Multi-criteria decision-making for selecting a solar farm location to supply energy to reverse osmosis devices and produce freshwater using GIS in Iran

Abstract

Iran has 985,798 square kilometers of desert areas, equivalent to 59.8 percent of the country's total area. This factor causes the creation of salt marshes and, accordingly, the salinization of surface and groundwater. For the first time in this paper, an indirect method is presented to identify areas of Brackish water sources with 3000–10000 mg/L TDS in the entire country of Iran and simultaneously identify the area's potential in terms of the solar energy to provide energy for desalination by reverse osmosis devices. Other types of sources of water, such as seawater, which has more salinity than Brackish water (about 35000 mg/liter) are not investigated in this research, because the primary purpose of this article is to use water that exists in the form of ponds, wells, or surface water that water cannot be used for residential or agricultural purposes, at the same time, this water is not seawater. Simultaneously 16 data layers that include economic, environmental, technical, and geological parameters have been considered.The proposed methodology provides a structured decision aid, which can be used in other countries to identify the mentioned areas and produce fresh water using reverse osmosis devices. Geographic Information Systems (GIS) are used to generate layers of data and to apply the elimination criteria and constraints. Multiple Criteria Decision Analysis (MCDA) is then used to rank and sort the grids via the identified evaluation criteria. This research can also have two other applications. The first is for professionals who want to identify areas with saline water potential, and the second is for organizations that want to launch reverse osmosis desalination plants that work with solar renewable energy. Technically, there are about 160 cities in Iran that have an area of about 144440685120.498077 square meters, have saline water sources, and simultaneously have the potential to use solar energy as one of the renewable energy sources to power reverse osmosis desalination devices. Most of these areas are located in the east of Iran and these areas have high water stress. In this research, the city of Khansar with an area of 95917147.16 square meters, which is located in the province of Isfahan and in the central part of Iran, has surface and underground saline water resources that both technically and operationally, has the highest potential.