Multi-criteria GIS-based modelling technique for identifying potential solar farm sites: A case study in Mauritius

Abstract Determining economically viable and highly efficient strategic locations for utility-scale solar power plants is a costly procedure that depends on several factors. This paper investigates the spatial suitability for installations of ground-mounted solar farms based on legal, social, technical, economic, environmental and cultural perspectives through the use of Geographic Information System (GIS) analysis combined with Multi-criteria Decision Making (MCDM) technique. A set of six exclusion criteria are identified and removed from the map layer considered exploitable for construction. The Analytical Hierarchy Process (AHP) is then used to determine the weights of nine selected evaluation criteria found to influence the placements of the farms. Proximity raster layers were derived from features including road network and high transmission lines, overlain with a 10 m × 10 m raster terrain layers which includes elevation, slope and aspect and finally combined with interpolated raster dataset of climatological parameters comprising of global solar radiation, sunshine duration, air temperature and relative humidity. This combinatorial process through the Weighted Linear Combination (WLC) technique generated a high resolution solar resource potential atlas classifying regions on the island from high to low potential for solar farm placement. Further analysis of highly suitable sites with aerial images of the localities of interest resulted in the identification of 3 best sites all situated in the northern plains of the island. The approach demonstrated is expected to help reduce time, money and resources presently allocated towards identifying and assessing hot spots for the construction of solar power plants in Mauritius.