Revealing the solar energy potential by integration of GIS and AHP in order to compare decisions of the land use on the environmental plans

Due to the depletion of fossil fuel resources, interest in renewable energy sources is steadily increasing in the world. Turkey, is very rich in terms of its solar energy potential enabling it to use the sun as a means of generating energy. Thanks to marginal lands such as non-residential areas, agricultural areas and industrial areas, electricity production is provided by means of renewable energy sources. Since land is a scarce resource, optimal use of it is a spatial necessity. In developed societies its usage is determined in the environmental plan based on criteria related to industry, agriculture etc. and presented to decision makers for their approval. However, in these plans, natural energy potentials such as the sun and wind can often be ignored. This lack of planning hinders the effective utilization of the solar energy potential. A case study has been carried out to better understand this issue. The most commonly used Solar Power Plant criteria have been determined with the literature review, an informal interview with SPP experts and the authors' experiences and these criteria have been weighted with the Analytical Hierarchy Process method. A cost-surface map has been produced for the study area and the environmental plan has been associated with it. It has been determined that areas that have a very high solar energy potential in the cost-surface map have been planned for urban, commercial or different purposes in the environmental plans. In spite of the fact that the solar energy potential atlas shows the same solar potential for the study area, there are still huge differences in terms of solar energy potential among some regions in the study area. For this reason, it is not logical to build SPP facilities based only on the solar energy potential atlas. It is suggested to determine natural energy potential spatially throughout the country and consider it before the environmental plans are prepared. In addition, those wanting to research this subject are recommended to conduct studies in areas promoting alternative methods according to alternative site selection criteria including geographical and soil characteristics.