Correct Answer - Option 4 : Decreases cost of transformers, switchgear and other terminal apparatus
Advantages of high transmission voltage:
1. Reduces the volume of conductor material
The volume of conductor material required is inversely proportional to the square of transmission voltage and power factor. The greater the transmission voltage, the lesser is the conductor material required. Hence, the transmission at high voltages is economical.
2. Increases transmission efficiency
Transmission efficiency increases when the line voltage is increased.
3. Decreases percentage line drop
Percentage line drop decreases when the transmission voltage increases.
Limitations of high transmission voltage:
1. The increased cost of insulating the conductors
2. The increased cost of transformers, switchgear and other terminal apparatus.
