Abstract
Against the background of the “Dual Carbon” strategy, adopting energy-saving conductors is a vital measure to reduce transmission line losses and carbon emissions. In this paper, an AC resistance test platform is built to characterize the AC resistance and temperature-rise features of conventional ACSR and three energy-saving conductors. Typical main transmission lines and tie-lines in Chongqing are selected as engineering cases to compare their transmission capacity, line loss and CO2 emission reduction performance. The results demonstrate that JLHA3 has the lowest AC resistance and the greatest potential for loss and carbon reduction, yet its high incremental investment weakens its economic competitiveness under the adopted carbon price scenario. JL3/G1A strikes a good balance between incremental investment and energy-saving benefits, making it the economically favorable option for high-utilization main supply lines. For tie-lines with low annual utilization hours, only JL3/G1A remains economically viable among the three energy-saving conductors, although its economic margin is narrow; JLHA3 and JL3/LHA1 fail to recover their additional construction costs over the whole service life cycle. This study can support hierarchical conductor selection and the low-carbon retrofit of transmission lines.