Geographical Distribution and Potential of Solar Energy Resources in the Dungarpur and Banswara Districts of Southern Rajasthan, India: A GIS-Based Multi-Criteria Assessment

Abstract

Solar energy development in India has been geographically uneven, and the reasons for that unevenness remain poorly understood at the sub-district scale. This study therefore analyses the geographical distribution, technical potential and socio-economic implications of solar energy development in the Dungarpur and Banswara districts of southern Rajasthan, and derives region-specific policy recommendations. The study area covers 8,807 km² and comprises sixteen tehsil units. Two complementary data streams were combined. On the resource side, long-term satellite-derived global horizontal irradiance (GHI) was interpolated to map the solar resource; a composite Solar Potential Index (SPI) was then constructed for each tehsil unit from six indicators weighted by the Analytic Hierarchy Process (consistency ratio 0.06); land suitability for utility-scale photovoltaics was mapped by weighted-overlay multi-criteria decision analysis using irradiance (0.35), grid proximity (0.30), terrain (0.25) and exclusion layers (0.10); and technical potential was estimated separately for five deployment modes, supported by a monthly simulation of a 1 MW fixed-tilt plant. On the demand side, primary data were obtained from 400 respondents in twenty villages by multi-stage stratified random sampling and analysed using percentages, Pearson's correlation, chi-square and t-tests. The results show that annual mean GHI is 5.32 kWh/m²/day in Dungarpur and 5.18 kWh/m²/day in Banswara, declining from north-west to south-east, with a monsoon reduction of 38–40%; the optimum fixed tilt is approximately 20° facing south and a 1 MW plant would generate about 1,614 MWh annually, corresponding to a capacity utilisation factor of 18.4%. Across the sixteen units the SPI correlates most strongly with grid proximity (r = 0.90), road connectivity (r = 0.73) and level land (r = 0.70), but only moderately with irradiance (r = 0.49). Highly suitable land accounts for 10.9% of Dungarpur but only 1.2% of Banswara, and total technical potential is 8,340 MW against an installed capacity of about 135 MW, representing a utilisation rate of 1.6%. Among surveyed solar pump users, irrigated area rose 46%, cropping intensity 25% and net farm income 47%, while irrigation expenditure fell 86%. Taken together, these findings indicate that solar development in this hilly, densely populated tribal region is constrained primarily by terrain, land competition and grid infrastructure rather than by the availability of solar radiation. It follows that policy should move beyond the large solar-park model of western Rajasthan towards decentralised, water-linked and community-owned deployment.