Integrating solar photovoltaics in river basins: advancing water–energy–climate synergies for sustainable development goals

ABSTRACT The graph describes the framework for USPV siting in river basins, including site suitability analysis, scenario design for USPV plant selection, and economic and ecological outcomes assessment. Utility-scale solar photovoltaic (USPV) deployment in river basins involves critical trade-offs among technological feasibility, economic performance, and ecological conservation. This study proposes an integrated decision-making framework for USPV siting in the upper Jinsha River by incorporating multiple criteria under different priorities. Results show that economic-priority scenarios allocate more than two-thirds of the suitable development areas east of the river, with median economic costs of 0.33–0.34 CNY/kWh and ecological costs of 0.013 CNY/kWh. Conservation-priority scenarios shift 60% of the suitable development areas westward, increasing economic costs to 0.36 CNY/kWh while reducing ecological costs to 0.006–0.007 CNY/kWh. Although total land conversion areas remain comparable across scenarios, differences in land conversion types result in carbon emissions of 1.04–1.13 Mt CO2 under economic priorities and 0.46–0.53 Mt CO2 under conservation priorities. These findings support spatially differentiated USPV planning that contributes to sustainable development goals (SDGs), particularly SDG 7 (Affordable and Clean Energy), SDG 13 (Climate Action), and SDG 15 (Life on Land), while strengthening water–energy–climate synergies in river basins.