Use of geothermal energy at the house heating: an environmental and socio economic evaluation

Jared Diamond who is the owner of the Pultizer award asked "Why did not the inhabitants of the American continent invade the Eurasian continent, but the inhabitants of the Eurasian continent invaded the American continent"? In his book "Guns, Germs And Steel" which sold more than million copies. Among the answers to this question; the exploration of the use of fossil energy by the invading side (those living in Eurasia), the industrial revolution and the acceleration created by the successive series of industrialization can be added. Since all these events took place in the chronology of history, many technological developments were experienced and many innovations took place up to our date. However, in the context of industrialization, we have not changed our extraction techniques of fossil fuels which have accelerated our growth, nor have we have searched for alternative sources other than fossil fuels. Until the realisation of "global warming", which scientists have put forward in the last decades and which is mostly caused by the consumption of fossil fuels, the consumption of fossil fuels has begun to be taken seriously by everyone. It is an interesting irony from this point that solution was the renewable energy which was used by the people who were called "primitive" in the invasion of America. They were using such sources as much as the technology of that time allowed them. Many countries are now trying to reduce their dependence on fossil fuels with renewable energy sources in their countries. This study examines how renewable energy sources stand in ecology and economics dilemma and makes an assessment of different areas of their use. With this in mind, this study consults the concepts of deep ecology and urban sustainability. The usage patterns of geothermal energy, which is a potential renewable energy source in Turkey, in settlements, have been evaluated in terms of its economic and environmental potential. The conceptual framework of research has been established with these questions: "How does renewable energy differ from other energy types in terms of environmental and economic aspects? Geothermal energy can be used as a source of energy in the heating of residential areas, yet how does it differ from other types of renewable energy in this respect?; Which parameters depend on the use of geothermal energy in residential heating in urban areas?; How does the transition to geothermal energy contribute to economy and environment when a settlement is heated initially by fossil fuels? As a method, a comparative and quantitative research approach supported by the literature has been used. In this sense, the parameters for the heating of the residential areas were determined from the upper scale data-based evaluations obtained from the literature. Economical evaluation and comparison of these parameters obtained from the literature were made in the framework located in residential areas of geothermal resources in Turkey. In this master thesis study, it is aimed to make an environmental and socio economic evaluation of the use of geothermal energy in residential heating. Since geothermal energy is one of the renewable energy types in this respect, it primarily deals with the renewable energy types and factors that stand out against fossil fuels. At this point, factors such as climate change, reaching a peak period in the extraction of oil reserves and rising oil and fossil fuel prices have led the world to use renewable energy. The types of renewable energy determined to play a key role in addressing these drawbacks have been examined in terms of their use patterns, working prescriptions, advantages and disadvantages. Then, it was determined that fossil fuel types considered to be substitutes in the future were mostly used in the field of residential heating in urban areas as a result of the literature survey. For that reason, the suitability of all types of renewable energy for residential heating has been evaluated by a SWOT analysis taking into account the advantages and disadvantages. During this evaluation, findings were also obtained in terms of planning. At this point, it has been seen that wind, solar and water energy types are more prone to generating electricity than residential heating. In terms of spatial planning it is a disadvantage that these types of energy need a separate area and that environmental damage occurs when this area is being constructed. In the context of another research question of the study, geothermal energy has come forward in the field of residential heating. Geothermal energy sources, which are the result of tectonic activity in the Earth's seismically active region, have been found to provide positive results in residential heating when combined with combined heat and heat pump technologies that improve the energy efficiency of thermodynamic laws. When considered from the planning point of view, geothermal energy source which does not need to open separate areas like other types of renewable energy can be found in the vicinity of the settlement as well as below the settlement. It is considered to be very convenient because there will not be cost of welding transportation in the settlement. Since most of the geothermal installations are built underground, there will not be too much damage in the area. In addition, energy resources can be transported by using suitable transportation systems for remote resources, and the cost of transportation system can be saved by providing an improvement in the direction of urban resources and cheaper energy prices can be provided in connection therewith. After determining the suitability of geothermal energy for residential heating to be continuous, clean and cheap, the question of which parameters are related to this renewable energy type in residential heating has been researched. 19 settlements in Turkey in this direction using geothermal energy for residential heating was examined. Of these settlements, 9 were selected as an example for the study. This selection was made by looking at both the rate of healthy information acquisition and the fact that the parameters are points that can draw attention to the correlation study in the progressive section. The parameters are determined as the depth of the well related to the source, the cost of opening the well, the temperature of the well and the facial measurement related to the settlement or space as the heating capacity, the population, the number of houses heated with geothermal, and the winter season average temperature. Finally some questions have been directed to the experts of the subject evaluating environmental and economic changes in residential uses of geothermal energy for heating houses in Turkey. The quantitative data and the expert evaluations are evaluated together in the conclusion section in order to present environmental and economic implications of geothermal energy, as one of the renewable energy types used in residential heating. To evaluate the 9 selected settlements in terms of spatial planning; it is seen as a common feature that there is a frequent urban macro form concentrating in the center when looking at the places (Simav, Sandıklı, Kozaklı) that provide housing heating with high percentages. The energy source reaching the settlement on this side can be delivered to the dwelling without overspreading. The presence of many sources around the settlement also suggests that in the future, if the regions are developed, they can provide more heat to the houses. On the other hand, it is seen that the settlements that provide housing heating in very low percentages have an urban macro form, which is spread over a very wide area but is frequently structured such as Bergama and Sorgun. Low source heating capacities (3 MWt and 19 MWt) account for low percent residential heating. For Diadin, it is observed that a large urban macro form is scattered in a large area and a very low temperature average provides a low percentage of housing heating due to the reasons just before, even if the heating capacity of the source is above a certain level. In Edremit and Gönen, it is seen that urban morphology is quite dense and frequent in terms of planning. Having a high population eliminates the advantage of being close to the geothermal source. Although there are many geothermal resources around the settlement, their heating capacities are low. Kızılcahamam has a more dispersed city morphology than the other two settlements. If there is urban improvement towards other geothermal resources in the vicinity, more households can benefit from geothermal residential heating. This research aims to reveal the factors of the environmental and economical aspects of geothermal systems which are emerging in the field of residential heating as a result of global environmental and economic concerns. Spatial planning and other related disciplines will enable us to use geothermal energy in residential heating for the purposes of more efficient and correct usage.