Dual electrification

Dual electrification is when a train or a railway system can use two different types of power to move. Just like how you can use two different batteries to power your toy car, trains can use two types of power to move forward.

The two types of power that are used for dual electrification are usually overhead wires and a third rail. Overhead wires are supported by poles, and a pantograph on top of the train connects to these wires. The third rail is a metal bar that runs alongside the tracks, and a shoe on the bottom of the train collects power from this rail.

Imagine you have a toy car that can both run on batteries and be plugged into a wall outlet with a cord. This toy car can switch between batteries or the wall outlet, depending on what's available. Similarly, a train that uses dual electrification can use either overhead wires or the third rail, depending on what is available on a particular section of the track.

Using two different types of power can be really useful because it allows trains to travel farther without needing to stop and refuel. It also allows train companies to use either type of power based on what's most cost-effective or environmentally friendly for their trains.