مکانیابی مناطق دارای پتانسیل زمین گرمایی به کمک روش های تصمیم گیری چندمعیاره

تعیین مناطق دارای پتانسیل انرژی زمین گرمایی جهت اکتشاف و بهره‌برداری انرژی‌های پاک و سازگار با محیط زیست، دارای اهمیت ویژه است. هدف از این مطالعه کاوش مناطق دارای پتانسیل زمین گرمایی با توجه به ویژگی‌های زمین شناسی مناطق شمال غربی کشور، با استفاده از سیستم های اطلاعات مکانی  و روش‌های تصمیم‌گیری چندمعیاره می‌باشد. در این مطالعه از بسته تحلیل چند معیاره مکانی  نرم افزار ilwis و همچنین روش تصمیم‌گیری مبتنی بر وزن‌های ترتیبی  در نرم افزار terrset استفاده شده است. پنج استان شمال غربی ایران شامل آذربایجان غربی و شرقی، اردبیل، کردستان و زنجان، که دارای تعداد زیاد چشمه‌ی آب گرم بوده و از لحاظ زمین گرمایی از اهمیت بالایی برخوردارند به عنوان منطقه‌ی مورد مطالعه انتخاب گردید. از میان چشمه‌های آب گرم منطقه، تعداد 9 چشمه در مرحله پتانسیل سنجی و 30 چشمه نیز به منظور ارزیابی نتایج حاصل از سناریوهای مختلف تصمیم‌گیری، به کار گرفته شدند. به منظور اعتبار سنجی نتایج مدل‌سازی‌های صورت گرفته، 8 سناریوی مختلف تصمیم‌گیری حاصل از ترکیب معیارهای مورد ارزیابی، مشخص گردید و نقشه تناسب زمین گرمایی حاصل از مدل‌سازی سناریوها با موقعیت چشمه‌های آب گرم موجود مقایسه و مورد ارزیابی قرار گرفت. در این راستا با توجه به محل چشمه‌های آب گرم موجود که نشان از وجود پتانسیل زمین گرمایی هستند، تعداد این چشمه‌ها در هر کلاس تناسب برای سناریوهای مختلف مشخص شد. نتایج حاصل از سناریوهای مختلف و همپوشانی با چشمه‌های آب گرم در منطقه که نشانگر وجود منابع زمین گرمایی هستند، نشان دهنده سازگاری نتایج مطالعه با واقعیت زمینی است. در اغلب سناریوها، چشمه‌های آب گرم در کلاس‌های متناسب یا خیلی متناسب قرار گرفته‌اند. این بدان معناست که نتایج حاصل از این مطالعه قابل قبول بوده و می‌تواند در برنامه‌ریزی‌های مربوطه مورد استفاده قرار گیرد.

Locating areas with geothermal potentialusing multicriteria decisionmaking methods

IntroductionThe study of the areas with geothermal energy potential is of particular importance in realizing the goals ofsustainable development. Areas with geothermal potential areof great importance in terms of application as renewable energy resources, tourist attraction, greenhouse construction, etc.Generally, in geothermal exploration projects, studies are initially carried out with regard to the existing indicators, and the outcome of the primary location is used for more detailed studies. The identification of the areas with geothermal potential, which is the first phase of geothermal energy exploration, is complex and difficult.Determining areas with geothermal energypotential as a basis for clean and environment friendly natural energyexploration studies, is important for achieving sustainable development. The purpose of this paper is to identify the areas with geothermal potential with regard to the characteristics of the northwest regions of Iran and the application of Geospatial Information Systems and Multicriteria analysis methods, which have many advantages in the field of exploring the regions with geothermal potential.In this study, the spatial Multicriteria analysis package of ILWIS software and also the decisionmaking method based on the Ordered Weighted Average (OWA) in TerrSet(IDRISI) software have been usedDifferent scenarios of decisionmaking were implemented in the case study area and, the results were compared with the location of hot water springs in the region. The results indicate that the location of the determined sites is close to the hot water springs, which confirms the results of the proposed model of the paper. Materials & MethodsThe study of geothermal energy with the help of the spatial information system has drawn the attention in recent years. The purpose of this paper is to study areas with geothermal potential in the northwestern regions of Iran. These regions have different effects on the Earthand the researchers of this field use these effects to find new methods for measuring geothermal resources (Yousefy, 2006). Nowadays, GISbased MCDM techniques are effectively used in these types of studies. Therefore, it has been tried to use some of these techniques in this research. In addition to the novelty of the topic of the geothermal studies in Iran, the issue of modeling different decisionmaking scenarios has been taken into consideration fromthe pessimistic view (with low risk) to the optimistic one (with high risk). Therefore, in this research,areas with geothermal potential have been identified and compared, with the help of study with the help of spatial data and Multicriteria decisionmaking methods. In this study, decisionmaking criteria are evaluated and selected usinglibrary studies from previous researches. Also, based on the weighting methods and the integration of criteria, 8 scenarios were produced and their results were compared with each other. Meanwhile, the weight of the criteria was calculated using questionnaires and the analytic hierarchy process (AHP) method. The Ordered Weighted Average (OWA) method was applied to create various scenarios. Figure1 shows the stages of this research. Results & DiscussionThe two software (ILWIS and TerrSet), provide powerful tool for standardizing, weighting and integratingthe standard maps associated with the decisionmaking process. In the implementation stage, the maps are standardizedafter the preparation of thestandard maps in the acceptable format of each software. In this study, fuzzy and AHP methods were used for standardization and weighting,respectively. Finally, the input factors are integrated according to different scenarios. The results are shown in Fig8. In order to evaluate the results, the geothermal map produced based on the model proposed in this article has been compared with the location of hot water springs. The results of most scenarios show that, hot water springs are generally located in two classes with high suitability which confirms the results of the research. In Fig9, hot springs are located in the classes with high suitability, as it was expected. This means that the results of this research are acceptable. Adaptation and compatibility of the geothermal map and the existing situation provide the possibility of using the results of the case study area in the exploration studies of other regions. ConclusionIn this research, multicriteria decisionmaking based on the use of GIS tool was used as a feasibility study in the first phase of geothermal exploration. The layers were processed and using theAHPOWA integration methods in the 8 scenarios, they were integrated and the obtained results were investigated and compared. In most scenarios, hot water springs are in suitable or very suitable classes. This reflects the acceptable results obtained from the proposed modeling of this research.