Advantages:
1. As Transmission voltage increases, current decreases.
2. As current decreases, cross section of conductor decreases.
3. As cross section of conductor decreases, its weight decreases.
4. As weight of the conductor decreases, design of tower becomes lighter in weight.
5. As current decreases, cross section of bus bar and size of switch gear contact etc. reduces.
6. Due to above advantages, Transmission cost per KM decreases
7. As transmission voltage increases. A current decreases, so copper losses in transmission line reduces.
8. As copper losses reduces, transmission efficiency increases
9. As current reduces, voltage drop in transmission line reduces.
10. As voltage drop in transmission reduces, voltage regulation becomes better (improved).
11. As efficiency and regulation of transmission line gets improved, so performance of transmission line increases
12. As transmission voltage increases power handling capacity of transmission line increases
13. Due to high voltage transmission line, successful interconnection of transmission line is possible than low voltage.