Why is aluminum conductor often preferred in electrical applications?

Aluminum conductors are often preferred for electrical applications primarily due to their excellent strength-to-weight ratio and cost-effectiveness. In high-voltage transmission lines, the size of the conductor is critical because larger conductors can help to reduce corona loss, which occurs when electrical discharge happens to the surrounding air due to ionization. This phenomenon can lead to energy loss and potential damage to the transmission system.

The larger diameter of aluminum conductors effectively decreases the intensity of the electric field at the surface, lowering the likelihood of corona discharge. This results in more efficient electrical transmission, especially over longer distances. The reduced weight of aluminum, compared to copper, also makes it easier to handle and install, which benefits infrastructure development.

While the other aspects related to cost, conductivity, and flexibility also play roles in the consideration of material choice, the significant impact of conductor size on minimizing corona loss specifically highlights why aluminum is favored in high-voltage applications.