A Parametric Model Proposal for Energy Efficient Settlement Texture and Building Design: Temperate-Humid Climate Zone
İdil Erdemir Kocagil, Gül Koçlar OralDepartment Of Architecture, Istanbul Technical University, Istanbul, TurkeyEnergy consumption in urban areas is constantly increasing to satisfy human needs that are shaped in line with developing technology and changing life conditions. Currently, urban areas account for three-quarters of global primary energy use and 70% of the world’s greenhouse gas emissions (UN-Habitat, 2020). It is extremely important to transform existing urban settlements considering energy-efficient solutions to keep the natural balance for ensuring a more sustainable world. Thus, the design of settlements is held responsible not only for the development of common urban spaces but also for the energy performance of buildings depending on the complex settlement geometry. Therefore, many different variables should be integrated into the settlement design process to provide optimum conditions for buildings by reducing heating, cooling, and lighting energy consumption. Regarding this goal, the proposed model aimed to reveal the interaction between settlement geometry and building form with a parametric approach by comparing the impact level of each design parameter related to settlement and building on building energy performance at different scales. A performance-oriented simulation method was used to assess settlement scenarios generated from simplified urban geometries to narrow down design options regarding the principles of early design stage exploration and iteration. The approach was implemented in Istanbul (temperate-humid climate), where ongoing urban renewal has already been changing existing settlement textures and increasing urban density, for making a significant contribution to the country’s economy by offering sustainable measures. In this framework, a four-staged model has been proposed to develop suitable design solutions via the determination of energy efficient values for the design parameters providing minimum energy consumption for a reference building in settlement texture. At the first stage, parameters related to climate, user, settlement texture, building, and active building sub-systems were defined based on the result of detailed research regarding related standards, regulations, and statistical data to establish reference building. At the second stage, as the outcome of the various combinations of identified values for design parameters related to settlement texture and building (plan type, number of floors, H/W ratio, settlement type), 18 settlement scenario alternatives composed of exactly identical buildings were generated. In the third stage, the effect of each design parameter on building energy performance was evaluated by calculating annual heating, cooling and lighting energy consumption per module for reference building defined in scenarios. Within this scope, respectively, the design parameters related to settlement and building (plan type, number of floors, H/W ratio, and settlement type), building envelope (opaque envelope layering and transparency ratio) and building control systems (solar control) were analysed from upper scale to lower scale by presenting the results comparatively to reveal energy efficiency level obtained from each design alternatives. In the fourth stage, due to the inability to determine the absolute solution in urban design (Oke, 1988), the data obtained as a result of the comprehensive evaluations were compiled for Istanbul in a sample application format on how decisions to be taken for the design parameters affect the energy performance of the building. The study revealed that heating energy consumption of buildings in the temperate-humid climate zone is higher than cooling energy consumption due to shorter cooling periods and then lighting energy consumption due to less need for artificial lighting in the residential buildings. In other words, various applications of design solutions aiming to reduce the heating energy consumption of buildings for the settlements to be developed in Istanbul are beneficial regarding the increase in energy efficiency level. In this respect, it was found that square plan due to more compact form than rectangular, pavilion due to higher amount of solar radiation gain through three façades than slabs, higher buildings due to better solar access than lower buildings and lower H/W ratios due to wider distance between buildings than higher H/W ratios ensured lower heating energy consumption for buildings. According to the results, in the settlements established based on proper decisions taken during the preliminary design process, a decrease of up to 26% was achieved in the total energy consumption of the building compared to other alternatives. In addition, it has been determined that the energy performance of buildings can be improved up to 19% with the integration of building envelope optimisation and solar control systems. Consequently, this approach has an opportunity to bridge an existing gap by synthesising best practices for decision-makers based on building energy performance objectives and energy-efficient design solutions by contributing to developing comprehensive awareness that will lead to a more sustainable built environment.
Keywords: Building energy performance, design parameters; energy efficiency; residential building design; settlement texture.Enerji Etkin Yerleşme Dokusu ve Bina Tasarımına Yönelik Parametrik Bir Model Önerisi: Ilımlı-Nemli İklim Bölgesi
İdil Erdemir Kocagil, Gül Koçlar Oralİstanbul Teknik Üniversitesi, Mimarlık Fakültesi, Mimarlık Anabilim Dalı, İstanbulKentsel yerleşmeler küresel enerji tüketiminin önemli bölümlerinden sorumlu oldukları için yeni geliştirilecek yerleşmelerin enerji etkin olarak tasarlanması güncel ve önemli bir yaklaşım olarak değerlendirilmektedir. Bu doğrultuda çalışmada enerji etkin yerleşme dokusu ve bina tasarımına yönelik geliştirilen parametrik bir model önerisinin sunulması amaçlanmıştır. Modelde tasarım parametrelerinin bina enerji tüketimi üzerindeki etki düzeylerini değerlendirmek için performans odaklı bir simülasyon yöntemi kullanılarak tasarım aşamasına yönelik uygun çözümlerin üretilmesi hedeflenmiştir. Önerilen model, ılımlı-nemli iklim bölgesinde yer alan ve hızlı bir kentsel dönüşüm sürecinden geçen İstanbul için uygulanmıştır. Belirlenen yerleşme dokusu ve binaya ilişkin tasarım parametrelerinin (plan tipi, kat sayısı, H/W oranı, yerleşme tipi) kombinasyonlarıyla 18 senaryo alternatifi üretilerek farklı ölçeklerde (yerleşme, bina, bina kabuğu, kontrol sistemleri) alınan tasarım kararlarının referans binanın enerji performansına etkileri analiz edilmiştir. Yerleşmelerin geometrisi, binaların birbirlerine göre konumlarına bağlı olarak güneş erişim düzeylerini kontrol etmekte ve enerji performansını etkilemektedir. İstanbul için konutlarda ısıtma enerjisi tüketimi soğutma ve aydınlatma enerjisine kıyasla yüksektir; dolayısıyla, ısıtma enerjisi tüketiminin azaltılabilmesi için yüksek güneş erişimi sağlayan düşük H/W oranlarına sahip ve ayrık nizamda konumlanmış binaların yer aldığı yerleşme dokuları öne çıkmaktadır. Enerji analizlerine göre, tasarım sürecinde alınan doğru tasarım kararlarıyla kurulan yerleşmelerde diğer alternatiflere kıyasla toplam enerji tüketiminde %26 oranına varan düşüş sağlanmış; bina kabuğu optimizasyonu ve güneş kontrol sistemlerinin entegrasyonuyla binaların enerji performansının %19 oranına kadar iyileştirilebileceği tespit edilmiştir. Yüksek enerji performansına sahip binalar ve sürdürülebilir yerleşmelere yönelik olarak tasarım kararlarının önemini vurgulayan bu çalışmada sunulan yaklaşım, karar verici paydaşlar için alternatif uygulamaları sentezleyerek kentsel planlama alanındaki mevcut boşluğun doldurulmasına katkı sağlamayı hedeflemektedir.
Anahtar Kelimeler: Bina enerji performansı, enerji etkinliği; konut binası tasarımı; tasarım parametreleri; yerleşme dokusu.Manuscript Language: Turkish
