The Power Transmission Losses: Kajaki to Kandahar Breshna Kot

In this comprehensive study, we investigated the significant voltage drop observed in the 110 kV high-voltage transmission line connecting the Kajaki Hydroelectric Power Plant to the Kandahar Brishna Kot substation, spanning 171 km. The drop is mainly due to the line’s extended length and its resistive and reactive characteristics. Using both quantitative and qualitative methods, supported by ETAP software and data from Da Afghanistan Breshna Sherkat (DABS), the analysis revealed that the voltage drop exceeds the International Electrotechnical Commission (IEC) standards, resulting in significant power losses. To mitigate this issue, the study recommends upgrading the voltage level from 110 kV to 220 kV. This enhancement would reduce current, minimize resistive losses, and improve efficiency by increasing the conductor's cross-sectional area and reorganizing the transmission route with standard components. Implementing these measures is projected to significantly decrease power losses and enhance the overall reliability and performance of the regional power transmission system.