<p>The negative environmental impacts of reliance on fossil fuels underscore the urgent need to shift to renewable energy, especially solar power. Therefore, region-specific suitable site planning is essential for developing solar infrastructure and advancing decentralized energy access. This study assessed site suitability for solar photovoltaic (PV) placement in the Birbhum district using the Fuzzy Analytic Hierarchy Process (FAHP), the Method Based on the Removal Effects of Criteria (MEREC), and the Multi-Objective Optimization on the basis of a Ratio Analysis plus the Full Multiplicative Form (MULTIMOORA) techniques. The significance of this present research is underscored by the use of both a subjective and an objective multi-criteria decision making (MCDM) model. Further, integrating the novel MEREC-MULTIMOORA technique with GIS for the first time, which has not been previously reported in the literature. FAHP-based site suitability model findings showed 811.41 km² as highly suitable for solar PV plant development, while MEREC indicated 623.37 km² as highly suitable. Rajnagar, Khoyrasol, and Dubrajpur ranked highly in the FAHP and MEREC-based Multimoora models, suggesting they should be prioritized for initial solar PV development. Single-parameter, along with map-removal, sensitivity analysis results indicated that the models were reliable, with no criterion dominating the final suitability model. The Receiver Operating Characteristic – Area Under the Curve (ROC-AUC) analysis indicated that the FAHP-based model reached an AUC of 0.896, surpassing the MEREC-based model’s value of 0.869. The findings offer important insights for planners and policymakers regarding sustainable, phased solar planning in the region.</p>