FREE ELECTRONIC LIBRARY - Books, dissertations, abstract

Pages:     | 1 |   ...   | 32 | 33 || 35 | 36 |   ...   | 78 |

«CSAAR (7: 2010: Amman) Sustainable Architecture and Urban Development \ Edited by Steffen Lehmann, Husam Al Waer, Jamal AI-Qawasmi. Amman: The Center ...»

-- [ Page 34 ] --

Table 13 above ilIustrates total energy used by the flats before and after adopting the energy efficient features, assuming that the comfort level of the households remaining unchanged. Since the design features reduce the cooling load, 64% was deducted from the cooJing energy of each unit or flat. During the calculation of the reduced energy of the flats, the energy used by electrical appliances has been left unchanged as shown by the va lues in the second row of the table For example, the cooling energy of Unit A2 was 636 kWh before the reduction and it is 229 kWh after a reduction of 64%. The total energy used by Unit A2 was 1762 kWh before the reduction on the cooling energy. After the cooling energy of Unit A2 is reduced to 229 kWh, the consequent reduction in total energy use of Unit A2 is 1355 kWh as compared to the initial value of 1762 kWh. This is a reduction of 23% in the total energy use of Unit A2. The percentage reduction was calculated by subtracting the difference in energy use before and after reduction of 64% and then dividing this value by the total energy use before the reduction.

In a similar way, the percentage reduction on the total energy use of Units A2, A3, 82,84,85, CI and C5 is calculated as 23%, 32%, and 23%, 26%, 24%, 12% and 32% respectively. This is an average reduction of 26% on the total energy use ofthe building. This average reduction was found by adding the total energy use of aB thc units before (8439 k Wh) and after the reduction of 64% in cooJing energy (6262 kWh). The difference of these two values (2177 kWh) is divided by the total energy use before the reduction of64% (8439 kWh) and then multiplied by J00 to give the average percentage reduction of 26% on the total energy use ofthe units surveyed.

The percentage reduction in cooling energy is seen to be more in Units A3 and C5 because these units use 50% ofthe total energy in cooling (shown earlier in Section 5.3.2). Whereas, the percentage reduction in cooling energy of Unit CI i5 only 12% as it U5es only 19% of the total energy for cooling. It was shown in Section 5.3.2 that units A3 and C5 are more dependent on air conditioners as compared to other units in the building and Unit C J does not use air conditioners. The unit without air conditioners (Unit CI) is not as benefitted as those that have air conditioners because the reduction in energy use was directed at those who have air conditioners and are very much dependent on them.

Nevertheless, households of Unit Cl would have a better indoor climate with lower indoor temperatures and with lower energy use for cooJing by fans and lower costs.

Tahmina Ahsana & Orjan Svaneb 200 lt can thus be concluded that a 64% reduction in cooling energy literally implies that more than half of the devices that were used for cooling are no Ionger used. Households would use the fans for a lesser period of time or to enhance cross ventilation or when there is no air f1ow. It would also mean that those who are dependent on air conditioners might use it for a lesser period of time or probably do not need air conditioners.

Further reduction in total energy use is possible if the energy required for Iighting i8 reduced by using energy efficient lights. However, discussions on reducing energy use for lighting are outside the scope of this study as mentioned in Section 1.3.2.

6 Conclusion and Recommendation This study has identified the following energy efficient building features for the

context of Dhaka:

• Doubling the thickness of external walls with 280 mm brick walls including an air cavity of 50 mm on east and west.

• The use of hollow clay tiles (HCT) in place of weathering course for roofs.

• Horizontal overhang ratio of 1.3 for east orientations, 1.2 for west orientations, I for north orientations and 1 for south orientations respectively.

All the features that were analysed in this study for adoption in the case study building reduce the energy use for cooling. The study shows that it is possible to reduce the cooling load of the flats studied by 60-70% and hence reduce the total energy use of the f1ats surveyed by 26-30%.

Dhaka City Building Construction Act need to develop building codes to promote and inf1uence energy efficiency in buildings. The focus of the codes should be to incorporate energy efficient design features right from the design stage.

Considering the significant amount of energy used by the residential buildings in general and the prevailing energy crisis in Dhaka, it is important to adopt the reasonably simple energy efficient design features highlighted in this study. These features can reduce the total energy use of the f1ats in the case study building by a factor of one fourth and also provide increased comfort to the households. Energy efficient design features not only improve the energy efficiency of residential buildings, but can also provide reduced energy costs to users and playa role in improving the overall energy situation of the country Sustainable Architecture and Urban Development 201


Alvarado, lL., MartI'nez E. (2008). Passive Cooling ofCement-Based Roofs inTropical Climates. Energy and Building, 40 (3), 358-364.

BBS. (2008). Statistical Pocket Book ofBangladesh 2007.Bangladesh Bureau of Statistics Planning Division: Ministry ofPlanning.

Chowdhury, A.A., Rasul, M.G. & Khan, M.M.K. (2006). Towards Energy Efficient Building Assets. A Review on Sub-Tropical Climate.

Fifteenth Symposium on lmproving Building Systems in Hot and Humid Climate.

[Online].Available:http://repository.tamu.edulbitstrearnJhandleI1969.114 54lIESL-HH-06-07-30.pdf?sequence=1. [accessed 22 December, 2008].

Clarke,lA. & Maver, T.W. (1991). Advanced Design Tools for Energy Conscious Building Design: Development and Dissemination. Building and Environment, 26( I), 25-34.

Development and Land Use Policy Manual, Energy Efficient Building Design.

(2004) [Online],Availabe: http://www.fremantIe.wa.gov.aulcouncil/resource/ DBH 12_EnergLEfficient.pdf.[ accessed 28 December, 2008].

Dhaka Mirror. (2009). Sufferings of City Dwellers Mount Due to Severe Power Crisis. [OnIine]. Available: http://www.dhakamirror.comJ?p=3428.

[accessedlO March, 2009].

Encyclopaedia ofthe Nations. (2010). Bangladesh. [Online]. Available:

http://www.nationsencyclopedia.comleconomies/Asia-and-the­ Pacific/Bangladesh.html Gut, P. & Ackerknecht, D. (1993). Climate Responsive Building: Appropriate Building Construction in Tropicai and Subtropical Regions.

Switzerland: SKAT.

Hancock, J.M. (2006). Dhaka Electric Supply Company Hosts Final USEAfUSAID Utility Partnership Exchange Program With U.S.

Distribution Utilities. [OnIine], Available:http://www.usea.orgiPrograms/EPP/EPP._News/DESC0_12_

2006.pdf Henning, H.M. (2007). Solar Assisted Air Conditioning ofBuildings - An Overview. Applied Thermal Engineering, 27 (10), 1734-1749.

Mozumder,P. & Marathe, A. 2007.Viewpoint: Causality Relationship Between Electricity Use and GDP in Bangladesh. Energy Policy, 35 (1),395­ 402.

Nagarajan, N. (2006). Energy Efficiency Improvement in Buildings. Proceedings ofthe India-IEA Joint Workshop on Energy Efficiency in Buildings and Building Codes. New Delhi, India.

202 Svaneb Tahmina Ahsana & Ossen, D.R., Ahmad, M.H. & Madros, N.H. (2005). Optimum Overhang Geometry for Building Energy Saving in Tropical Climates. Journal of Asian Architecture and Building Engineering, 4(2), 563-570.

People's Report 2004-2005. (2006). BangJadesh Environment. Dhaka: Unnayan Shamannay Raeissi,S. & Taheri, M. (1999). Energy Saving by Proper Tree Plantation.

Building and Environment, 34( 1999),565-570.

Reza, S.l. (2008). Housing Crisis. The Financial Express, Dhaka. [Online].

Available:http://www.thetinancialexpressbd.info/search index. php?pag e=detail_news&newsjd=41131. [accessed 20 December, 2008].

Tang, R. & Etzion, Y. (2004). On Thermal Performance ofan Improved Roof Pond for Cooling Buildings. Building and Environment, 39 (2), 201­ 209.

Tham, K. W. (1993.) Conserving Energy without Sacrificing Thermal Comfort.

Building and Environment, 28 (3), 287-299.

Tuhin, F. (2008). Revisiting the Energy Scenarioiln Bangladesh.[Online].

Avai lable:http://energybangla.com/index. php?mod=artic le&cat=Somet hingtoSay&article= 1055. [accessed 17 December, 2008J.

United Nations. (1991). Energy Efficient Design: A Guide to Energy Efficiency and Solar Applications in Building Design. ECE Energy Series No. 9.

New York: Uni ted Nations.

United Nations. (1999). World Urbanization Prospects: The 1999 Revision. New York: United Nations.

UNEP. (2007). Buildings and Climate Change: Status, Challenges and Opportunities. United Nations Environment Programme.

Vijaykumar, K.C.K.. Srinivasan, P.S.S. & Dhandapani, S. (2007). A Performance ofHollow Clay Tile (HCT) Laid Reinforced Cement Concrete (RCC) Roof for Tropical Summer Climates. Energy and Buildings, 39 (8), 886-892.

Wong, N.H. & Li, S. (2007). A Study ofthe Effectiveness ofPassive Climate Control in Naturally Ventilated Residential Buildings in Singapore.

Building and Environment, 42 (3), 1395-1405.

Yang, K. H. & Hwang, R. L.(J993). The Analysis ofDesign Strategies on Building Energy Conservation in Taiwan. Building and Environment, 28(4),429-438.

Sustainable Architecture and Urban Development 203 Experimental Studies of a Passive Cooling Roof in Hot Arid Areas Hamida Ben Cheikh l 1 Departement d'architecture, Universite ' de Laghouat, Laghouat, Algeria Abstract An experimental study of passive cooling roof was carried out for a typical summer day of June for Laghouat in Algeria. The proposed roof design is composed of a metal plate ceiling over which lies a bed of rocks in a water pool.

Over this bed is an air gap separated from the extemal environment by an aluminium plate. The upper surface of this plate is painted with a white titanium­ based pigment to increase the radiation ret1ection process during daytime.

Several passive modifications have been introduced to the roof in order to reduce indoor air temperature in hot climates. An experimental investigation, employing passive procedure, has been carried out to study the possibility of reducing air temperature in buildings. The results show that the air temperature can decrease with a range from 6 to lOOK. This decrease can further be lowered by 2 to 3°C if night natural ventilation ofbuildings is allowed.

Keywords: Evaporative cooling; Evapo-rejlective, Roof Hot dry climate; Night ventilation.

204 Hamida Ben Cheikh 1 Introduction In regions with arid climates such as Laghouat in southern Aigeria, excessive heat is the major problem that causes human thermal discomfort, as concluded Bencheikh & Bouchair (2004). Cooling is then is the basic requirement of building occupants. In modem buildings, this can be provided by mechanical and electrical instruments.

Traditional architecture in hot climate had many passive aspects which contributed to thermal comfort in dwellings, such as, compact urban heavy building structure, white painted external surfaces, blind facades, open courtyards, etc. The presence of trees, vegetation and water around the building in modifying the thermal microc1imate was weB appreciated. With the advent of energy crisis there has been a renewed interest in those aspects of architecture which contributed to thermal comfort in a building without or with minimum energy consumption, Bouchair (1989,2003,2004). Unlike rural areas, where the building is most exposed to external environment via its facades and roof, in urban area the most exposed part of the building to radiation and winds is the roof as shown in Fig. 1 In many studies such as Runsheng, Etzion, and ErelJ (2003), Jain (2006) and Amer (2006) show that the heat gain through the roofpresent 50% ofthe total heat gain in buildings.

Pages:     | 1 |   ...   | 32 | 33 || 35 | 36 |   ...   | 78 |

Similar works:

«Die UmfrageDie Antworten Herr Ingolf Christiansen, Beauftragter für Weltanschauungsfragen, Ev.-luth. Kirchenkreis Göttingen / Hannover, Mitglied der EnqueteKommission des Deutschen Bundestages „Sogenannte Sekten & Psychogruppen“, Autor einschlägiger kritischer Literatur zum Thema Satanismus: 1. Frage: Satanisch relevante Literatur ist überall im Internet und auch im Buchhandel frei zugänglich und frei zu erwerben. Mir ist kein Fall bekannt, in der einschlägige Literatur der...»

«Staatlich anerkannte Fachhochschule für Sozialwesen Catholic University of Applied Sciences Kooperationsprojekt der KHSB und DGfT Dramaund Theatertherapie Zertifizierte Weiterbildung September 2014 – November 2017 4. Durchgang Inhaltsverzeichnis 1. Kurzbeschreibung 1 2. Zielgruppe 2 3. Arbeitsfelder 2 4. Teilnahmevoraussetzungen 3 5. Zulassungsseminar 3 6. Ziele 4 7. Struktur der Weiterbildung 5 8. Module 6 9. Termine 12 10. Abschluss 13 11. Kosten 13 12. Veranstaltungsort 13 13. Dozenten...»

«Qualifizierte Personen für die Energetische Inspektion nach EnEV § 12 Henke Udo, Dipl.-Ing. Tel.: 0351-8531667 / E-Mail: u.henke@innius-doe.de INNIUS DÖ GmbH Magdeburger Str. 11 01067 Dresden (Sachsen) Website: www.innius.de Höppchen Falko, Dipl.-Ing. (BA), TGS Planer Tel.: / E-Mail: f.hoeppchen@innius-doe.de INNIUS DÖ GmbH Magdeburger Straße 11 01067 Dresden (Sachsen) Website: Szelig Janine, Dipl.-Wirt.-Ing. Maschinenbau/Energietechnik Tel.: 0351-8531667 / E-Mail: j.szelig@innius-doe.de...»

«HANS-JOACHIM GÄRTNER VOLKER SCHARF Chemische Egg Races in Theorie und Praxis 17 Vorschläge zur Gruppenarbeit von Mädchen und Jungen im Chemieunterricht der Sekundarstufe I Realschulkonrektor Hans-Joachim Gärtner Realschule Baumholder Im Brühl 20, 55774 Baumholder Professor Dr. Volker Scharf Abteilung für Didaktik der Chemie Adolf-Reichwein-Straße 2, 57068 Siegen Online-Ausgabe 2001 © by Hans-Joachim Gärtner und Volker Scharf Bei dieser Ausgabe handelt es sich um eine überarbeitete...»

«Elementanalyse im Rasterelektronenmikroskop mit Hilfe von Auger Electron Appearance Potential Spectroscopy und Disappearance Potential Spectroscopy Diplomarbeit von Erik Essers Elementanalyse im Rasterelektronenmikroskop mit Hilfe von Auger Electron Appearance Potential Spectroscopy und Disappearance Potential Spectroscopy Diplomarbeit von Erik Essers Referent: Prof. Dr. H. Kohl Korreferentin: Prof. Dr. D. Gerthsen externe Diplomarbeit der Universität Karlsruhe (TH) durchgeführt in der...»

«Studierende und Selbständigkeit Ergebnisse der EXIST-Studierendenbefragung n ie d tu S BMBF STUDIE Impressum Die Untersuchung wurde im Rahmen der wisBMBF STUDIE senschaftlichen Begleitforschung zu dem Herausgeber BMBF-Programm „EXIST – Existenzgründer Bundesministerium für aus Hochschulen“ vom Fraunhofer-Institut für Bildung und Forschung (BMBF) Systemtechnik und Innovationsforschung in Referat Öffentlichkeitsarbeit Karlsruhe durchgeführt. 53170 Bonn Bearbeiter: Jens Görisch...»

«Namibia Sossusvlei Tour März 2007 1. Tag (06.03.07) Anreisetag: Mit Rail&Fly nach Frankfurt. Abflug abends um 22:30 Uhr nach Namibia. Bis auf Nehle und Gesche, die schon früher angereist sind, sitzen wir alle im gleichen Flieger, kennen uns aber noch nicht. Nur Lilo hätte uns im Flieger eigentlich schon auffallen können, da sie den Nachtflug mehr mit Spaziergängen zwischen den Reihen als mit Schlafen verbracht hat.2. Tag (07.03.07) Ankunft um 09:30 Uhr in Windhoek. Erstes Treffen mit...»

«Abgrenzungsbeirat beim Bundesministerium für Gesundheit, Familie und Jugend Gutachten des Abgrenzungsbeirates gem. § 49a AMG zu well & active Eukalyptus-Balsam für Babys und Kleinkinder im Rahmen der Beratung der Bundesministerin für Gesundheit, Familie und Jugend und des Bundesamtes für Sicherheit im Gesundheitswesen gem. § 49a Arzneimittelgesetz (AMG), BGBl. Nr. I 185/1983 i.d.g.F. 1.) Kurzdarstellung: Das Produkt wurde in Hofer-Werbeaussendungen (Oktober und Dezember 2007) als...»

«Inhaltsverzeichnis Abkürzungsverzeichnis i Abbildungsverzeichnis iii Gegenstand und Ziel der Ausarbeitung 1 Teil A: Einsatz innovativer Kommunikationsinstrumente auf dem Werbemarkt 2 1. Die Teilnehmer im Werbemarkt und deren Entwicklung 2 1.1 Werbungtreibende Unternehmen 2 1.2 Medienanbieter 4 1.3 Rezipienten 6 2. Einsatz innovativer Kommunikationsinstrumente auf dem Werbemarkt 10 2.1 Sonderwerbeformen im Fernsehen 10 2.2 Multimedia-Kommunikation 11 2.3 Viral-Marketing 12 2.4 Video-Ads 13 Teil...»

«Anmeldung Abmeldung Bürozeiten Auskunft Achtung: Erster Anmeldetag ist Dienstag, der 20. Oktober 2015! Das Jahresprogramm ist für Kinder und Jugendliche im Alter von sechs bis 16 Jahren konzipiert. Einige Angebote richten sich auch an Kinder unter sechs Jahre sowie an Erwachsene. Eine schriftliche Anmeldung mit Unterschrift der/des Erziehungsberechtigten muss für jede Veranstaltung, die mit einer Veranstaltungsnummer versehen ist, erfolgen. Achtung: Die Teilnehmerzahl ist bei diesen...»

<<  HOME   |    CONTACTS
2016 www.book.dislib.info - Free e-library - Books, dissertations, abstract

Materials of this site are available for review, all rights belong to their respective owners.
If you do not agree with the fact that your material is placed on this site, please, email us, we will within 1-2 business days delete him.