Spatial Suitability Assessment for Solar Photovoltaic (PV) Power Plant Siting in Al-Ula Governorate Using (GIS and AHP)

This study evaluates the spatial suitability for utility-scale solar photovoltaic (PV) power plants in Al-Ula Governorate, located north of the Madinah Region. To achieve this objective, a Multi-Criteria Decision-Analysis (MCDA) framework integrated with the Analytic Hierarchy Process (AHP) within a Geographic Information System (GIS) environment was implemented. Based on a comprehensive literature review, six main criteria domains were defined—climatic, technical, topographic, economic, social, and environmental—encompassing 22 sub-variables. Relevant spatial datasets were acquired and processed to generate primary thematic layers. Each layer was subsequently reclassified into three suitability classes and assigned standardized scores ranging from 1 to 3 according to their compatibility with solar energy infrastructure, where the most suitable class received the highest score and the least suitable received the lowest. Using the AHP calculator, the relative weights of the sub-variables and their corresponding main criteria domains were derived. Technical factors prioritized highest at 31.1%, followed by climatic (24.1%), environmental (17.0%), social (14.1%), economic (7.4%), and topographic factors (5.6%). These derived weights were integrated to model variable suitability across all domains, culminating in a robust spatial suitability model for solar PV deployment across the governorate. The final Weighted Sum Overlay modeling revealed suitability scores ranging from 36.1% in low-suitability zones to 94.3% in highly suitable regions, with a governorate-wide spatial mean of 65.8%. High spatial suitability zones are predominantly concentrated in the northern, northeastern, central, and northwestern sectors of the governorate, where most evaluation criteria align optimally. Zones exceeding an 80% suitability threshold span 1,451.72 km², representing 7.32% of the total study area.