Mountainous regions, such as the Alps, Appalachians, Andes, and Qingzang Plateau, offer vast renewable energy potential, but geographical and ecological challenges limit conventional overhead transmission lines. Underground alternatives, including gas-insulated lines and cables, provide viable solutions but require comprehensive techno-economic evaluation for sustainable deployment. This study integrates multi-physics analysis, combining electromagnetic, thermal, and fluid dynamics, with lifecycle cost assessment per unit transmission task to compare overhead and underground tunnel transmission systems. Optimized conductor designs and ventilation strategies enhance cable capacity and improve economic performance, particularly in regions with high external costs. Here, we show that underground tunnel based power transmission systems, especially gas-insulated lines, deliver cost-effective, high-capacity transmission solutions for mountainous renewable energy concentrated regions, outperform overhead power transmission infrastructure when external costs, including ecological, landscape, and infrastructure constraints, are significant, thus advancing the goals of sustainable renewable energy integration and net-zero. The study evaluates underground tunnel transmission for renewable energy in mountains, using multi-physics analysis and lifecycle cost evaluation. It finds gas-insulated lines are cost-effective in areas with high environmental impact costs, optimizing conductor layout and ventilation for increased capacity.
Fan et al. (Thu,) studied this question.