Why are overhead power lines a common sight?

Overhead power lines are common because they are cost-effective, easy to install, and require less land than underground lines.

Overhead power lines are a familiar sight in many parts of the world due to their cost-effectiveness. The cost of installing overhead power lines is significantly lower than that of underground lines. This is because overhead lines require fewer materials and less labour for installation. The cables used for overhead lines are also less expensive as they do not need the heavy insulation required for underground cables.

In addition to being cost-effective, overhead power lines are easier to install. They can be erected on poles along existing roads or across open land, without the need for extensive excavation work. This makes them a practical choice in both urban and rural areas. The installation process is also quicker, which means that power can be supplied more rapidly to areas in need.

Overhead power lines also require less land than underground lines. Underground cables need a wider path to allow for the necessary safety clearances and to provide access for maintenance and repair work. In contrast, overhead lines require only a narrow strip of land, with the poles typically spaced 50 to 200 metres apart. This makes them a more feasible option in densely populated areas or places with limited available land.

Furthermore, maintenance and repair work on overhead lines is generally easier and quicker to carry out than on underground cables. Faults can be visually identified and repaired without the need for excavation. This not only reduces the time taken to restore power following an outage, but also contributes to the overall lower cost of overhead lines.

However, overhead power lines do have some disadvantages. They are more vulnerable to damage from severe weather, birds, and falling trees. They can also be a visual blight and are often considered less aesthetically pleasing than underground lines. Despite these drawbacks, the benefits of overhead power lines in terms of cost, ease of installation, and land use make them a common sight in many parts of the world.