Spatial Assessment of Agro-photovoltaic (AgroPV) Suitability Using Geographic Information System in Coimbatore District, Tamil Nadu, India

Abstract

Agro-Photovoltaics (AgroPV) is a dual land-use strategy that enables simultaneous crop production and solar electricity generation on the same parcel of land, offering a practical response to the growing competition between food and energy security. This study presents a Geographic Information System (GIS)-based multi-criteria spatial suitability assessment for AgroPV development in Coimbatore District, Tamil Nadu, India. Five categories of thematic criteria were evaluated and overlaid, namely solar resource availability, land suitability and agricultural land cover, topographic and technical feasibility, infrastructure and grid accessibility, and environmental constraints. Slope was derived from the Shuttle Radar Topography Mission (SRTM) Digital Elevation Model, with areas having slopes of less than 8° considered feasible; solar potential was assessed using Global Horizontal Irradiance (GHI) data greater than 4.5 kWh/m²/day from the Global Solar Atlas; cropland extent was mapped using the ESRI Land Use/Land Cover (LULC) 2024 dataset; and infrastructural accessibility was evaluated using OpenStreetMap road, rail, and electrical substation layers with 10 km and 25 km proximity buffers, respectively. The reclassified thematic layers were standardised and overlaid, without differential weighting, in a GIS environment to generate a composite AgroPV suitability map. The analysis identified approximately 1364.55 sq. km (136,455 ha) of land, about 28.7% of the district's total geographical area of 4746.24 sq. km, as technically suitable for AgroPV implementation, with Sulur, Annur, and Mettupalayam taluks showing the largest suitable extents. The findings indicate that Coimbatore District possesses a substantial and spatially well-defined agricultural land base with favourable solar irradiance, gentle terrain, and strong grid and transport connectivity, making it a technically suitable candidate for large-scale AgroPV deployment, subject to further economic, agronomic, and field-level feasibility assessments. The study demonstrates a scalable, low-cost, first-order GIS-based screening methodology for identifying priority zones for integrated solar-agriculture development; it is intended to guide rather than substitute for detailed feasibility and field-level assessments and provides a decision-support basis for regional energy and land-use planning.