How does a transformer improve efficiency in the National Grid?

A transformer improves efficiency in the National Grid by reducing energy losses during electricity transmission over long distances.

In the National Grid, electricity needs to be transmitted over long distances from power stations to homes and businesses. When electricity travels through wires, some of it is lost as heat due to the resistance of the wires. This is where transformers come in handy. They work by changing the voltage of the electricity. At power stations, step-up transformers increase the voltage to very high levels, sometimes up to 400,000 volts. This high voltage means that the current is lower for the same amount of power, and since energy loss due to resistance is proportional to the square of the current, reducing the current significantly cuts down on these losses.

Once the high-voltage electricity reaches its destination, it needs to be made safe for use in homes and businesses. This is done using step-down transformers, which reduce the voltage to safer levels, typically 230 volts in the UK. By using transformers to step up the voltage for transmission and then step it down for usage, the National Grid can transport electricity more efficiently and with less energy wasted as heat.

Transformers are crucial for maintaining the balance between efficiency and safety in the National Grid. Without them, we would need much thicker and more expensive wires to carry the same amount of power, or we would lose a lot more energy as heat, making the whole system less efficient and more costly. So, transformers play a key role in ensuring that electricity is delivered efficiently and reliably to where it is needed.