Enerji verimliliği kriterlerine göre otel tasarımı ve enerji modellemesi
Design and energy modeling of an hotel building according to energy efficiency criterias
Yazar: BERKEM ÖZ
Danışman: PROF. DR. AYŞEN DEMİRÖREN
İstanbul Teknik Üniversitesi / Fen Bilimleri Enstitüsü / Elektrik Mühendisliği Ana Bilim Dalı
Derece: Yüksek Lisans, 2015
Konu: Elektrik ve Elektronik Mühendisliği = Electrical and Electronics Engineering ; Enerji = Energy
Dizin: Fotovoltaik enerji = Photovoltaic energy ; Yenilenebilir enerji kaynakları = Renewable energy resources

Özet:
Son yıllarda, artan nüfus ve buna bağlı olarak endüstrileşme ile elektrik enerjisi talebinde büyük artışlar meydana gelmiştir. Dünya genelinde, enerji talebinin büyük bir kısmı fosil yakıtlarla karşılanmaktadır. Fakat, fosil yakıtların tükenme periyodunda olması ve çevreye vermiş olduğu olumsuz etkiler nedeniyle yenilenebilir enerji kaynaklarına yatırım yapılması ve enerji verimliliğinin arttırılması gerekmektedir. Dünyada ve özellikle Avrupa'da enerji verimliliği önemli bir şekilde teşvik edilmektedir. Bu konuda, şu anda belli seviyede çalışmalar yapılarak ileriki yıllar için de hedefler konulmuştur. Ülkemizde de enerji verimliliği uygulamaları son yıllarda önem kazanmıştır. Enerji verimliliği uygulamaları, çıkarılan yönetmeliklerle teşvik edilmeye başlanmıştır. Enerji talebini karşılamak için kurulacak yeni elektrik üretim tesislerinin tartışılmasının yanında, enerji verimliliğini tartışmak ve bu yolla, tüketimi azaltmak da önemli bir konudur.
Dünyada ve ülkemizde, elektrik ve fosil enerji tüketiminde konut binalarının ve diğer binaların oldukça önemli bir payı vardır. Tez kapsamında öncelikle, dünyadaki ve Türkiye'deki enerji kullanımının analizi yapılmıştır. Sonrasında, enerji verimliliği kavramı açıklanmış ve bu konudaki potansiyeller incelenmiştir. Binalardaki enerji verimlilğinin ölçülmesi amacıyla uluslararası geçerliliğe sahip LEED sertifikasyon sistemi incelenmiştir.
Tezin ikinci kısmında, LEED kriterlerine uygun olarak bir otel binasının enerji verimliliği incelenmiştir. Öncelikle, karşılaştırma yapmak için tasarımı yapılacak bina ile aynı mimari özelliklere sahip bir referans bina modellenmiştir. Bu modelleme için Design Builder programı yardımıyla 6 katlı ve otele uygun olarak tüm mahalleri tanımlanmış bir bina tasarlanmıştır. Design Builder programına ısıtma, soğutma aydınlatma, havalandırma ve bina dış kabuğu parametreleri tanımlanmış ve Energy Plus programı ile beraber simülasyon yapılmıştır. Energy Plus programı, saatlik ve günlük bazda simülasyon yapabilen oldukça geniş kapsamlı bir programdır. Design Builder ise, bu programa veri girilmesini ve çizim yapılmasını sağlayan bir ara yüz programıdır. İki program, bir çok iklimsel, mimari, mekanik ve elektriksel parametreyi göz önünde bulundurarak hassas sonuçlar vermektedir. Binanın konumuna ait enlem ve boylam değerleri girilmiş ve İstanbul'da tasarlanan otel için iklim verileri girilmiştir. Baz bina simülasyonundan sonra, tasarımı yapılacak olan bina modellenmiştir. Bu bina, kat yapısı ve toplam alan olarak baz binanın aynısı olarak tasarlanmıştır. Bu binada verimlilik elde edebilmek amacıyla bazı mimari, elektriksel ve mekanik parametrelerde değişiklik yapılarak yeni bir tasarım yapılmıştır. Buradaki önemli nokta, binanın tasarımı yapılırken maliyet konusu da göz önünde bulundurulmuş ve optimum bir tasarım yapılması hedeflenmiştir. Buna göre belli bir verimlilik değeri elde edilmiş ve referans bina ile karşılaştırılmıştır. Tasarımda, seçilenden daha büyük verimlilik değerlerine sahip
parametreler kullanarak verimliliği %50 seviyesinden daha yukarı çıkarmak mümkündür fakat, tasarımın gerçekçi olması amacıyla, belli seviyede verimliliğe sahip parametreler kullanılmıştır. Tasarımı yapılan binada, kendi elektriğini üretebilecek şekilde, çatıda fotovoltaik sistemin de kullanılması öngörülmüş ve buna göre simülasyon yapılmıştır. Otel binasının güneye bakan cephesindeki çatının büyük bir bölümünün fotovoltaik panellerle kaplanması durumunda elde edilecek elektrik enerjisi simülasyon sonucunda elde edilmiştir. Ayrıca elde edilen grafiklerle, üretilen enerjinin yıllık olarak dağılımı elde edilmiştir. Bunun yanı sıra programda elde edilen grafikleri inceleyerek, binanın yıl boyunca sergileyeceği enerji performansı incelenebilir.
Tezin son kısmında ise E-Quest programı ile aynı verilerle simülasyonlar tekrar edilmiştir. E-Quest, bina enerji modellemesinde Energy Plus ile beraber en yaygın olarak kullanılan programdır. Tezin bu bölümünde yine aynı şekilde baz bina ve tasarımı yapılacak olan bina modellenmiştir. Mekanik sistemler, aydınlatma sistemleri, bina kabuk detayları diğer programla yapılan simülasyonlarla aynı seçilmiştir. Sonrasında, bu iki modelin çıktıları detaylı olarak incelenmiştir. Enerji tüketimi olarak biribirine oldukça yakın değerler elde edilmiştir. Aradaki küçük farklılıkların da program algoritmasından kaynaklı olduğu düşünülebilir.
Çalışmanın amacı, binalardaki enerji verimliliği çalışmalarının faydalarını ve uygulamalarını incelemektir. Ayrıca, binalardaki enerji tasarruf potansiyelinin görülerek bu konuda yapılan çalışmaların önemini vurgulamaktır.

Abstract:
In the last years, because of increasing population and related to this the industrial improvement, there is a big demand risement about electricity. In the spread of the world, fossil fuels are used to meet the demand of the power. However, these recources are in the period of running out and they influence the environment in bad way. So, renewable energy sources and energy efficiency should be invested.
In the World and Europe, governments encourage the energy efficiency projects and they goal some achivements about this subject in the next years. As like in the Europe, energy efficiency applications become very important in our country. It is crucial to support energy efficiency projects instead of setting new energy production plants to meet the electricity demand. If 30 % efficiency rate could be obtained in the world, it is unnecessary to set up new 1000 power plants. This means big economic efficiency and protection of environment. In Europe, nearly 30 % efficiency rate is targeted in buildings. Tradable buildings and residences have an important role about energy consumption. Improvements on economy and population rate affects the consumption values. In our country, nearly half of energy consumption is consumed by buildings. It is easier to build new buildings with energy efficiency criterias. Making an existing building more efficient cost higher. As, all the systems are designed at the start of the project but for existing buildings, some mechanical and electrical systems should be changed so it is more difficult to replace the systems when people are living in that building.
In Turkey, nearly 70% of energy is imported from foreign countries. It is a high rate for a developing country. There are two ways to reduce dependence to another countries. First way is to reduce energy consumption. The second way is to increase renewable energy investments. Setting up new renewable energy power plants costs too high. It is too expensive to set up new power plants to meet the consumption of energy because industry consumes electricity too much. If the limited energy sources is thought in our country, the second section becomes more important. It is a good solution to reduce energy consumption in Turkey. It is too important to make the same task with a less energy. Energy efficiency is to make the same task with lower energy. It is different from energy saving precautions becuse, with energy saving precautions, less tasks can be done. For instance, turning off a lamp is an energy saving affair but, using efficient lamp is energy efficiency.
An important part of the consumed energy throughout the world is being used by the buildings of residence type and non-residential buildings. In thesis firstly, the situation of energy consumption is analysed in Turkey and spread of the World. Then, the concept and potential of energy efficiency is explained. Leed certification system which used for evaluating the projects about energy efficiency is examined in this study. Leed (Leadership in Energy and Environmental Design), is a green
building certification scheme developed by the United Stated Green Building Council. Since its inception, Leed has been the most known and widely used green building certification scheme in the World and has quickly became popular in Turkey too. Leed certified building designs go beyond the laws and regulations. Leed certified buildings become more energy efficient with efficient water use and they damage the environment less and these buildings as a result transformed into a more healthy liveable spaces.
In the second part of thesis, an energy modeling study is applied to a hotel building. To make a comparison, a reference building is designed like the hotel which will be modeled. Design Builder program is used for designing the six flat-hotel building. All the areas of the hotel are sketched. The parameters of heating system, cooling system, illumination, air conditioning and building envelope are defined to the program for both reference building and proposed building. Building interface insulation values, fenestration shadow coefficients, efficiency of equipments, illumination parameters, automation scenarios, building occupancy, renewable energy sources, roof material ratios are modelled. They are simulated with Energy Plus program. The program is a simulation program that can make hourly calculations and obtaining sensitive results by taking into consideration of many factors.EnergyPlus is a whole building energy simulation program that engineers, architects, and researchers use to model both energy consumption for heating, cooling, ventilation, lighting, and plug and process loads and water use in buildings.EnergyPlus includes integrated, simultaneous solution of thermal zone conditions and mechanical system response, subhourly, user definable time steps for interaction between thermal zones and the environment, with automatically varied time steps for interactions between thermal zones and mechanical systems, combined heat and mass transfer model, advanced fenestration models, illuminance and glare calculations and lighting control strategies.Design Builder is an interface program which supports Energy Plus. The programme combines rapid building modelling and ease of use with state of the art dynamic energy simulation.DesignBuilder provides advanced modelling tools in an use interface. This enables the whole design team to use the same software to develop comfortable and energy-efficient building designs from concept through to completion. These two programs give sensitive results regarding many weather, mechanical and electrical data. The latitude and longitude values of hotel are defined to the program. The weather data of Istanbul is applied. Meteorological values of weather data is used in the two programmes.
After simulating the reference building, the proposed building is designed and simulated. This building is designed like the referance buildng as architectural parameters. Computer simulation based energy modeling reveals the building's monthly energy expenses during design stage of the building. By this way, the new designed building energy-saving opportunities are selected by analyzing the most appropriate solutions. To obtain energy efficiency in proposed building, some architectural, mechanical and electricity parameters are changed. It is possible to see the results on the building through computer simulation by using the following parameters; climatic conditions at the location of your building, electro-mechanical systems of the building, function of the building, shell performance, the number of occupants of the building and so on. The cost analysis is too important point for the design ,so it should be optimised. An energy efficiency ratio is obtained and compared to the reference building. It is prerequisite to have at least 10% efficiency compared to reference building. It is possible to obtain extra points for the higher
values. It is possible to obtain an energy efficency ratio about 50% but the parameters are selected in a certain level to make a real simulation. Especially, when the renewable energy sources are used in design, higher efficiency rates can be obtained ,so the highest rated certificate level "Platin" can be achieved. There are also certificed, silver and gold stages.
In project, photovoltaic panels are used at the roof to produce electricity. The situation of using solar panels on the big part south roof is simulated and the results are examined. The yearly production values and yearly distribution of the produced energy are obtained as graphics. It is possible to check the energy performence of the building in a short way. Setting up photovoltaic panels cost too expensive in the first stage. However, when it is thought in long time, the electricity which is bought from grid is getting lesser. In addition, photovoltaic panels decrease greenhouse gas emissions. Because of these advantages, it is highly reccomended to build renewable energy sources.
In the last part of the thesis, a new energy modeling program is used for simulations. The program is called as E-Quest. It is spreadly used in the world for energy modeling studies and building energy use analysis tool that provides professional-level results with an affordable level of effort. It is too similiar to Energy Plus. It is possible to create a model of a building and calculate energy consumption values of this. The hotel building is re-simulated with this program by using the same values with the previous program. Firstly, a base building is sketched in the program. Then, mechanical and electrical systems are defined to E-Quest. Mechanical systems are same with Energy Plus. Lighting fixture powers and lighting power densities in zones are defined as the same. In both program there are very detailed information about the building. Building core details like orientation, thermal conductivity values, are taken into account. The second part of the study is to run the simulation. The consumption values are so close to each other.
It is too important to design the new buildings according to "Enegry Efficiency Law". The new buildings must have efficient architectural design, heating and cooling systems, insulation systems, electrical installation and lighting systems. Beside from the new buildings, it is possible to increase energy efficiency of existing buildings by changing lighting fixtures or mechanical systems. As, there is an inefficiency about energy in our country. By providing energy efficiency, setting new power plants can be cancelled. Also, decreasing greenhouse gas emissions protects environment. In this study, an hotel building is selected because, the hotels consume too much energy for providing luxury to people.
When the results are discussed, it is possible to see the advantages of green buildings. Nearly 28,6% efficiency in natural gas and electricity is obtained in Design Builder and Energy Plus programme. This efficiency rate is the difference of reference building and proposed building in those programmes. After these simulations, additional simulations of reference building and proposed building were done in E-Quest programme. In this programme, all the values are same with datasused in Energy Plus programme. In addition to these values, some extra necessary data were defined. When natural gas and electricity consumption values of reference and proposed buildings that designed in E-Quest programme are compared, 26,44% efficiency rate was obtained. There is a small difference between the efficiency rates of two programmes becuse, the algorithm of these is different from each other. Apart from these designs, a photovoltaic system is added to proposed building in Design Builder programme. This system provides extra efficiency. The electricity that bought from the grid decreases ,so it could be thought as efficiency. When the same proposed design with phovoltaic panels are compared to reference building, 38,53% efficiency is obtained. Designed photovoltaic panels are placed on the roof of the new hotel building.
The aim of the study is to examine the energy efficiency studies and define benefits and applications of these studies. Furthermore, it is too important to show the potential of energy efficiency for buildings. This study shows the energy consumption values of each systems in simulation programmes. It gives an idea to improve efficiency rates in systems. There is a chance to examine the results in two programmes.