solar Radiation and Sun Path:

The mean annual average of solar ra-

diation on a horizontal surface is 876

Wh/sq.m per hour. the month with the

highest average solar radiation is July

with 1027 Wh/sq.m and the lowest is

December with 618 Wh/sq.m.[1]

Fig. 1: SUN PATH CHART (21 June to 21 December) [1]

Wind Velocity and Direction:

The direction of Prevailing wind is

North and North-West[3]. In addition,

theres a seasonal Hot-Dusty South-

West wind mainly in April, ventilation

openings in this orientation should be

avoided[4].

The average yearly wind speed is 4 m/

sec and almost the same for monthly

average, which is sufcient for naturalventilation.[1]

Fig. 2: WIND WHEEL [3]

DESIGN STRATEGIES

The climate data analysis shows that:

The optimum building orientation

that provides optimum sun control is

north-south.

North,north west orientation is the

orientation for optimum natural venti-

lation.

North-south oriented building with

catchers can combine both optimumsolutions, especially with the south-

ward tilted roof.

As a building structure and materi-

als, thick walls and sandstone can

support an optimum solution.

Less glazing in the facade is also im-

portant to prevent direct solar radia-

tion and heat transfer.Fig. 3: ORIENTATION/VENTILATION DESIGN CONCEPT [5]

Fig. 4: PSYCHROMETRIC CHART [1]

The design strategies for both resi-

dential and ofce buildings are simi-

lar, but there are some differences

due to different function such as; the

occupation hours, ventilation and

lighting (needed more in ofce build-

ing), internal heat loads, space plan-

ning (ofces are preferred more open

and exible with larger spans).

Cairo, Egypt, Africa 30N, 31E

CLIMATE RESPONSIVE ARCHITECTURE AND PLANNING Ismail Khater, Saif RashidPresentation2 Group Cairo


4/19

EXAMPLE 1:

VERNACULAR ARCHITECTURE

BAYT EL-SUHAYMI

EXAMPLE 2:

BEST PRACTICE

NEW AUC CAMPUS

CLIMATE RESPONSIVE ARCHITECTURE AND PLANNING Presentation 2

Short descriptionSuhaymi house is a traditional islam-ic/vernacular architecture house thatwas built in the year 1648, with a oorarea of 2000 m2.It lies in the heart ofCairo city, and is now owned by theEgyptian government and used as amuseum.[6]

Short descriptionThe American University Campus inCairo (AUC) is designed based ontraditional architecture criteria, host-ing educational, residential and ofcefunctions. It was built in the year 2008,covering 46,000 acres of land, andlies on the outskirts of Cairo. [12]

Climate Responsive ArchitectureThe House is a typical Courtyard Build-ing. [7] It has heavy bearing walls ofbrick & stone and roofs that are markedwith their thermal resistance proper-ties. Openings to the outside are verysmall and shaded, which protect thebuilding from the strong sun. The dec-orated wooden grillage (Mashrabiya)allow the needed amount of light topenetrate without overheating.[8]The means of cross-ventilation exist,while being able to trap the cool air-ow through the water fountain andcourtyard garden. Balconies are fac-ing the inside, which are mostly shad-ed during the day, allowing the cooledair in through pressure difference.Different Halls were used for winterand summer according to their orien-

tation.[8]

Climate Responsive ArchitectureThe AUC campus was built usingstone, marble and granite. Sandstonewalls reduce the cooling demandthrough their high thermal mass. Allofces have the possibility to be natu-rally ventilated, and also have natu-ral daylighting. The mechanical ven-tilation uses a chilled water system,which is 40% provided by co-genera-tion power method. 27 water fountainsincrease the relative humidity, coolingthe dry micro-climate of the campus.[12][13]Even though studies have been con-ducted to install renewable energy onthe buildings [15], all of the energy isfrom fossil fuels. The building orienta-tion and density is also doubted andcould have been improved.

DESIGN RULES

Natural Ventilation

Natural ventilation can store nighttimecoolth in high mass interior surfac-es, thus reducing air conditioning.[1]

Shading Devices

Window overhangs (designed for thislatitude) can reduce cooling demand.[1]

High thermal mass

High mass interior surfaces like stonefeel naturally cool on hot days andreduce day-to-night temperatureswings.[1]

Heating Demand

Equipment, lights & occupants will great-ly reduce winter heating demand.[1]

Fig. 10: SUHAYMI HOUSE (COURTYARD VIEW) [11]

Fig. 11: SUHAYMI HOUSE* (CROSS SECTION) [9]

Fig. 12: TYPICAL TRADITIONAL CITY SECTION [10]

Fig. 13: AUC CAMPUS (COURTYARD) [14]

Fig. 14: AUC CAMPUS (LIBRARY) [14]

Fig. 5: NATURAL VENTILATION EXAMPLES [1]

Fig. 6: SUN SHADING EXAMPLES [1]

Fig. 7: THERMAL MASS GRAPH [1]

Fig. 8: INTERNAL HEAT GAINS [1] Fig. 9: SUHAYMI HOUSE FLOOR PLAN [8]

Fig. 15: AUC CAMPUS (LAYOUT MAP) [12]


* Section is from M uhib Ad-Dmin Ash-Shfi house(1350). It is used herebecause of unavailability of data, but it represents the same concept.

NOTE: All Information (text, diagrams and images) marked with a [x] are refer-enced. The bibliography is located at the end of the attached PDF.


5/19

Cairo, Egypt, Africa 30 N, 31E

CLIMATE RESPONSIVE ARCHITECTURE AND PLANNING Ismail Khater, Saif RashidPresentation 3 Group Cairo

DESCRIPTION

Orientation (sun and wind)

From the weather data, best practiceand vernacular architecture exam-ple we conclude the best orientationfor the Building energy performanceis to be North-South with the longerfaade.[1][2] This is also suitable forthe prevailing wind direction (North-Northwest), making it possible to use

the required wind for ventilation.[1]Window size and placement

As the sky is categorized dominant byclear sky, the used percentage will bethe minimum of 35% of glazing [3], asthere is a need to maximize the heavyconstruction mass. Glazing will becomposed of 2.7 meter vertical pan-els to maximize supply and exhaustdifference on the northern and south-ern faades [4].

Shading system

Shading requirements will be met withxed horizontal louvers on the south-ern faade designed to fully shade theglazing by April 21st at noon. There is

no need for shading on the northernfaade. [5] As for east and west, fa-cade protrusions and recesses will bemade to reduce the direct solar radia-tion on a detached panel to eliminatethe thermal bridge.

Ventilation strategy

Natural ventilation will be mostlyused, through windows, two oppositewalls (cross ventilation), and also thepossibility to use a ventilation shaft

COMFORT LEVEL

From the European Standard EN15251 the outcome shows percent-ages of 74.6, 7.3 and 6.8 for catego-ries I, II and III simultaneously, total-ling a percentage of 88.7. The rest of11.3 percent lies in category IV, which

represents the hot days.[9] The over-all assessment shows that it is in-sufcient. When we alter the designtemperature by 2,3 and 4 K of upperlevel for adaptation to hot climates wereach categories III, II and I simulta-neously, all with 84 exceeding hours.

Mechanical ventilation (like ceilingfans) will have to be used to meetthe satisfying results. Using fans canmake temperatures seem cooler by 5degrees F with closed windows.[1]

through having openings in the cor-ridor slab and a ventilation shaft witha solar chimney effect caused by theheat of the PV panels to acceleratewind change in the summer months.[6] During regular to high wind veloc-ity the funnel setting of the PV pan-els will create the pressure differencesucking the air out (Bernoulli effect)[7]. Another ventilation method willbe the one-sided ventilation which is

forced by temperature difference.

Construction mass

Heavy construction mass is used inthe outer shell, as well as in interiorsurfaces, which reduce day and nighttemperature swings [1]. For the outerwalls sandstone is a good material tobe used because of its characteristics[8] and availability.

SOUTHSUMMER

WINTER

VENTILATION SECTIONWALL SECTION

ELEVATION (south)

PROTRUSIONS ELEVATION (north)

PREVAILING

WIND DIRECTION

ONE WALL

VENTILATION

CROSS

VENTILATION

WINDOW-to-SHAFT

VENTILATION

SHADING

NON-SHADING

BERNOULLI

EFFECT

NORTH


6/19

ENERGY CONCEPT

Demand for the optimized room

Annually:

thermal: cooling 5,870 kWh/a

heating 470 kWh/a

electrical:

heating &

cooling 2,113.4 kWh/a

art. lightning 1,099 kWh/a

Ventilation 1,596 kWh/a

sum: 4,808.4 kWh/a

Geothermal heat-

pump 1,682.9 kWh/a

Peak Chiller 860.9 kWh/a

sum: 5,238.8 kWh/a

solar radiation on:

Horizontal 40,320 kWh/a

Tilted 30 51,283 kWh/a

Daily:

max heating/cooling

demand 515 Wh/md

borehole length 144 m


Alternative system

Using bore holes with smaller distanc-

es in between that deliver 600 Wh/d

can solve the problem partly by cov-

ering the base load. In addition, elec-

tric chillers will be installed to cover

the peak demand, using the electricity

generated by the PV panels.

Assumption:

Building with 5.5 storeys (utilizing onlyhalf of the 6thoor area) and Distance

to Height ratio (1:1.5).

Building height = 21 m

Distances = 14 m (bldg. to bldg.)

Plot area = 336 m2

Basic cooling covered by

bore holes = 218.2 Wh/m2d

78% of cooling demand to be cov-

ered by Geothermal heat pump

(COP = 3.0)

22% covered by Electric chillers

(COP = 1.5)

Total electricity demand for one

storey ( Geothermal, Ventilation,

Lighting & Chiller) = 5,238.8 kWh/a Total demand for building =

5,238.8 X 5.5 = 28,813.4 kWh/a

[see attached document]Heating and Cooling System

According to data from Climate Con-

sultant, the building has six months

with average temperature above 23C

in which cooling is needed. Therefore,

the building will be a hybrid type with

cooling during summer months.[1]

Photovoltaic

The maximum Energy which can be

Generated from a tilted roof with an

angle of 30 is 51,283 kWh/a. This

amount of energy can cover the ener-

gy demand of more than ten storeys

using a geothermal heat pump with a

COP of 3 as shown in the table below.

Fig.4 Buildings Urban LayoutFig.2: Building distances


Fig.3 Building Concept

Heat Pump / Bore holes

The bore hole length from the simula-

tion done in TRNSYS Lite is 144 m per

oor, thus the property area required

for the 10 storey ofce will be 1,215.3

m2with a distance of 87 m between

the buildings which is not satisfying

for urban dense areas.[2]

Therefore, the limiting factor in this

case is the property area and the bore

holes.

Fig.1: Achievable no. of Storeys


7/19

URBAN CONTEXT

Explanation:

Due to the high solar radiation on Cai-

ro[1], combined with the clear skies[1],

it is possible to densify the built envi-

ronment (horizontally and vertically)

and still achieve the goal of a ZEB. In

this environment a ratio of 1.5 building

height to street width has been used

to reduce the heat island effect, infra-

structure requirements and shade thestreets to achieve a more comfortable

outdoor environment.[6]


The results, after creating and testing

the adapted building and the urban

setting are satisfying, with an excess

of 22, 469.6 kWh/a of electrical power.


Fig.5: Proposed urban context (plan)Fig.4: Proposed urban context (section)

COMMENTS

Results for an adapted ofce room:

The adapted building is performing

signicantly better than the Interna-

tional style building. This can be de-

scribed by the results of the simulation

done in TRNSYS lite in percentages

reduced as following [2]:

80.2% of articial lighting

42.3% of cooling energy 50% of mechanical ventilation

This has been made possible by ap-

plying the measures (materials, ori-

entation and comfort levels) derived

from the climate consultant outcome

[1], and from the vernacular architec-

ture examples (see presentation 2).

ZEB: Zero Energy Building

CONCLUSION

Relatively to the current use of fossil

fuels in Egypt, the results of the Ofce

Building are satisfying. As discussed

in the last section, other sources or

settings for the renewable energy use

or mix might be more suitable for an

urban environment, making some re-

strictions like building heights or street

width more exible.

In addition, companies could reduce

the energy demand by changing their

code of conduct and/or ethics, by im-

plementing measures such as chang-

ing the dress code, or changing the

working hours to better suit the em-

ployees according to the climate. By

that said, there is a need to change

the corporate culture.

Architecture could be looked at as

more of a challenge rather than a lim-

itation. At the end, a good design is

one that meets not only the style and

aesthetics but mainly the occupantscomfort criteria.

The results of the overall exercise

show that there is a great potential to

achieve ZEBs in Egypt, in a conve-

nient and manageable manner. For

21st century Architecture and Plan-

ning it is essential to pay a great deal

of attention to the climate in the initial

phases of any project.

SUBSTITUTION MEASURES

Even though there is no need to sub-stitute the implemented measuresand technology, as it covers the wholebuilding demand and even exceeds theelectricity needs, it is argued if the de-centralized PV technology is the best tobe used in Egypt.[3][5]

According to some studies, the useof PV modules requires more mainte-nance in hot dry climates (with the high-

er potential of sand storms) as the pan-els get dirty, and therefore reduce theefciency.[5] Therefore, a centralizedPV system (park) could be maintainedmore easily.

As for the efciency of PV itself, studieshave shown that using CSP technolo-gy results in a more efcient system inEgypt. This is mainly due to the fact thatthe Power generated by CSP could bestored, and therefore, used even dur-ing night time and during cloud coveredtimes.[4]

Still, for remote locations, the resultsof the study would be preferred, elimi-nating the need for constructing the in-frastructure and saving the resourcesneeded for them.



8/19

HafenCity University

Resource Efficiency in Architecture and Planning

Climate Responsive Architecture and Planning

Prof. Udo Dietrich

WS 11/12

Presentation 1

Location: Cairo, Egypt

Ismail Khater

Saif Rashid


9/19

CLIMATE

Climate Zone: BWh

B- Dry Climates are characterized by little rain and a huge daily temperature range. W-

stands for arid or desert, are used with the B climates. h- stands for Dry-hot with a mean

annual temperature over 18C in B climates only. [1]

Recorded, design and average high temperatures are 39, 34 and 27C simultaneously.

Recorded, design and average low temperatures are 5, 5 and 17C simultaneously. Mean

annual temperature is 22C. [2]

Mean relative humidity for an average year is recorded as 35.2% and on a monthly basis

it ranges from 25% in May to 46% in December. [2]

ENERGY

Energy Supply System

Electricity is used for heating and cooling in Egypt. It is also common to use natural

ventilation (cross ventilation) as well as passive thermal control.

Electricity Generation

In Egypt, electricity is mainly from Fossil Fuels (Oil and Natural Gas)and Hydro power.

Natural gas is used for cooking and DHW. There is growing development of Wind and CSP

energy, where by 2020 the installed capacity of electricity is planned to be covered by20% renewable energy. [3]

Electricity Funding

The electricity prices are very low, due to the subsidies (8.2 billion /Year). Prices for

residential and offices range from1-6 c per kWh. Captive usage system has a limit of

50MW, as well as for private investments. Power purchase agreements are for 25 years.

[4]

Water availability

Figure 2: electricity by sector [3] Figure 1: electricity by type [3]


10/19

Water is scarce and therefore not suitable for evaporative cooling.[5]

Electricity:

Heating demand = 347

Electricity For heat pump (COP 3) = 5,234

Cooling demand = 15,354

Ventilation = 3,192

Artificial lighting = 5,547

________

Total electricity demand (heat pump + lighting + ventilation) = 13973

roof surface

electricity

generation

from PV

number of

possible stories

elevated

modules 114.9192 30380 2.2

flat roof 168 40320 2.9

tilted roof (30%

angle) 194 51283 3.7elev. 20 124.6944 32770 2.34

Boreholes:

Stories area

need for

boreholes (m)

1 168 213

2 336 426

3 504 6393.7 621.6 788.1

Based on the rule height of building = distance between buildings The distance will be

19 m so the area available for boreholes will be 12 * 33 = 396

If: x: length of Borehole

n: no. of boreholes

= 788 = 788 (1)

10

= 396 (2)


11/19

Substitute eq.1 in eq.2.

788 10 = 396

= 50.2

n = 16 boreholei

COMMENTS

Results for a Standard Office room:

The results are not satisfying. The cooling demand needs to be reduced in order to be

able to have more floors and keep the energy sources limited to onsite renewables.ii


Results are not satisfying, as we need 788m deep* boreholes, which means 800m2 plots

which would be 12x67m. An option would be to reduce the depth of the boreholes.iii

The common International Style of the Offices is not suitable for this climate.

Outlook

Some of the first proposals that could be integrated to reduce energy demand:

- Using fans and natural ventilation can store nighttime cooling in high mass interior

surfaces [2]

- Adding solar shading devices and installing smaller windows which still allow needed

indirect sunlight [2]

- Use light colored building materials for the exterior to minimize conducted heat gain as

well as light interior paint to gain more lighting [2]

- Using enclosed well shaded courtyards to provide Wind-protected microclimates, as

well as narrow streets for buildings self shading [2]

- Raising the indoor comfort temperature limit will reduce air conditioning energy

consumption [2]

iThis is only a theoretical calculation and 100m boreholes will be used as the suggested in the task

iiBased on the assumptions from the calculations done before.

iiiBased on the common known best practice urban planning assumptions for street/building width.


12/19

[1] J. Grieser et al., World Map of Koeppen-Geiger Climate Classification.: www.gpcc.dwd.de,

2006.

[2] Robin Liggett et al., Climate Consultant.: www.energy-design-tools.aud.ucla.edu, 2008.

[3] Egyptian Electricity Holding Company,Annual Report. Cairo, Egypt: Ministry of Electricity and

Energy, 2009.

[4] New and Renewable Energy Authority (NREA),Annual Report 2010. Cairo, Egypt: Ministry of

Electricity and Energy, 2010.

[5] W. Hamza et al., Water availability and food security challenges in Egypt, Swiss Federal

Institute of Technology, Ed. Zurich, Switzerland: Center for Security Studies, 2010.


13/19




Prof. Udo Dietrich

WS 11/12

Presentation 2


Ismail Khater

Saif Rashid


14/19

CLIMATE ANALYSIS

Air Temperature Range:

The average high temperature is 27C and the average low is 17C.

The temperature difference between day and night in summer is more than 10K (1st July 22C-

33C/ 1st August 22C-37C). This situation will be useful for night cooling.[1]

Ground Temperature:

Ground temperature is the same as the mean annual temperature which is about 22C.[1]

Sky Cover Range:

The sky is clear as the mean annual sky cover range is 33% and the average monthly range does

not exceed 50% in any month.[1]

Humidity:

Evaporative cooling is theoretically possible because the climate is classified as a dry one as the

mean relative humidity for an average year is recorded as 35.2%[1]. However, it is not feasible to

use evaporative cooling due to water scarcity.[2]

Solar Radiation and Sun Path:

The mean annual average of solar radiation on a horizontal surface is 876 wh/sq.m per hour. the

month with the highest average solar radiation is July with 1027 Wh/sq.m and the lowest is

December with 618 Wh/sq.m.[1]

Altitude angle at noon (12:00h) in winter is 33 above horizon and in summer 86 above horizon.

Wind Velocity and Direction:The direction of Prevailing wind is North and North-West[3]. In addition, theres a seasonal Hot-

Dusty South-West wind mainly in April, ventilation openings in this orientation should be

avoided[4].

The average yearly wind speed is 4 m/sec and almost the same for monthly average, which is

sufficient for natural ventilation.[1]

DESIGN STRATEGIES

The climate data analysis shows that:

The optimum building orientation that provides optimum sun control is north-south. North,north west orientation is the orientation for optimum natural ventilation.

North-south oriented building with catchers can combine both optimum solutions, especially with

the southward tilted roof.

As a building structure and materials, thick walls and sandstone can support an optimum

solution.

Less glazing in the facade is also important to prevent direct solar radiation and heat transfer.

The design strategies for both residential and office buildings are similar, but there are some

differences due to different function such as; the occupation hours, ventilation and lighting (needed

more in office building), internal heat loads, space planning (offices are preferred more open and

flexible with larger spans).


15/19

DESIGN RULES

Natural Ventilation

Natural ventilation can store nighttime coolth in high mass interior surfaces, thus reducing air

conditioning.[1]

Shading Devices

Window overhangs (designed for this latitude) can reduce cooling demand.[1]

High thermal mass

High mass interior surfaces like stone feel naturally cool on hot days and reduce day-to-night

temperature swings.[1]

Heating Demand

Equipment, lights & occupants will greatly reduce winter heating demand.[1]

EXAMPLE 1:

VERNACULAR ARCHITECTURE

BAYT EL-SUHAYMI

Short description

Suhaymi house is a traditional islamic/vernacular architecture house that was built in the year

1648, with a floor area of 2000 m2. It lies in the heart of Cairo city, and is now owned by the

Egyptian government and used as a museum.[6]

Climate Responsive Architecture

The House is a typical Courtyard Building. [7] It has heavy bearing walls of brick & stone and roofsthat are marked with their thermal resistance properties. Openings to the outside are very small

and shaded, which protect the building from the strong sun. The decorated wooden grillage

(Mashrabiya) allow the needed amount of light to penetrate without overheating.[8]

The means of cross-ventilation exist, while being able to trap the cool airflow through the water

fountain and courtyard garden. Balconies are facing the inside, which are mostly shaded during

the day, allowing the cooled air in through pressure difference.

Different Halls were used for winter and summer according to their orientation.[8]

EXAMPLE 2:

BEST PRACTICE

NEW AUC CAMPUS

Short description

The American University Campus in Cairo (AUC) is designed based on traditional architecture

criteria, hosting educational, residential and office functions. It was built in the year 2008, covering

46,000 acres of land, and lies on the outskirts of Cairo. [12]

Climate Responsive Architecture

The AUC campus was built using stone, marble and granite. Sandstone walls reduce the cooling

demand through their high thermal mass. All offices have the possibility to be naturally ventilated,

and also have natural daylighting. The mechanical ventilation uses a chilled water system, which


16/19

is 40% provided by co-generation power method. 27 water fountains increase the relative

humidity, cooling the dry micro-climate of the campus.[12][13]

Even though studies have been conducted to install renewable energy on the buildings [15], all of

the energy is from fossil fuels. The building orientation and density is also doubted and could have

been improved.

Bibliography

[1] Robin Liggett et al., Climate Consultant 5.1,www.energy-design-tool.aud.ucla.edu, 2008

[2] W. Hamza et al., Water availability and food security challenges in Egypt, Swiss Federal Institute ofTechnology, Ed. Zurich, Switzerland: Center for Security Studies, 2010.

[3] Robin Liggett et al., Climate Consultant 5.1,www.energy-design-tool.aud.ucla.edu, 2008 (*.epw(climate) file from U.S. Department of energy,

http://apps1.eere.energy.gov/buildings/energyplus/cfm/weather_data.cfm)

[4] Dr. A.M. Hegazi et al., Egyptian National Action Program to combat Desertification, Ministry ofAgriculture and Land Reclamation, Desert Research Center, 2005

[5] Online:www.solardat.uorigon.edu/sunchartprogram.html, retreived 2011, University of Oregon, SolarRadiation Monitoring Laboratory

[6] Rabbat, Nasser.A Brief History of Green Spaces in Cairo, Umberto Allemandi & C. for Aga KhanTrust for Culture, 2004

[7] Brian Edwards et al. ,Courtyard housing: past present and future, Taylor & Francis, 2005

[8] Ibrahim, Abdelbaki Mohamed. Renovation of Bayt al-Suhaymi. In Alam al-Bina. Cairo: Center forPlanning and Architectural Studies, 38-42/200, 1998.

[9] http://www.greenstone.org/greenstone3/nzdl?a=d&c=ccgi&d=HASH011c18f48d81ff6aeed198f1.7.pp&sib=1&p.s=ClassifierBrowse&p.sa=&p.a=b

[10] Emad el-Den Ahmed Hassan Ali, Visual design guidelines for medium-sized cities,www.elib.uni-stuttgart.de/opus/volltexte/2003/1497/pdf/PART1.pdf, retreived 2011

[11] Image retreived from:www.hightoursegypt.com

[12] American University in Cairo,http://www.aucegypt.edu/newcairocampus/background/Pages/default.aspx,retrieved 2011

[13] Green Leads, edition: Fall 2010,http://www1.aucegypt.edu/publications/auctoday/AUCTodayFall10/Green_Leads.htm , retreived2011

[14] Images retreived from: AUC: Catalyst for Change, American University in Cairo,www.aucegypt.edu/offices/ouc/documents/catalystforchange.pdf, retreived 2011

[15] Menna Dessouki et al.,Installing Solar Panels at the AUC New Cairo Campus, 2010
http://www.energy-design-tool.aud.ucla.edu/http://www.energy-design-tool.aud.ucla.edu/http://www.energy-design-tool.aud.ucla.edu/http://www.energy-design-tool.aud.ucla.edu/http://www.energy-design-tool.aud.ucla.edu/http://www.energy-design-tool.aud.ucla.edu/http://apps1.eere.energy.gov/buildings/energyplus/cfm/weather_data.cfmhttp://apps1.eere.energy.gov/buildings/energyplus/cfm/weather_data.cfmhttp://www.solardat.uorigon.edu/sunchartprogram.htmlhttp://www.solardat.uorigon.edu/sunchartprogram.htmlhttp://www.solardat.uorigon.edu/sunchartprogram.htmlhttp://www.elib.uni-stuttgart.de/opus/volltexte/2003/1497/pdf/PART1.pdfhttp://www.elib.uni-stuttgart.de/opus/volltexte/2003/1497/pdf/PART1.pdfhttp://www.elib.uni-stuttgart.de/opus/volltexte/2003/1497/pdf/PART1.pdfhttp://www.elib.uni-stuttgart.de/opus/volltexte/2003/1497/pdf/PART1.pdfhttp://www.hightoursegypt.com/http://www.aucegypt.edu/newcairocampus/background/Pages/default.aspxhttp://www1.aucegypt.edu/publications/auctoday/AUCTodayFall10/Green_Leads.htmhttp://www.aucegypt.edu/offices/ouc/documents/catalystforchange.pdfhttp://www.aucegypt.edu/offices/ouc/documents/catalystforchange.pdfhttp://www.aucegypt.edu/offices/ouc/documents/catalystforchange.pdfhttp://www1.aucegypt.edu/publications/auctoday/AUCTodayFall10/Green_Leads.htmhttp://www.aucegypt.edu/newcairocampus/background/Pages/default.aspxhttp://www.hightoursegypt.com/http://www.elib.uni-stuttgart.de/opus/volltexte/2003/1497/pdf/PART1.pdfhttp://www.elib.uni-stuttgart.de/opus/volltexte/2003/1497/pdf/PART1.pdfhttp://www.solardat.uorigon.edu/sunchartprogram.htmlhttp://apps1.eere.energy.gov/buildings/energyplus/cfm/weather_data.cfmhttp://www.energy-design-tool.aud.ucla.edu/http://www.energy-design-tool.aud.ucla.edu/


17/19




Prof. Udo Dietrich

WS 11/12

Presentation 3(a)


Ismail Khater

Saif Rashid


18/19


19/19

COMFORT LEVEL

From the European Standard EN 15251 the outcome shows percentages of

74.6, 7.3 and 6.8 for categories I, II and III simultaneously, totaling apercentage of 88.7. The rest of 11.3 percent lies in category IV, which

represents the hot days.[9] The overall assessment shows that it is insufficient.

When we alter the design temperature by 2, 3 and 4 K of upper level for

adaptation to hot climates we reach categories III, II and I simultaneously, all

with 84 exceeding hours.

Mechanical ventilation (like ceiling fans) will have to be used to meet the

satisfying results. Using fans can make temperatures seem cooler by 5degrees F with closed windows.[1]

Bibliography

[1] Robin Liggett et al.,Climate Consultant 5.1,www.energy-design-tool.aud.ucla.edu, 2008

[2] http://www.greenstone.org/greenstone3/nzdl?a=d&c=ccgi&d=HASH011c18f48d81ff6aeed198f1.7.pp&sib=1&p.s=ClassifierBrowse&p.sa=&p.a=b, retrieved January 2012

[3] U. Dietrich, S. Calderon, Zero-Cooling-Energy-Buildings in hot Climates: Experiences and Results

from a University Teaching Course, HafenCity University Hamburg, Germany 2011[4] Prof. Dr. rer. nat. Udo Dietrich,Buildings Ventilation, HafenCity Universitt Hamburg, Department

Architektur, Bauphysik, Energietechnik in der Architekturausbildung

[5] Online:www.solardat.uorigon.edu/sunchartprogram.html, retreived 2011, University of Oregon, SolarRadiation Monitoring Laboratory

[6] Jrg Schlaich - Wolfgang Schiel, Solar Chimneys, Encyclopedia of Physical Science and TechnologyThird Edition, Stuttgart 2000

[7] Brian Edwards et al. ,Courtyard housing: past present and future, Taylor & Francis, 2005

[8] Phalguni Mukhopadhyaya et al., Hygrothermal Properties of Exterior Claddings, Sheathing Boards,Membranes, and Insulation Materials for Building Envelope Design, 2007

[9] From the excel sheet provided by Prof. Udo Dietrich for the class Climate Responsive Architectureand Planning, Hafencity University, Hamburg 2011
http://www.energy-design-tool.aud.ucla.edu/http://www.energy-design-tool.aud.ucla.edu/http://www.energy-design-tool.aud.ucla.edu/http://www.greenstone.org/greenstone3/nzdl?a=d&c=ccgi&d=HASH011c18f48d81ff6aeed198f1.7.pp&sib=1&p.s=ClassifierBrowse&p.sa=&p.a=bhttp://www.greenstone.org/greenstone3/nzdl?a=d&c=ccgi&d=HASH011c18f48d81ff6aeed198f1.7.pp&sib=1&p.s=ClassifierBrowse&p.sa=&p.a=bhttp://www.greenstone.org/greenstone3/nzdl?a=d&c=ccgi&d=HASH011c18f48d81ff6aeed198f1.7.pp&sib=1&p.s=ClassifierBrowse&p.sa=&p.a=bhttp://www.solardat.uorigon.edu/sunchartprogram.htmlhttp://www.solardat.uorigon.edu/sunchartprogram.htmlhttp://www.solardat.uorigon.edu/sunchartprogram.htmlhttp://www.solardat.uorigon.edu/sunchartprogram.htmlhttp://www.greenstone.org/greenstone3/nzdl?a=d&c=ccgi&d=HASH011c18f48d81ff6aeed198f1.7.pp&sib=1&p.s=ClassifierBrowse&p.sa=&p.a=bhttp://www.greenstone.org/greenstone3/nzdl?a=d&c=ccgi&d=HASH011c18f48d81ff6aeed198f1.7.pp&sib=1&p.s=ClassifierBrowse&p.sa=&p.a=bhttp://www.energy-design-tool.aud.ucla.edu/

zero energy building design in cairo, egypt (climate responsive architecture and planning)

Documents