The usage of stochastic and multicriteria decision-aid methods evaluating geothermal energy exploitation projects

Abstract

This study is based on three main questions about the utilization of geothermal energy. The first question is how much heat energy the geothermal resource contains? The second one is what the utilization alternatives are for this resource? And the last question is according to which criteria the scenarios formed by integration of the selected utilization alternatives in specified proportions could be assessed, and what the alternative schema obtained could be like? The method of forming a model by simulations, which is developed as an approach to the solutions of the problems that contain uncertain parameters, like what the heating capacities of the reservoirs are, is used in this study. A model is formed with parameters of the heating capacity of Balçova Geothermal Field by employing Monte Carlo Simulation Technique. Here the aim is to find the amount of the heating energy that could be exploited by sustainable way from the resource. Efforts are given to form the amount of this energy by the help of cumulative probability distribution of the model. It is emphasized what the estimated heating reserve and the alternatives that could be locally utilized. Here, parameters such as the enthalpy of the geothermal resource, content of the fluid, volume of the geothermal field, pattern of the settlement in the field, ability of the soil, topography and structure of the labor etc. should be considered in the light of reconnaissance and exploration studies done in the geothermal field. From the assessment done for Balçova, it is concluded that geothermal resource could be utilized for heating of the dwellings, greenhouse agriculture, thermal tourism and dehydration of fruit and vegetable. Having determined the utilization schema of the geothermal resource, the issue of the assessment of the scenarios, which will be formed from these alternatives, comes up. Here begins the decision making process with a political aspect. By determining the criteria that will be considered while selecting the scenarios, and by determining the relative weights of this criteria, an order which shows the desired situation between the scenarios could be obtained. In this study, the scenarios formed in Balçova are assessed by the help of PROMETHEE method .one of the Multicriteria Decision aid Technique. As a result, it is seen that in Balçova tourism related scenarios stand out because of their superiority in employment created and Tons of Petroleum Equivalent energy values.