Spatial Suitability Assessment of Photovoltaic Development in Shangyi County, Hebei Province, China

To coordinate renewable energy expansion with land use, grassland ecology, and agro-pastoral activities, this study developed a county-scale photovoltaic suitability framework for Shangyi County, Hebei Province, China, integrating a geographic information system (GIS) and the fuzzy best–worst method (FBWM). Spatial constraints were separated from nine suitability criteria, whose weights were derived from five experts. The results were examined using existing photovoltaic patches, repeated random backgrounds, criterion-weight perturbations, constraint-parameter scenarios, and candidate-screening thresholds. Constraint zones and potential development areas accounted for 44.15% and 55.85% of the county, respectively. High- and very-high-suitability areas covered 554.7546 km2, or 37.92% of the evaluated area, and were concentrated mainly in the north. Existing photovoltaic patches showed moderate spatial discrimination from random backgrounds (mean ROC-AUC = 0.6604; 95% empirical interval: 0.5394–0.7778), although 25.80% of their area overlapped the constraint mask. The main advantageous areas remained spatially stable under the tested constraint parameters. Six regional priority candidate regions covered 45.7718 km2 and were dominated by grassland, highlighting trade-offs between energy development, ecological protection, and agro-pastoral uses. Transparent spatial screening and robustness tests provide evidence for sustainable county-scale land and energy planning, while project decisions require further assessment of grid capacity, land tenure, ecological conditions, and stakeholder acceptance.