Enerji verimliliği kapsamında binalarda fotovoltaik güç sistemlerinin uygulamalı analizi
Applied analysis of photovoltaic power systems in buildings within the scope of energy efficiency
Yazar: SERCAN KESKİNEL
Danışman: PROF. DR. SERMİN ONAYGİL
İstanbul Teknik Üniversitesi / Enerji Enstitüsü / Enerji Bilim ve Teknoloji Ana Bilim Dalı
Derece: Yüksek Lisans, 2015
Konu: Enerji = Energy

Özet:
Enerji verimliliği ve daha spesifik olarak binalarda enerji verimliliği konusunda fotovoltaik güç sistemlerinin binaların enerji verimliliğini ne ölçüde artırabileceği ve şebeke elektrik enerjisine olan bağımlılıklarını ne ölçüde azaltılabileceğinin araştırıldığı bu tez kapsamında, 2011 yılında yayınlanan ve 2013 yılında güncellenen Elektrik Piyasasında Lisanssız Elektrik Üretimine İlişkin Yönetmelik kapsamında Mayıs 2013'te kurulumu tamamlanan ve Temmuz 2013'te onayı yapılan Prokon-Ekon Şirketler Grubu'nun Ankara/Kazan'daki binasına çatı üzeri olarak uygulanan fotovoltaik güç sistemi teknik ve mali yönden incelenmiştir. Sistemin yatırım maliyeti, üretimi, toplam getirisi ve performansı dikkate alınarak Türkiye şartlarında bu gibi projelerin yapılabilirlik olasılıkları analiz edilmiştir. 2012 yılında Resmi Gazete'de yayınlanan Enerji Verimliliği Strateji Belgesi ile Türkiye'nin enerji verimliliği konusunda belirlediği hedeflere ulaşım hususunda fotovoltaik güç sistemlerinin nasıl yarar sağlayabileceği de araştırılmıştır.
Sistemin onay tarihi olan Temmuz 2013 sonrası onsekiz aylık dönem boyunca, binanın elektrik enerjisi tüketimi ve fotovoltaik güç sistemi tarafından üretilen elektrik enerjisi değerleri dikkate alınarak sistem mali yönden incelenmiştir. Yapılan mali analizler ve incelemeler sonrasında sistemin ekonomik olarak uygulanabilir olduğu sonucuna varılmıştır. Yapılan hesaplar sonrasında, sistemin on seneden daha az bir süre içerisinde kendisini geri ödeyebileceği öngörülmüştür.
Fotovoltaik hücre teknolojileri ile fotovoltaik hücrelerin geçmişten günümüze gelişimi, bir fotovoltaik güç sisteminin örnek bir güneş paneli ve evirici ile nasıl tasarlanacağı, bir fotovoltaik güç sisteminin performans oran hesabı gibi konular tez kapsamında incelenen konulardan bazılarıdır. Özellikle fotovoltaik güç sistemleri için çok önemli ve sıklıkla kullanılan bir parametre olan Sistem Performans Oranı'nın nasıl hesaplanacağı ve profesyonel yazılımlar vasıtasıyla ne ölçüde doğru olarak öngörüldüğü açıklanmıştır. Tez kapsamında incelenen mevcut fotovoltaik güç sisteminin 2014 yılı için Sistem Perfomans Oranı hesap edilmiş ve gerçek ölçüm değerleri ile tasarım öncesi öngörülen oranların elde edilip edilemediği irdelenmiştir.
Enerjide dışa bağımlılığı günden güne artan Türkiye için, yükselen enerji talebi gerçeği ile birlikte fotovoltaik güç sistemleri gibi enerji kaynağı temiz ve sonsuz olan bir teknolojiden nasıl kazanımlar elde edebileceği, bu kazanımları nasıl ve ne ölçüde maksimize edebileceği de bu tez kapsamında araştırılmıştır. Fotovoltaik güç sistemlerinde yabancı ülkelerde verilen destek türleri ile Türkiye'deki destekler karşılaştırılarak teşvikler ve destekler konusunda da önerilerde bulunulmuştur.

Abstract:
In this thesis, photovoltaic power systems in buildings is evaluated within the scope of energy efficiency with an existing rooftop photovoltaic system is located in Ankara province of Turkey. The photovoltaic power system was installed in May 2013 and approved in July 2013 by TEDAŞ (Turkish Electricity Distrubiton Company). Since that time the system has been producing electricity and the produced electricity has been using to decrease electricity demand and to increase electricity independence of the building. The building has been using the electricity produced by photovoltaic power system and the electricity of the grid simultaneously. While the produced electricity is higher than electricity demand of the building, remaining electricity can be sold within the legislation which named The Legislation Regarding to Unlicensed Electricity Production on Electricity Market published in 2011 and updated in 2013 by EPDK (Republic of Turkey Energy Market Regulatory Authority).
26% of primary energy demand and 43% of total electricity consumption was consumed by building sector in 2012 in Turkey. Because of the energy demand and the total electricity consumption in Turkey is increasing year after year, building sector is getting more attention as one of the main responsible with its large proportions there. Thence some targets have set in Energy Efficiency Strategy Document which is published in 2012 to increase energy efficiency and decrease energy intensity which was recorded as 0,19 TOE/1000 2005 US$ in 2012, higher than most of developed countries and decrease external dependency on energy as well. In the document specific targets regarding the building sector have set. One of the most remarkable targets was "at least ¼ of the existing building stock in 2010 will provide at least 20% of the annual energy needs from renewable energy sources and will become sustainable and eco-friendly buildings until 2023." Photovoltaic power systems will be one of the most important factors there to achieve the targets.
The basic fundamentals of photovoltaics, the history and the classifications of photovoltaic cells, state-of-the-art photovoltaic modules, the main components of photovoltaic power systems, the designing criterias of photovoltaic power systems have been examined in this study. First generation, second generationd and third generation of photovoltaic cells were explained with subtopics and necessary informations. Furthermore an example of how to design photovoltaic power systems was carried out with the help of technical and electrical values of a random photovoltaic module and a solar inverter. While designing the compatibility of the photovoltaic module and solar inverter, the climate features have also been taking into account as it should be.
The current status of photovoltaic power systems whole around the world has also been examined in this study. The cumulative global installed capacity is announced as around 137 GW in 2013 by EPIA. When it comes to the annual installed capacity, it can be seen an exponential effect in recent years. In present case Germany is still the first country in world in relation with the cumulative installed capacity. But it can be seen that especially China and USA will capture the level of Germany and will pass its level in upcoming years. The cumulative installed capacity of Turkey regarding photovoltaic power systems is very small when it is compared to those countries mentioned above.
The differences of photovoltaic power system applications between rooftop and field projects were also explained in the study.  Various examples of using and styles of the rooftop photovoltaic power system applications were examined as well. Current status of the Building Integrated Photovoltaic (BIPV) products were also researched.
Researchs and studies from around the world related to energy efficiency topic, energy efficiency in buildings specifically, low carbon sustainability, renewable energy and solar photovoltaic applications, decreasing carbon levels and emissions, regulation and targets published by different states and countries to improve energy efficiency and life standards etc. have been examined in this study, additionally.
Performance Ratio, which is very important parameter of a photovoltaic power system shows the relation between global irradition and the electricity production of a system, was calculated with the values obtained from the pyranometer which is established on site. The comparison between the simulation report which was created by a professional simulation program before installation of the photovoltaic power system and the real Performance Ratio of the system was carried out. While the Performance Ratio simulated before installation of the system was %82,4, the Performance Ratio with the recorded values by pyranometer calculated as %85,75. Furthermore with the values obtained from the pyranometer, the reliability of the simulation program related to the global irradiance value has been researched. Thanks to the comparison it is seen that the simulated irradiance levels by simulation program are lower than the irradiance values recorded by pyranometer. Additionally because of the irradiance levels are differs by versions of the simulation program, the differences of the irradiance values between updated version and previous versions of the program has been examined.
The compatibility of the photovoltaic modules and solar inverters used in photovoltaic power systems was examined in technical analysis of the photovoltaic power system. Polycrystalline cell technologies was chosen to use within the project and totally of 2024 solar modules each has 245 Wp power capacity have been installed. Regarding the solar inverter, string solar inverter technology was chosen to use and total of 22 inverters each has 20 kWe power capacity has been installed within the project. The equations and calculations which are necessary to design of photovoltaic power systems have been done.  The details related to connection of the system for instance as Single Line Diagrams and any other specifications have been presented additionally. In the total DC capacity of the system was designed as 495,88 kWp and AC capacity of the system was designed as 440 kWe.
The feasibility of this kind of projects is investigated by taking into account of initial cost of the project, total profits and gainings, production values and Performance Ratio (PR) of the system. Technical and cost analysis of the system have been carried out in addition as well. Considering all those  analyses, the potential benefits of photovoltaic power systems to reach the targets set by Turkey in respect of energy efficiency has been studied. Turkey's energy efficiency targets published in 2012 in a report named Energy Efficiency Strategy Document.
In the matter of cost analysis five different analysis methods which are Present Worth (PW), Future Worth (FW), Annual Worth (AW), Benefit/Cost Ratio (BCR) and Internal Rate of Return (IRR) have been used. As a result the photovoltaic power system analysed in this thesis was found as feasible in all of the cost analysis methods mentioned above. The payback period of the system was predicted lower than 10 years according to the calculations. While the initial cost of the system was 1.389.052,22 TL, total gaining of the system was calculated as 230.864,64 TL in 18 months. It is seen that the photovoltaic power system has paid %16,62 of its inital cost so far. Beyond the cost analysis methods mentioned above, some alternatives related to the project was evaluated. In current status while the building needs electricity and the photovoltaic power system produces the electricity, the produced electricity by photovoltaic power system uses for the consumption of the building. In alternative scenario, with an additional Medium-Voltage Transformator and Medium-Voltage Cells, the produced electricity by photovoltaic power system could be sold to the grid directly. Comparison between the current status and the alternative scenario, it is seen that the payback period of the system would be shorter in alternative scenario although the additional cost of Medium-Voltage Transformator and the Cells. While the Simple Payback Period –SPP- of current status was 8,83 years, it would be 7,55 years in alternative scenario.
Incentives and supports of different countries to increase using and installing of photovoltaic power systems have also been researched in this study. It can be seen that the incentives related to photovoltaic power systems in buildings are generally specified in many countries. The incentives differ by a country to another according to the capacity of the systems, application type or photovoltaic technology. While most of the incentives are feed-in tariff supports, there are also another type of incentives in many countries such as capital support, tax reduction and tax immunity etc. Considering those incentives of other countries, legislation of Turkey which named The Legislation Regarding to Unlicensed Electricity Production on Electricity Market has been compared. The legislation in Turkey provides a feed-in tariff value by 0,133 US$/kWh but there is no any other incentive beyond that feed-in tariff value. Furthermore the incentive for a photovoltaic power system has a capacity of 1 kWp or 1.000 kWp is equal and the procedures are the same, a suggestion offered to develop and extend the legislation. Another questionable feature of the legislation is that it is not clear what will be happened to produced energy by photovoltaic power system after 10 years. This time period is shorter than any other countries and here is a polemical side of the legislation. A legislation is extended and developed to increase and make easier of the applications and installing of photovoltaic power systems would be beneficial for Turkey to improve its energy efficiency and to decrease its energy intensity within the scope of its targets and strategies published in Energy Efficiency Strategy Document for upcoming years.