Assessing photovoltaic development potential and synergistic benefits in railway-adjacent spaces of high-altitude regions: A case study of the Qinghai-Tibet Plateau

With China’s ambition to reach the goal of carbon peak and carbon neutrality, railways face growing pressure to reduce carbon emission and improve energy efficiency due to its high electricity consumption. Meanwhile, in Qinghai–Tibet Plateau, a key PV base, the uncoordinated development and inefficient land use have caused some problems. This study establishes a comprehensive suitability evaluation framework for PV deployment in cold and high-altitude regions, identifies priority areas along the Qinghai–Tibet Railway, and evaluates electricity demand, generation potential, and integrated benefits across multiple development phases and power supply scenarios，which may provide some references for PV development in this region. The results show: (1) significant spatial variation in development suitability, with priority zones mainly in Seni and Golmud; (2) substantial PV potential—developing just 0.5 % of the most suitable area in the Xining–Golmud section could meet the electricity need of this section, while developing 2 % would fully cover the demand of the whole railway line; (3) Great benefits in both PV electricity generation and carbon emission. It has been found that Scenarios 1–3 (without storage system) achieve lower LCOE and slightly higher carbon reduction than Scenario 4 (with storage system). ROI increases under carbon trading in all scenarios, notably with greater gains in Scenarios 1–3. Although Scenario 4 yields lower short-term economic returns, considering its strategic value for improving supply reliability, especially for nighttime operations and in extreme climates. Therefore, this it is strongly recommended that the integrated “generation–consumption–storage–trading” power supply system should be adopted to promote local renewable energy use, reduce reliance on conventional grids, and improve the sustainability of railway electrification in high-altitude regions. • A demand-oriented evaluation system for railway PV development is proposed. • Integrated benefits include power output and monetized emission reductions. • Comparative analysis is conducted across scenarios and development stages along railways. • A “Generation–Consumption–Storage–Trading” power system is introduced for cold, high-altitude rail regions.