Regional Photovoltaic Siting in Shaanxi: Integrating Ecological Value and Electricity-Demand Accessibility

Regional photovoltaic screening must reconcile land availability with ecological and electricity-demand priorities. We compared eight photovoltaic siting scenarios in Shaanxi using province-wide or regional weights derived from criterion variability and correlations. Ecological components and siting criteria, including ERA5 solar irradiation, were weighted separately. The full regional model identified 13,428.59 km2 at suitability ≥0.60. Under the separate 2872.26 km2 Top10 selection budget, adding ecological compatibility to the demand-based scenario lowered mean ecological constraint index (ECI) by 0.0883. Adding demand accessibility to the ecology-based scenario increased mean electricity-demand accessibility index (EDAI) by 0.0125. However, adding ecology raised or lowered EDAI depending on aspect treatment and resolution. The resolution comparison used a separate budget within common allowed footprints. Retrospective area under the receiver operating characteristic curve (AUC) ranged from 0.6575 to 0.6736 across the two full models and a six-factor analytic hierarchy process benchmark for 145 eligible photovoltaic polygons; paired comparisons did not resolve relative performance. Proximity grouping retained 2426.44 km2 in 929 planning groups comprising 9398 distinct physical patches. These comparisons quantify how weighting, ecological and demand criteria, and spatial representation change the land prioritized for municipal assessment.