Spatial assessment of site suitability for solar desalination plants: a case study of the coastal regions of Turkey

Many countries, especially in arid and semiarid regions, suffer from water scarcity because of the decline in the existing freshwater reserves by consumption and pollution. Climate change also makes the problem even more difficult and costly. In order to resolve the increased water scarcity problem, seawater desalination powered by renewables such as solar and/or wind can be an opportunity to reduce future concerns of countries related to increased water demand. Site assessment for solar desalination plants is also essential in planning the establishment of these facilities, and many factors including environmental, economic, demographic, and climatic criteria should be taken into account. The study aims to develop a geographic information systems–multi-criteria evaluation (GIS-MCE) model divided into three sub-models including (1) fuzzy factor standardization, (2) analytic hierarchy process-based factor weighting, and (3) aggregation of sub-models in a logical manner. This study focuses on a model where environmental, demographic, and climatic factors are evaluated, but economic requirements, energy requirements, and uncertainties of desalination are not addressed. The developed GIS-MCE model assessed the site suitability of coastal regions of Turkey under the consideration of six criteria such as seawater temperature, seawater salinity, solar radiation, precipitation, population, and water unit price. As a result of the study, the most suitable sites for solar desalination were identified as İstanbul, İzmir, and Aydın in the Marmara and the Aegean regions, while the cities Artvin, Trabzon, and Rize in the Black Sea region have the lowest suitability. Graphic abstract